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  • Question 1 - What type of dysarthria is typically caused by damage to the lower motor...

    Correct

    • What type of dysarthria is typically caused by damage to the lower motor neurons related to a tumor?

      Your Answer: Flaccid dysarthria

      Explanation:

      Dysarthria is a speech disorder that affects the volume, rate, tone, of quality of spoken language. There are different types of dysarthria, each with its own set of features, associated conditions, and localisation. The types of dysarthria include spastic, flaccid, hypokinetic, hyperkinetic, and ataxic.

      Spastic dysarthria is characterised by explosive and forceful speech at a slow rate and is associated with conditions such as pseudobulbar palsy and spastic hemiplegia.

      Flaccid dysarthria, on the other hand, is characterised by a breathy, nasal voice and imprecise consonants and is associated with conditions such as myasthenia gravis.

      Hypokinetic dysarthria is characterised by slow, quiet speech with a tremor and is associated with conditions such as Parkinson’s disease.

      Hyperkinetic dysarthria is characterised by a variable rate, inappropriate stoppages, and a strained quality and is associated with conditions such as Huntington’s disease, Sydenham’s chorea, and tardive dyskinesia.

      Finally, ataxic dysarthria is characterised by rapid, monopitched, and slurred speech and is associated with conditions such as Friedreich’s ataxia and alcohol abuse. The localisation of each type of dysarthria varies, with spastic and flaccid dysarthria affecting the upper and lower motor neurons, respectively, and hypokinetic, hyperkinetic, and ataxic dysarthria affecting the extrapyramidal and cerebellar regions of the brain.

    • This question is part of the following fields:

      • Neurosciences
      19.3
      Seconds
  • Question 2 - In which region of the CNS do serotonergic neurons have the highest concentration...

    Correct

    • In which region of the CNS do serotonergic neurons have the highest concentration of cell bodies?

      Your Answer: Raphe nuclei

      Explanation:

      The raphe nuclei in the brainstem are the primary location of serotonergic neuronal cell bodies in the central nervous system (CNS), which project to the brain and spinal cord. Noradrenaline is synthesised by the locus coeruleus, located in the pons. Dopamine is produced in the substantia nigra and ventral tegmental area in the midbrain. While the majority of serotonin is found in enterochromaffin cells in the gastrointestinal (GI) tract, this is not considered part of the CNS. These neurotransmitters play important roles in various physiological and psychological processes.

    • This question is part of the following fields:

      • Neurosciences
      12
      Seconds
  • Question 3 - Which hypothalamic nucleus plays the most significant role in establishing the set point...

    Correct

    • Which hypothalamic nucleus plays the most significant role in establishing the set point for daily circadian rhythms?

      Your Answer: Suprachiasmatic

      Explanation:

      Functions of the Hypothalamus

      The hypothalamus is a vital part of the brain that plays a crucial role in regulating various bodily functions. It receives and integrates sensory information about the internal environment and directs actions to control internal homeostasis. The hypothalamus contains several nuclei and fiber tracts, each with specific functions.

      The suprachiasmatic nucleus (SCN) is responsible for regulating circadian rhythms. Neurons in the SCN have an intrinsic rhythm of discharge activity and receive input from the retina. The SCN is considered the body’s master clock, but it has multiple connections with other hypothalamic nuclei.

      Body temperature control is mainly under the control of the preoptic, anterior, and posterior nuclei, which have temperature-sensitive neurons. As the temperature goes above 37ºC, warm-sensitive neurons are activated, triggering parasympathetic activity to promote heat loss. As the temperature goes below 37ºC, cold-sensitive neurons are activated, triggering sympathetic activity to promote conservation of heat.

      The hypothalamus also plays a role in regulating prolactin secretion. Dopamine is tonically secreted by dopaminergic neurons that project from the arcuate nucleus of the hypothalamus into the anterior pituitary gland via the tuberoinfundibular pathway. The dopamine that is released acts on lactotrophic cells through D2-receptors, inhibiting prolactin synthesis. In the absence of pregnancy of lactation, prolactin is constitutively inhibited by dopamine. Dopamine antagonists result in hyperprolactinemia, while dopamine agonists inhibit prolactin secretion.

      In summary, the hypothalamus is a complex structure that regulates various bodily functions, including circadian rhythms, body temperature, and prolactin secretion. Dysfunction of the hypothalamus can lead to various disorders, such as sleep-rhythm disorder, diabetes insipidus, hyperprolactinemia, and obesity.

    • This question is part of the following fields:

      • Neurosciences
      8.2
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  • Question 4 - Which condition is most commonly associated with Klüver-Bucy syndrome? ...

    Correct

    • Which condition is most commonly associated with Klüver-Bucy syndrome?

      Your Answer: Alzheimer's disease

      Explanation:

      Kluver-Bucy Syndrome: Causes and Symptoms

      Kluver-Bucy syndrome is a neurological disorder that results from bilateral medial temporal lobe dysfunction, particularly in the amygdala. This condition is characterized by a range of symptoms, including hyperorality (a tendency to explore objects with the mouth), hypersexuality, docility, visual agnosia, and dietary changes.

      The most common causes of Kluver-Bucy syndrome include herpes, late-stage Alzheimer’s disease, frontotemporal dementia, trauma, and bilateral temporal lobe infarction. In some cases, the condition may be reversible with treatment, but in others, it may be permanent and require ongoing management. If you of someone you know is experiencing symptoms of Kluver-Bucy syndrome, it is important to seek medical attention promptly to determine the underlying cause and develop an appropriate treatment plan.

    • This question is part of the following fields:

      • Neurosciences
      24.7
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  • Question 5 - What can be said about alterations in dopamine transporter levels observed in individuals...

    Incorrect

    • What can be said about alterations in dopamine transporter levels observed in individuals with ADHD?

      Your Answer: No different from healthy controls

      Correct Answer: Elevated due to psychostimulant treatment

      Explanation:

      The density of striatal dopamine transporters in individuals with ADHD is influenced by their prior exposure to psychostimulants. ADHD is a complex disorder that involves dysfunction in multiple neurotransmitter systems, including dopamine, adrenergic, cholinergic, and serotonergic systems. Dopamine systems have received significant attention due to their role in regulating psychomotor activity, motivation, inhibition, and attention. Psychostimulants increase dopamine availability by blocking striatal dopamine transporters. Individuals with untreated ADHD have lower levels of dopamine transporters, while those who have received psychostimulants have higher levels.

    • This question is part of the following fields:

      • Neurosciences
      53.3
      Seconds
  • Question 6 - Mirror neurons provide a biological framework for comprehending what concept? ...

    Correct

    • Mirror neurons provide a biological framework for comprehending what concept?

      Your Answer: Imitation learning

      Explanation:

      Mirror Neurons: A Model for Imitation Learning

      Mirror neurons are a unique type of visuomotor neurons that were first identified in the premotor cortex of monkeys in area F5. These neurons fire not only when the monkey performs a specific action but also when it observes another individual, whether it is a monkey of a human, performing a similar action. This discovery has led to the development of a model for understanding imitation learning.

      Mirror neurons offer a fascinating insight into how humans and animals learn by imitation. They provide a neural mechanism that allows individuals to understand the actions of others and to replicate those actions themselves. This process is essential for social learning, as it enables individuals to learn from others and to adapt to their environment.

      The discovery of mirror neurons has also led to new research in the field of neuroscience, as scientists seek to understand how these neurons work and how they can be used to improve our understanding of human behavior. As we continue to learn more about mirror neurons, we may be able to develop new therapies for individuals with social and communication disorders, such as autism.

      Overall, mirror neurons are a fascinating area of research that has the potential to revolutionize our understanding of human behavior and learning. By studying these neurons, we may be able to unlock new insights into how we learn, communicate, and interact with others.

    • This question is part of the following fields:

      • Neurosciences
      5.3
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  • Question 7 - Which of the following is not an example of glial cells? ...

    Correct

    • Which of the following is not an example of glial cells?

      Your Answer: Purkinje cells

      Explanation:

      The initial exam question erroneously included neurons as a potential answer instead of Purkinje cells. However, this was deemed too simplistic and was subsequently revised. It is important to note that glial cells serve as support cells for neurons, whereas Purkinje cells are a specific type of neuron and therefore cannot be classified as glial cells.

      Glial Cells: The Support System of the Central Nervous System

      The central nervous system is composed of two basic cell types: neurons and glial cells. Glial cells, also known as support cells, play a crucial role in maintaining the health and function of neurons. There are several types of glial cells, including macroglia (astrocytes and oligodendrocytes), ependymal cells, and microglia.

      Astrocytes are the most abundant type of glial cell and have numerous functions, such as providing structural support, repairing nervous tissue, nourishing neurons, contributing to the blood-brain barrier, and regulating neurotransmission and blood flow. There are two main types of astrocytes: protoplasmic and fibrous.

      Oligodendrocytes are responsible for the formation of myelin sheaths, which insulate and protect axons, allowing for faster and more efficient transmission of nerve impulses.

      Ependymal cells line the ventricular system and are involved in the circulation of cerebrospinal fluid (CSF) and fluid homeostasis in the brain. Specialized ependymal cells called choroid plexus cells produce CSF.

      Microglia are the immune cells of the CNS and play a crucial role in protecting the brain from infection and injury. They also contribute to the maintenance of neuronal health and function.

      In summary, glial cells are essential for the proper functioning of the central nervous system. They provide structural support, nourishment, insulation, and immune defense to neurons, ensuring the health and well-being of the brain and spinal cord.

    • This question is part of the following fields:

      • Neurosciences
      5.5
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  • Question 8 - Which cranial nerve is solely responsible for sensory functions? ...

    Correct

    • Which cranial nerve is solely responsible for sensory functions?

      Your Answer: Vestibulocochlear

      Explanation:

      Overview of Cranial Nerves and Their Functions

      The cranial nerves are a complex system of nerves that originate from the brain and control various functions of the head and neck. There are twelve cranial nerves, each with a specific function and origin. The following table provides a simplified overview of the cranial nerves, including their origin, skull exit, modality, and functions.

      The first cranial nerve, the olfactory nerve, originates from the telencephalon and exits through the cribriform plate. It is a sensory nerve that controls the sense of smell. The second cranial nerve, the optic nerve, originates from the diencephalon and exits through the optic foramen. It is a sensory nerve that controls vision.

      The third cranial nerve, the oculomotor nerve, originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement, pupillary constriction, and lens accommodation. The fourth cranial nerve, the trochlear nerve, also originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement.

      The fifth cranial nerve, the trigeminal nerve, originates from the pons and exits through different foramina depending on the division. It is a mixed nerve that controls chewing and sensation of the anterior 2/3 of the scalp. It also tenses the tympanic membrane to dampen loud noises.

      The sixth cranial nerve, the abducens nerve, originates from the pons and exits through the superior orbital fissure. It is a motor nerve that controls eye movement. The seventh cranial nerve, the facial nerve, also originates from the pons and exits through the internal auditory canal. It is a mixed nerve that controls facial expression, taste of the anterior 2/3 of the tongue, and tension on the stapes to dampen loud noises.

      The eighth cranial nerve, the vestibulocochlear nerve, originates from the pons and exits through the internal auditory canal. It is a sensory nerve that controls hearing. The ninth cranial nerve, the glossopharyngeal nerve, originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls taste of the posterior 1/3 of the tongue, elevation of the larynx and pharynx, and swallowing.

      The tenth cranial nerve, the vagus nerve, also originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls swallowing, voice production, and parasympathetic supply to nearly all thoracic and abdominal viscera. The eleventh cranial nerve, the accessory nerve, originates from the medulla and exits through the jugular foramen. It is a motor nerve that controls shoulder shrugging and head turning.

      The twelfth cranial nerve, the hypoglossal nerve, originates from the medulla and exits through the hypoglossal canal. It is a motor nerve that controls tongue movement. Overall, the cranial nerves play a crucial role in controlling various functions of the head and neck, and any damage of dysfunction can have significant consequences.

    • This question is part of the following fields:

      • Neurosciences
      14.8
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  • Question 9 - Which cranial nerve travels through the cribriform plate of the ethmoid bone on...

    Correct

    • Which cranial nerve travels through the cribriform plate of the ethmoid bone on its way to the brain?

      Your Answer: Olfactory nerve

      Explanation:

      The olfactory nerves are responsible for the sense of smell. They originate in the upper part of the nose’s mucous membrane and travel through the ethmoid bone’s cribriform plate. From there, they reach the olfactory bulb, where nerve cells synapse and transmit the impulse to a second neuron. Finally, the nerves travel to the temporal lobe of the cerebrum, where the perception of smell occurs.

      Overview of Cranial Nerves and Their Functions

      The cranial nerves are a complex system of nerves that originate from the brain and control various functions of the head and neck. There are twelve cranial nerves, each with a specific function and origin. The following table provides a simplified overview of the cranial nerves, including their origin, skull exit, modality, and functions.

      The first cranial nerve, the olfactory nerve, originates from the telencephalon and exits through the cribriform plate. It is a sensory nerve that controls the sense of smell. The second cranial nerve, the optic nerve, originates from the diencephalon and exits through the optic foramen. It is a sensory nerve that controls vision.

      The third cranial nerve, the oculomotor nerve, originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement, pupillary constriction, and lens accommodation. The fourth cranial nerve, the trochlear nerve, also originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement.

      The fifth cranial nerve, the trigeminal nerve, originates from the pons and exits through different foramina depending on the division. It is a mixed nerve that controls chewing and sensation of the anterior 2/3 of the scalp. It also tenses the tympanic membrane to dampen loud noises.

      The sixth cranial nerve, the abducens nerve, originates from the pons and exits through the superior orbital fissure. It is a motor nerve that controls eye movement. The seventh cranial nerve, the facial nerve, also originates from the pons and exits through the internal auditory canal. It is a mixed nerve that controls facial expression, taste of the anterior 2/3 of the tongue, and tension on the stapes to dampen loud noises.

      The eighth cranial nerve, the vestibulocochlear nerve, originates from the pons and exits through the internal auditory canal. It is a sensory nerve that controls hearing. The ninth cranial nerve, the glossopharyngeal nerve, originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls taste of the posterior 1/3 of the tongue, elevation of the larynx and pharynx, and swallowing.

      The tenth cranial nerve, the vagus nerve, also originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls swallowing, voice production, and parasympathetic supply to nearly all thoracic and abdominal viscera. The eleventh cranial nerve, the accessory nerve, originates from the medulla and exits through the jugular foramen. It is a motor nerve that controls shoulder shrugging and head turning.

      The twelfth cranial nerve, the hypoglossal nerve, originates from the medulla and exits through the hypoglossal canal. It is a motor nerve that controls tongue movement. Overall, the cranial nerves play a crucial role in controlling various functions of the head and neck, and any damage of dysfunction can have significant consequences.

    • This question is part of the following fields:

      • Neurosciences
      3.7
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  • Question 10 - What is a true statement about Broca's aphasia? ...

    Correct

    • What is a true statement about Broca's aphasia?

      Your Answer: Main areas affected are Brodmann areas 44 and 45

      Explanation:

      Aphasia is a language impairment that affects the production of comprehension of speech, as well as the ability to read of write. The areas involved in language are situated around the Sylvian fissure, referred to as the ‘perisylvian language area’. For repetition, the primary auditory cortex, Wernicke, Broca via the Arcuate fasciculus (AF), Broca recodes into articulatory plan, primary motor cortex, and pyramidal system to cranial nerves are involved. For oral reading, the visual cortex to Wernicke and the same processes as for repetition follows. For writing, Wernicke via AF to premotor cortex for arm and hand, movement planned, sent to motor cortex. The classification of aphasia is complex and imprecise, with the Boston Group classification and Luria’s aphasia interpretation being the most influential. The important subtypes of aphasia include global aphasia, Broca’s aphasia, Wernicke’s aphasia, conduction aphasia, anomic aphasia, transcortical motor aphasia, and transcortical sensory aphasia. Additional syndromes include alexia without agraphia, alexia with agraphia, and pure word deafness.

    • This question is part of the following fields:

      • Neurosciences
      11.3
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  • Question 11 - What structure is impacted in the pathology of Parkinson's disease? ...

    Correct

    • What structure is impacted in the pathology of Parkinson's disease?

      Your Answer: Substantia nigra

      Explanation:

      Brain Structures and Functions

      The brain is a complex organ that is responsible for controlling various bodily functions. Among the important structures in the brain are the substantia nigra, hippocampus, hypothalamus, pituitary gland, and thalamus.

      The substantia nigra is a part of the basal ganglia located in the midbrain. It contains dopamine-producing neurons that regulate voluntary movement and mood. Parkinson’s disease is associated with the degeneration of the melanin-containing cells in the pars compacta of the substantia nigra.

      The hippocampus is a part of the limbic system that is involved in memory, learning, attention, and information processing.

      The hypothalamus is located at the base of the brain near the pituitary gland. It regulates thirst, hunger, circadian rhythm, emotions, and body temperature. It also controls the pituitary gland by secreting hormones.

      The pituitary gland is a small endocrine organ located below the hypothalamus in the middle of the base of the brain. It controls many bodily functions through the action of hormones and is divided into an anterior lobe, intermediate lobe, and posterior lobe.

      The thalamus is located above the brainstem and processes and relays sensory and motor information.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 12 - How can we differentiate between an organic and functional illness, and what signs...

    Incorrect

    • How can we differentiate between an organic and functional illness, and what signs of symptoms are more indicative of an organic illness?

      Your Answer: Thought block

      Correct Answer: Perseveration

      Explanation:

      Organic processes are indicated by the presence of visual hallucinations.

      Perseveration: The Clinical Symptoms in Chronic Schizophrenia and Organic Dementia

      Perseveration is a common behavior observed in patients with organic brain involvement. It is characterized by the conscious continuation of an act of an idea. This behavior is frequently seen in patients with delirium, epilepsy, dementia, schizophrenia, and normal individuals under extreme fatigue of drug-induced states.

      In chronic schizophrenia and organic dementia, perseveration is a prominent symptom. Patients with these conditions tend to repeat the same words, phrases, of actions over and over again, even when it is no longer appropriate of relevant to the situation. This behavior can be frustrating for caregivers and family members, and it can also interfere with the patient’s ability to communicate effectively.

      In schizophrenia, perseveration is often associated with disorganized thinking and speech. Patients may jump from one topic to another without any logical connection, and they may repeat the same words of phrases in an attempt to express their thoughts. In organic dementia, perseveration is a sign of cognitive decline and memory impairment. Patients may repeat the same stories of questions, forgetting that they have already asked of answered them.

      Overall, perseveration is a common symptom in patients with organic brain involvement, and it can have a significant impact on their daily functioning and quality of life. Understanding this behavior is essential for effective management and treatment of these conditions.

    • This question is part of the following fields:

      • Neurosciences
      32.5
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  • Question 13 - What is the term used to describe the inability to perceive multiple objects...

    Correct

    • What is the term used to describe the inability to perceive multiple objects in the visual field simultaneously?

      Your Answer: Simultanagnosia

      Explanation:

      Agnosia is a condition where a person loses the ability to recognize objects, persons, sounds, shapes, of smells, despite having no significant memory loss of defective senses. There are different types of agnosia, such as prosopagnosia (inability to recognize familiar faces), anosognosia (inability to recognize one’s own condition/illness), autotopagnosia (inability to orient parts of the body), phonagnosia (inability to recognize familiar voices), simultanagnosia (inability to appreciate two objects in the visual field at the same time), and astereoagnosia (inability to recognize objects by touch).

    • This question is part of the following fields:

      • Neurosciences
      7.7
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  • Question 14 - A 62-year-old man experiences a stroke caused by a ruptured berry aneurysm in...

    Incorrect

    • A 62-year-old man experiences a stroke caused by a ruptured berry aneurysm in the middle cerebral artery, resulting in damage to the temporal lobe. What tests would you anticipate to show abnormalities?

      Your Answer: Three object recall

      Correct Answer: Copying intersecting pentagons

      Explanation:

      When the parietal lobe is not functioning properly, it can cause constructional apraxia. This condition makes it difficult for individuals to replicate the intersecting pentagons, which is a common cognitive test included in Folstein’s mini-mental state examination.

    • This question is part of the following fields:

      • Neurosciences
      26.5
      Seconds
  • Question 15 - Which of the following indicates the presence of a dominant parietal lobe injury?...

    Incorrect

    • Which of the following indicates the presence of a dominant parietal lobe injury?

      Your Answer:

      Correct Answer: Finger agnosia

      Explanation:

      Parietal Lobe Dysfunction: Types and Symptoms

      The parietal lobe is a part of the brain that plays a crucial role in processing sensory information and integrating it with other cognitive functions. Dysfunction in this area can lead to various symptoms, depending on the location and extent of the damage.

      Dominant parietal lobe dysfunction, often caused by a stroke, can result in Gerstmann’s syndrome, which includes finger agnosia, dyscalculia, dysgraphia, and right-left disorientation. Non-dominant parietal lobe dysfunction, on the other hand, can cause anosognosia, dressing apraxia, spatial neglect, and constructional apraxia.

      Bilateral damage to the parieto-occipital lobes, a rare condition, can lead to Balint’s syndrome, which is characterized by oculomotor apraxia, optic ataxia, and simultanagnosia. These symptoms can affect a person’s ability to shift gaze, interact with objects, and perceive multiple objects at once.

      In summary, parietal lobe dysfunction can manifest in various ways, and understanding the specific symptoms can help diagnose and treat the underlying condition.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 16 - If a patient suspected of having a stroke presents with a deviation of...

    Incorrect

    • If a patient suspected of having a stroke presents with a deviation of the tongue towards the right, which nerve is likely to be impacted?

      Your Answer:

      Correct Answer: Right hypoglossal nerve

      Explanation:

      The hypoglossal nerve (nerve XII) is responsible for controlling the motor functions of the tongue and the muscles surrounding the hyoid bone. As a result, when there is a lesion on the right side, the tongue will tend to deviate towards that side. It is important to note that the hypoglossal nerve is purely a motor nerve and does not have any sensory component.

      Overview of Cranial Nerves and Their Functions

      The cranial nerves are a complex system of nerves that originate from the brain and control various functions of the head and neck. There are twelve cranial nerves, each with a specific function and origin. The following table provides a simplified overview of the cranial nerves, including their origin, skull exit, modality, and functions.

      The first cranial nerve, the olfactory nerve, originates from the telencephalon and exits through the cribriform plate. It is a sensory nerve that controls the sense of smell. The second cranial nerve, the optic nerve, originates from the diencephalon and exits through the optic foramen. It is a sensory nerve that controls vision.

      The third cranial nerve, the oculomotor nerve, originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement, pupillary constriction, and lens accommodation. The fourth cranial nerve, the trochlear nerve, also originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement.

      The fifth cranial nerve, the trigeminal nerve, originates from the pons and exits through different foramina depending on the division. It is a mixed nerve that controls chewing and sensation of the anterior 2/3 of the scalp. It also tenses the tympanic membrane to dampen loud noises.

      The sixth cranial nerve, the abducens nerve, originates from the pons and exits through the superior orbital fissure. It is a motor nerve that controls eye movement. The seventh cranial nerve, the facial nerve, also originates from the pons and exits through the internal auditory canal. It is a mixed nerve that controls facial expression, taste of the anterior 2/3 of the tongue, and tension on the stapes to dampen loud noises.

      The eighth cranial nerve, the vestibulocochlear nerve, originates from the pons and exits through the internal auditory canal. It is a sensory nerve that controls hearing. The ninth cranial nerve, the glossopharyngeal nerve, originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls taste of the posterior 1/3 of the tongue, elevation of the larynx and pharynx, and swallowing.

      The tenth cranial nerve, the vagus nerve, also originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls swallowing, voice production, and parasympathetic supply to nearly all thoracic and abdominal viscera. The eleventh cranial nerve, the accessory nerve, originates from the medulla and exits through the jugular foramen. It is a motor nerve that controls shoulder shrugging and head turning.

      The twelfth cranial nerve, the hypoglossal nerve, originates from the medulla and exits through the hypoglossal canal. It is a motor nerve that controls tongue movement. Overall, the cranial nerves play a crucial role in controlling various functions of the head and neck, and any damage of dysfunction can have significant consequences.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 17 - If a certain nerve is damaged, which reflex may not occur during the...

    Incorrect

    • If a certain nerve is damaged, which reflex may not occur during the jaw jerk test?

      Your Answer:

      Correct Answer: Trigeminal

      Explanation:

      Cranial Nerve Reflexes

      When it comes to questions on cranial nerve reflexes, it is important to match the reflex to the nerves involved. Here are some examples:

      – Pupillary light reflex: involves the optic nerve (sensory) and oculomotor nerve (motor).
      – Accommodation reflex: involves the optic nerve (sensory) and oculomotor nerve (motor).
      – Jaw jerk: involves the trigeminal nerve (sensory and motor).
      – Corneal reflex: involves the trigeminal nerve (sensory) and facial nerve (motor).
      – Vestibulo-ocular reflex: involves the vestibulocochlear nerve (sensory) and oculomotor, trochlear, and abducent nerves (motor).

      Another example of a cranial nerve reflex is the gag reflex, which involves the glossopharyngeal nerve (sensory) and the vagus nerve (motor). This reflex is important for protecting the airway from foreign objects of substances that may trigger a gag reflex. It is also used as a diagnostic tool to assess the function of these nerves.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 18 - Which process breaks down dopamine? ...

    Incorrect

    • Which process breaks down dopamine?

      Your Answer:

      Correct Answer: COMT and both forms of MAO

      Explanation:

      COMT and both types of MAO are responsible for the metabolism of dopamine.

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 19 - What waveform represents a frequency range of 12-30Hz? ...

    Incorrect

    • What waveform represents a frequency range of 12-30Hz?

      Your Answer:

      Correct Answer: Beta

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 20 - What is a common target for deep brain stimulation (DBS) in individuals with...

    Incorrect

    • What is a common target for deep brain stimulation (DBS) in individuals with Parkinson's disease?

      Your Answer:

      Correct Answer: Globus pallidus interna

      Explanation:

      DBS is primarily used to treat Parkinson’s disease by targeting the Globus pallidus interna and subthalamic nucleus. However, for treatment-resistant depression (TRD), the subcallosal cingulate was the first area investigated for DBS, while vagal nerve stimulation has also been used. Psychosurgical treatment for refractory OCD and TRD involves targeting the anterior limb of the internal capsule. Although the caudate nucleus is part of the basal ganglia and associated with Parkinson’s disease, it is not a primary target for DBS.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 21 - Which condition is most commonly associated with fast, generalized spike and wave activity...

    Incorrect

    • Which condition is most commonly associated with fast, generalized spike and wave activity on the EEG?

      Your Answer:

      Correct Answer: Myoclonic epilepsy

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 22 - What type of dysarthria is typically caused by widespread damage to the upper...

    Incorrect

    • What type of dysarthria is typically caused by widespread damage to the upper motor neurons?

      Your Answer:

      Correct Answer: Spastic dysarthria

      Explanation:

      Dysarthria is a speech disorder that affects the volume, rate, tone, of quality of spoken language. There are different types of dysarthria, each with its own set of features, associated conditions, and localisation. The types of dysarthria include spastic, flaccid, hypokinetic, hyperkinetic, and ataxic.

      Spastic dysarthria is characterised by explosive and forceful speech at a slow rate and is associated with conditions such as pseudobulbar palsy and spastic hemiplegia.

      Flaccid dysarthria, on the other hand, is characterised by a breathy, nasal voice and imprecise consonants and is associated with conditions such as myasthenia gravis.

      Hypokinetic dysarthria is characterised by slow, quiet speech with a tremor and is associated with conditions such as Parkinson’s disease.

      Hyperkinetic dysarthria is characterised by a variable rate, inappropriate stoppages, and a strained quality and is associated with conditions such as Huntington’s disease, Sydenham’s chorea, and tardive dyskinesia.

      Finally, ataxic dysarthria is characterised by rapid, monopitched, and slurred speech and is associated with conditions such as Friedreich’s ataxia and alcohol abuse. The localisation of each type of dysarthria varies, with spastic and flaccid dysarthria affecting the upper and lower motor neurons, respectively, and hypokinetic, hyperkinetic, and ataxic dysarthria affecting the extrapyramidal and cerebellar regions of the brain.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 23 - Which cognitive function is thought to be essential for the ventromedial prefrontal cortex?...

    Incorrect

    • Which cognitive function is thought to be essential for the ventromedial prefrontal cortex?

      Your Answer:

      Correct Answer: Moral judgement

      Explanation:

      The Neuroscience of Morality

      Morality is a process that involves both instinctive feelings and rational judgement. The ventromedial prefrontal cortex (PFC) is responsible for the emotional baseline, while the dorsolateral PFC is involved in cognitive control and problem solving. Studies have shown that the ventromedial PFC is activated during the solving of moral problems, particularly when responding to emotionally charged scenarios. On the other hand, the dorsolateral PFC is involved in tamping down our innate, reactionary moral system. These findings suggest that morality is a dual process event that involves both emotional and cognitive systems in the brain.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 24 - What is a true statement about Anton-Babinski syndrome? ...

    Incorrect

    • What is a true statement about Anton-Babinski syndrome?

      Your Answer:

      Correct Answer: Confabulation is a characteristic feature

      Explanation:

      Anton’s syndrome, also known as Anton-Babinski syndrome, is a condition that results from damage to the occipital lobe. People with this syndrome are cortically blind, but they are not aware of it and deny having any problem, a condition known as anosognosia. They may start falling over furniture as they cannot see, but they believe they can still see and describe their surroundings in detail, even though their descriptions are incorrect (confabulation). This syndrome is characterized by a lack of awareness of visual impairment, which can lead to significant difficulties in daily life.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 25 - Which of the following is categorized as a projection tract in relation to...

    Incorrect

    • Which of the following is categorized as a projection tract in relation to white matter?

      Your Answer:

      Correct Answer: Geniculocalcarine tract

      Explanation:

      White matter is the cabling that links different parts of the CNS together. There are three types of white matter cables: projection tracts, commissural tracts, and association tracts. Projection tracts connect higher centers of the brain with lower centers, commissural tracts connect the two hemispheres together, and association tracts connect regions of the same hemisphere. Some common tracts include the corticospinal tract, which connects the motor cortex to the brainstem and spinal cord, and the corpus callosum, which is the largest white matter fiber bundle connecting corresponding areas of cortex between the hemispheres. Other tracts include the cingulum, superior and inferior occipitofrontal fasciculi, and the superior and inferior longitudinal fasciculi.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 26 - What substances are found at higher levels in individuals with depression and bipolar...

    Incorrect

    • What substances are found at higher levels in individuals with depression and bipolar affective disorder?

      Your Answer:

      Correct Answer: Cortisol

      Explanation:

      HPA Axis Dysfunction in Mood Disorders

      The HPA axis, which includes regulatory neural inputs and a feedback loop involving the hypothalamus, pituitary, and adrenal glands, plays a central role in the stress response. Excessive secretion of cortisol, a glucocorticoid hormone, can lead to disruptions in cellular functioning and widespread physiologic dysfunction. Dysregulation of the HPA axis is implicated in mood disorders such as depression and bipolar affective disorder.

      In depressed patients, cortisol levels often do not decrease as expected in response to the administration of dexamethasone, a synthetic corticosteroid. This abnormality in the dexamethasone suppression test is thought to be linked to genetic of acquired defects of glucocorticoid receptors. Tricyclic antidepressants have been shown to increase expression of glucocorticoid receptors, whereas this is not the case for SSRIs.

      Early adverse experiences can produce long standing changes in HPA axis regulation, indicating a possible neurobiological mechanism whereby childhood trauma could be translated into increased vulnerability to mood disorder. In major depression, there is hypersecretion of cortisol, corticotropin-releasing factor (CRF), and ACTH, and associated adrenocortical enlargement. HPA abnormalities have also been found in other psychiatric disorders including Alzheimer’s and PTSD.

      In bipolar disorder, dysregulation of ACTH and cortisol response after CRH stimulation have been reported. Abnormal DST results are found more often during depressive episodes in the course of bipolar disorder than in unipolar disorder. Reduced pituitary volume secondary to LHPA stimulation, resulting in pituitary hypoactivity, has been observed in bipolar patients.

      Overall, HPA axis dysfunction is implicated in mood disorders, and understanding the underlying mechanisms may lead to new opportunities for treatments.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 27 - Which of the following is believed to be caused by the obstruction of...

    Incorrect

    • Which of the following is believed to be caused by the obstruction of D-2 receptors in the mesolimbic pathway?

      Your Answer:

      Correct Answer: The therapeutic effects of antipsychotics in schizophrenia

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 28 - Which artery is likely to be affected if a patient is unable to...

    Incorrect

    • Which artery is likely to be affected if a patient is unable to read but can still write after experiencing a stroke?

      Your Answer:

      Correct Answer: Left posterior cerebral

      Explanation:

      An infarction to the left posterior cerebral artery typically results in pure alexia, also known as alexia without agraphia, which is characterized by the inability to read but the ability to write.

      Brain Blood Supply and Consequences of Occlusion

      The brain receives blood supply from the internal carotid and vertebral arteries, which form the circle of Willis. The circle of Willis acts as a shunt system in case of vessel damage. The three main vessels arising from the circle are the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA). Occlusion of these vessels can result in various neurological deficits. ACA occlusion may cause hemiparesis of the contralateral foot and leg, sensory loss, and frontal signs. MCA occlusion is the most common and can lead to hemiparesis, dysphasia/aphasia, neglect, and visual field defects. PCA occlusion may cause alexia, loss of sensation, hemianopia, prosopagnosia, and cranial nerve defects. It is important to recognize these consequences to provide appropriate treatment.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 29 - What waveform represents a frequency range of 4-8 Hz? ...

    Incorrect

    • What waveform represents a frequency range of 4-8 Hz?

      Your Answer:

      Correct Answer: Theta

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 30 - What is the structure that carries the middle meningeal artery? ...

    Incorrect

    • What is the structure that carries the middle meningeal artery?

      Your Answer:

      Correct Answer: Foramen spinosum

      Explanation:

      Cranial Fossae and Foramina

      The cranium is divided into three regions known as fossae, each housing different cranial lobes. The anterior cranial fossa contains the frontal lobes and includes the frontal and ethmoid bones, as well as the lesser wing of the sphenoid. The middle cranial fossa contains the temporal lobes and includes the greater wing of the sphenoid, sella turcica, and most of the temporal bones. The posterior cranial fossa contains the occipital lobes, cerebellum, and medulla and includes the occipital bone.

      There are several foramina in the skull that allow for the passage of various structures. The most important foramina likely to appear in exams are listed below:

      – Foramen spinosum: located in the middle fossa and allows for the passage of the middle meningeal artery.
      – Foramen ovale: located in the middle fossa and allows for the passage of the mandibular division of the trigeminal nerve.
      – Foramen lacerum: located in the middle fossa and allows for the passage of the small meningeal branches of the ascending pharyngeal artery and emissary veins from the cavernous sinus.
      – Foramen magnum: located in the posterior fossa and allows for the passage of the spinal cord.
      – Jugular foramen: located in the posterior fossa and allows for the passage of cranial nerves IX, X, and XI.

      Understanding the location and function of these foramina is essential for medical professionals, as they play a crucial role in the diagnosis and treatment of various neurological conditions.

    • This question is part of the following fields:

      • Neurosciences
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      Seconds
  • Question 31 - Which substance has the highest level of permeability through the blood brain barrier?...

    Incorrect

    • Which substance has the highest level of permeability through the blood brain barrier?

      Your Answer:

      Correct Answer: Lipid soluble molecules

      Explanation:

      Understanding the Blood Brain Barrier

      The blood brain barrier (BBB) is a crucial component of the brain’s defense system against harmful chemicals and ion imbalances. It is a semi-permeable membrane formed by tight junctions of endothelial cells in the brain’s capillaries, which separates the blood from the cerebrospinal fluid. However, certain areas of the BBB, known as circumventricular organs, are fenestrated to allow neurosecretory products to enter the blood.

      When it comes to MRCPsych questions, the focus is on the following aspects of the BBB: the tight junctions between endothelial cells, the ease with which lipid-soluble molecules pass through compared to water-soluble ones, the difficulty large and highly charged molecules face in passing through, the increased permeability of the BBB during inflammation, and the theoretical ability of nasally administered drugs to bypass the BBB.

      It is important to remember the specific circumventricular organs where the BBB is fenestrated, including the posterior pituitary and the area postrema. Understanding the BBB’s function and characteristics is essential for medical professionals to diagnose and treat neurological disorders effectively.

    • This question is part of the following fields:

      • Neurosciences
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      Seconds
  • Question 32 - Which language assessment is considered a neuropsychological test? ...

    Incorrect

    • Which language assessment is considered a neuropsychological test?

      Your Answer:

      Correct Answer: Token test

      Explanation:

      The neuropsychological assessment includes the token test, which is a language test that uses various tokens, such as differently coloured rectangles and circular discs. The subject is given verbal instructions of increasing complexity to perform tasks with these tokens, and it is a sensitive measure of language comprehension impairment, particularly in cases of aphasia. Additionally, there are several tests of executive function that assess frontal lobe function, including the Stroop test, Tower of London test, Wisconsin card sorting test, Cognitive estimates test, Six elements test, Multiple errands task, and Trails making test.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 33 - What cell type plays a significant role in the formation of the blood-brain...

    Incorrect

    • What cell type plays a significant role in the formation of the blood-brain barrier?

      Your Answer:

      Correct Answer: Astrocyte

      Explanation:

      Glial Cells: The Support System of the Central Nervous System

      The central nervous system is composed of two basic cell types: neurons and glial cells. Glial cells, also known as support cells, play a crucial role in maintaining the health and function of neurons. There are several types of glial cells, including macroglia (astrocytes and oligodendrocytes), ependymal cells, and microglia.

      Astrocytes are the most abundant type of glial cell and have numerous functions, such as providing structural support, repairing nervous tissue, nourishing neurons, contributing to the blood-brain barrier, and regulating neurotransmission and blood flow. There are two main types of astrocytes: protoplasmic and fibrous.

      Oligodendrocytes are responsible for the formation of myelin sheaths, which insulate and protect axons, allowing for faster and more efficient transmission of nerve impulses.

      Ependymal cells line the ventricular system and are involved in the circulation of cerebrospinal fluid (CSF) and fluid homeostasis in the brain. Specialized ependymal cells called choroid plexus cells produce CSF.

      Microglia are the immune cells of the CNS and play a crucial role in protecting the brain from infection and injury. They also contribute to the maintenance of neuronal health and function.

      In summary, glial cells are essential for the proper functioning of the central nervous system. They provide structural support, nourishment, insulation, and immune defense to neurons, ensuring the health and well-being of the brain and spinal cord.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 34 - Which receptor functions as an ionotropic receptor? ...

    Incorrect

    • Which receptor functions as an ionotropic receptor?

      Your Answer:

      Correct Answer: 5HT-3

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 35 - Which of the following is a catecholamine? ...

    Incorrect

    • Which of the following is a catecholamine?

      Your Answer:

      Correct Answer: Adrenaline

      Explanation:

      Catecholamines are a group of chemical compounds that have a distinct structure consisting of a benzene ring with two hydroxyl groups, an intermediate ethyl chain, and a terminal amine group. These compounds play an important role in the body and are involved in various physiological processes. The three main catecholamines found in the body are dopamine, adrenaline, and noradrenaline. All of these compounds are derived from the amino acid tyrosine. Overall, catecholamines are essential for maintaining proper bodily functions and are involved in a wide range of physiological processes.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 36 - In which type of condition of disease are Hirano bodies typically observed? ...

    Incorrect

    • In which type of condition of disease are Hirano bodies typically observed?

      Your Answer:

      Correct Answer: Alzheimer's

      Explanation:

      Hirano bodies are a nonspecific indication of neurodegeneration and are primarily observed in.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 37 - Which type of injury of damage typically leads to utilization behaviour? ...

    Incorrect

    • Which type of injury of damage typically leads to utilization behaviour?

      Your Answer:

      Correct Answer: Frontal lobe

      Explanation:

      Abnormal Motor Behaviours Associated with Utilization Behaviour

      Utilization behaviour (UB) is a condition where patients exhibit exaggerated and inappropriate motor responses to environmental cues and objects. This behaviour is automatic and instrumentally correct, but not contextually appropriate. For instance, a patient may start brushing their teeth when presented with a toothbrush, even in a setting where it is not expected. UB is caused by frontal lobe lesions that result in a loss of inhibitory control.

      Other motor abnormalities associated with UB include imitation behaviour, where patients tend to imitate the examiner’s behaviour, and the alien hand sign, where patients experience bizarre hand movements that they cannot control. Manual groping behaviour is also observed, where patients automatically manipulate objects placed in front of them. The grasp reflex, which is normal in infants, should not be present in children and adults. It is an automatic tendency to grip objects of stimuli, such as the examiner’s hand.

      Environmental Dependency Syndrome is another condition associated with UB. It describes deficits in personal control of action and an overreliance on social and physical environmental stimuli to guide behaviour in a social context. For example, a patient may start commenting on pictures in an examiner’s office, believing it to be an art gallery.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 38 - A woman comes to the clinic with a sudden loss of vision in...

    Incorrect

    • A woman comes to the clinic with a sudden loss of vision in both eyes. There are no abnormalities in the front part of the eye of the back part of the eye, and her pupils react normally to light. What is the most probable location of the blockage in the artery?

      Your Answer:

      Correct Answer: Posterior cerebral arteries

      Explanation:

      Bilateral infarction in the territory supplied by the distal posterior cerebral arteries can lead to cortical blindness with preserved pupillary reflex. This condition is often accompanied by Anton’s syndrome, where patients are unaware of their blindness.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 39 - What hormone is produced by the posterior pituitary gland? ...

    Incorrect

    • What hormone is produced by the posterior pituitary gland?

      Your Answer:

      Correct Answer: Antidiuretic hormone (ADH)

      Explanation:

      The posterior pituitary secretes antidiuretic hormone (ADH) and oxytocin, while the anterior pituitary secretes human growth hormone (HGH), adrenocorticotropic hormone (ACTH), prolactin (PRL), thyroid-stimulating hormone (TSH), luteinising hormone (LH), and follicle-stimulating hormone (FSH).

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 40 - What is a true statement about dopamine receptors? ...

    Incorrect

    • What is a true statement about dopamine receptors?

      Your Answer:

      Correct Answer: Activation of D1 receptors activates adenylyl cyclase

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 41 - Which condition is typically associated with a flattened EEG trace? ...

    Incorrect

    • Which condition is typically associated with a flattened EEG trace?

      Your Answer:

      Correct Answer: Huntington's

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 42 - Which feature is not associated with Gerstmann's syndrome? ...

    Incorrect

    • Which feature is not associated with Gerstmann's syndrome?

      Your Answer:

      Correct Answer: Anosognosia

      Explanation:

      Non-dominant parietal lobe dysfunction is indicated by the presence of anosognosia.

      Parietal Lobe Dysfunction: Types and Symptoms

      The parietal lobe is a part of the brain that plays a crucial role in processing sensory information and integrating it with other cognitive functions. Dysfunction in this area can lead to various symptoms, depending on the location and extent of the damage.

      Dominant parietal lobe dysfunction, often caused by a stroke, can result in Gerstmann’s syndrome, which includes finger agnosia, dyscalculia, dysgraphia, and right-left disorientation. Non-dominant parietal lobe dysfunction, on the other hand, can cause anosognosia, dressing apraxia, spatial neglect, and constructional apraxia.

      Bilateral damage to the parieto-occipital lobes, a rare condition, can lead to Balint’s syndrome, which is characterized by oculomotor apraxia, optic ataxia, and simultanagnosia. These symptoms can affect a person’s ability to shift gaze, interact with objects, and perceive multiple objects at once.

      In summary, parietal lobe dysfunction can manifest in various ways, and understanding the specific symptoms can help diagnose and treat the underlying condition.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 43 - I'm sorry, as an AI language model, I cannot provide an answer without...

    Incorrect

    • I'm sorry, as an AI language model, I cannot provide an answer without additional context. Please provide more information of clarify your question.

      Your Answer:

      Correct Answer: Wernicke's aphasia

      Explanation:

      Aphasia is a language impairment that affects the production of comprehension of speech, as well as the ability to read of write. The areas involved in language are situated around the Sylvian fissure, referred to as the ‘perisylvian language area’. For repetition, the primary auditory cortex, Wernicke, Broca via the Arcuate fasciculus (AF), Broca recodes into articulatory plan, primary motor cortex, and pyramidal system to cranial nerves are involved. For oral reading, the visual cortex to Wernicke and the same processes as for repetition follows. For writing, Wernicke via AF to premotor cortex for arm and hand, movement planned, sent to motor cortex. The classification of aphasia is complex and imprecise, with the Boston Group classification and Luria’s aphasia interpretation being the most influential. The important subtypes of aphasia include global aphasia, Broca’s aphasia, Wernicke’s aphasia, conduction aphasia, anomic aphasia, transcortical motor aphasia, and transcortical sensory aphasia. Additional syndromes include alexia without agraphia, alexia with agraphia, and pure word deafness.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 44 - What is the neuroanatomical structure that was named after a seahorse due to...

    Incorrect

    • What is the neuroanatomical structure that was named after a seahorse due to its alleged resemblance?

      Your Answer:

      Correct Answer: Hippocampus

      Explanation:

      Brain Structures and Their Etymologies

      The hippocampus, with its swirling shape, was named after the seahorse, combining the Greek words ‘hippos’ (horse) and ‘kampos’ (sea-monster). Meanwhile, the cerebellum, which resembles a smaller version of the brain, was named after the Latin word for ‘little brain’. The corpus callosum, a bundle of nerve fibers connecting the two hemispheres of the brain, was named after the Latin for ‘tough body’. The hypothalamus, located below the thalamus, was named after its position. Finally, the putamen, a structure involved in movement control, comes from the Latin word for ‘that which falls off in pruning’. These etymologies provide insight into the history and development of our understanding of the brain’s structures.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 45 - What is the association with theta rhythms? ...

    Incorrect

    • What is the association with theta rhythms?

      Your Answer:

      Correct Answer: Seen in meditative practice

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 46 - What methods are used to generate estimates of white matter tracts? ...

    Incorrect

    • What methods are used to generate estimates of white matter tracts?

      Your Answer:

      Correct Answer: DTI

      Explanation:

      Neuroimaging techniques can be divided into structural and functional types, although this distinction is becoming less clear as new techniques emerge. Structural techniques include computed tomography (CT) and magnetic resonance imaging (MRI), which use x-rays and magnetic fields, respectively, to produce images of the brain’s structure. Functional techniques, on the other hand, measure brain activity by detecting changes in blood flow of oxygen consumption. These include functional MRI (fMRI), emission tomography (PET and SPECT), perfusion MRI (pMRI), and magnetic resonance spectroscopy (MRS). Some techniques, such as diffusion tensor imaging (DTI), combine both structural and functional information to provide a more complete picture of the brain’s anatomy and function. DTI, for example, uses MRI to estimate the paths that water takes as it diffuses through white matter, allowing researchers to visualize white matter tracts.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 47 - Which imaging technique is not considered functional? ...

    Incorrect

    • Which imaging technique is not considered functional?

      Your Answer:

      Correct Answer: CT

      Explanation:

      Neuroimaging techniques can be divided into structural and functional types, although this distinction is becoming less clear as new techniques emerge. Structural techniques include computed tomography (CT) and magnetic resonance imaging (MRI), which use x-rays and magnetic fields, respectively, to produce images of the brain’s structure. Functional techniques, on the other hand, measure brain activity by detecting changes in blood flow of oxygen consumption. These include functional MRI (fMRI), emission tomography (PET and SPECT), perfusion MRI (pMRI), and magnetic resonance spectroscopy (MRS). Some techniques, such as diffusion tensor imaging (DTI), combine both structural and functional information to provide a more complete picture of the brain’s anatomy and function. DTI, for example, uses MRI to estimate the paths that water takes as it diffuses through white matter, allowing researchers to visualize white matter tracts.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 48 - What is the closest estimate of the membrane potential of a cell at...

    Incorrect

    • What is the closest estimate of the membrane potential of a cell at rest?

      Your Answer:

      Correct Answer: -70 mV

      Explanation:

      Understanding Action Potentials in Neurons and Muscle Cells

      The membrane potential is a crucial aspect of cell physiology, and it exists across the plasma membrane of most cells. However, in neurons and muscle cells, this membrane potential can change over time. When a cell is not stimulated, it is in a resting state, and the inside of the cell is negatively charged compared to the outside. This resting membrane potential is typically around -70mV, and it is maintained by the Na/K pump, which maintains a high concentration of Na outside and K inside the cell.

      To trigger an action potential, the membrane potential must be raised to around -55mV. This can occur when a neurotransmitter binds to the postsynaptic neuron and opens some ion channels. Once the membrane potential reaches -55mV, a cascade of events is initiated, leading to the opening of a large number of Na channels and causing the cell to depolarize. As the membrane potential reaches around +40 mV, the Na channels close, and the K gates open, allowing K to flood out of the cell and causing the membrane potential to fall back down. This process is irreversible and is critical for the transmission of signals in neurons and the contraction of muscle cells.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 49 - An older woman presents to the emergency department with sudden onset of left...

    Incorrect

    • An older woman presents to the emergency department with sudden onset of left leg dysfunction, urinary incontinence, and abulia. As her time in the department progresses, her left arm also becomes affected. She has a history of vascular disease. Which artery do you suspect is involved?

      Your Answer:

      Correct Answer: Anterior cerebral artery

      Explanation:

      When there is a blockage in the anterior cerebral artery, the legs are typically impacted more than the arms. Additionally, a common symptom is abulia, which is a lack of determination of difficulty making firm decisions.

      Brain Blood Supply and Consequences of Occlusion

      The brain receives blood supply from the internal carotid and vertebral arteries, which form the circle of Willis. The circle of Willis acts as a shunt system in case of vessel damage. The three main vessels arising from the circle are the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA). Occlusion of these vessels can result in various neurological deficits. ACA occlusion may cause hemiparesis of the contralateral foot and leg, sensory loss, and frontal signs. MCA occlusion is the most common and can lead to hemiparesis, dysphasia/aphasia, neglect, and visual field defects. PCA occlusion may cause alexia, loss of sensation, hemianopia, prosopagnosia, and cranial nerve defects. It is important to recognize these consequences to provide appropriate treatment.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 50 - Which type of brain lesion is typically associated with Alexia without agraphia? ...

    Incorrect

    • Which type of brain lesion is typically associated with Alexia without agraphia?

      Your Answer:

      Correct Answer: Posterior cerebral artery

      Explanation:

      Aphasia is a language impairment that affects the production of comprehension of speech, as well as the ability to read of write. The areas involved in language are situated around the Sylvian fissure, referred to as the ‘perisylvian language area’. For repetition, the primary auditory cortex, Wernicke, Broca via the Arcuate fasciculus (AF), Broca recodes into articulatory plan, primary motor cortex, and pyramidal system to cranial nerves are involved. For oral reading, the visual cortex to Wernicke and the same processes as for repetition follows. For writing, Wernicke via AF to premotor cortex for arm and hand, movement planned, sent to motor cortex. The classification of aphasia is complex and imprecise, with the Boston Group classification and Luria’s aphasia interpretation being the most influential. The important subtypes of aphasia include global aphasia, Broca’s aphasia, Wernicke’s aphasia, conduction aphasia, anomic aphasia, transcortical motor aphasia, and transcortical sensory aphasia. Additional syndromes include alexia without agraphia, alexia with agraphia, and pure word deafness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 51 - Which statement accurately describes the neurobiology of schizophrenia? ...

    Incorrect

    • Which statement accurately describes the neurobiology of schizophrenia?

      Your Answer:

      Correct Answer: Structural brain abnormalities are present at the onset of illness

      Explanation:

      Schizophrenia is a pathology that is characterized by a number of structural and functional brain alterations. Structural alterations include enlargement of the ventricles, reductions in total brain and gray matter volume, and regional reductions in the amygdala, parahippocampal gyrus, and temporal lobes. Antipsychotic treatment may be associated with gray matter loss over time, and even drug-naïve patients show volume reductions. Cerebral asymmetry is also reduced in affected individuals and healthy relatives. Functional alterations include diminished activation of frontal regions during cognitive tasks and increased activation of temporal regions during hallucinations. These findings suggest that schizophrenia is associated with both macroscopic and functional changes in the brain.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 52 - In which part of the skull is the structure located in the posterior...

    Incorrect

    • In which part of the skull is the structure located in the posterior cranial fossa?

      Your Answer:

      Correct Answer: Foramen magnum

      Explanation:

      The base of the skull contains a sizable opening called the foramen magnum, which permits the spinal cord to pass through.

      Cranial Fossae and Foramina

      The cranium is divided into three regions known as fossae, each housing different cranial lobes. The anterior cranial fossa contains the frontal lobes and includes the frontal and ethmoid bones, as well as the lesser wing of the sphenoid. The middle cranial fossa contains the temporal lobes and includes the greater wing of the sphenoid, sella turcica, and most of the temporal bones. The posterior cranial fossa contains the occipital lobes, cerebellum, and medulla and includes the occipital bone.

      There are several foramina in the skull that allow for the passage of various structures. The most important foramina likely to appear in exams are listed below:

      – Foramen spinosum: located in the middle fossa and allows for the passage of the middle meningeal artery.
      – Foramen ovale: located in the middle fossa and allows for the passage of the mandibular division of the trigeminal nerve.
      – Foramen lacerum: located in the middle fossa and allows for the passage of the small meningeal branches of the ascending pharyngeal artery and emissary veins from the cavernous sinus.
      – Foramen magnum: located in the posterior fossa and allows for the passage of the spinal cord.
      – Jugular foramen: located in the posterior fossa and allows for the passage of cranial nerves IX, X, and XI.

      Understanding the location and function of these foramina is essential for medical professionals, as they play a crucial role in the diagnosis and treatment of various neurological conditions.

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      • Neurosciences
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  • Question 53 - Which interleukin has been consistently found to be present in higher levels in...

    Incorrect

    • Which interleukin has been consistently found to be present in higher levels in individuals with depression compared to those without depression?

      Your Answer:

      Correct Answer: IL-6

      Explanation:

      Inflammatory Cytokines and Mental Health

      Research has suggested that an imbalance in the immune system, particularly the pro-inflammatory cytokines, may play a significant role in the development of common mental disorders. The strongest evidence is found in depression, where studies have shown increased levels of inflammatory markers, such as interleukin-6 (IL-6), tumour necrosis factor-α (TNF-α), and c-reactive protein (CRP), in depressed individuals compared to healthy controls (Santoft, 2020).

      While most studies have focused on the differences in inflammatory markers between depressed and healthy individuals, some have also found a correlation between higher levels of inflammation and more severe depressive symptoms. The underlying cause of this chronic low-grade inflammation is not yet fully understood, but potential factors include psychosocial stress, physical inactivity, poor diet, smoking, obesity, altered gut permeability, disturbed sleep, and vitamin D deficiency.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 54 - Which serotonin receptor is associated with regulating circadian rhythms? ...

    Incorrect

    • Which serotonin receptor is associated with regulating circadian rhythms?

      Your Answer:

      Correct Answer: 5HT-7

      Explanation:

      Serotonin (5-hydroxytryptamine, 5-HT) receptors are primarily G protein receptors, except for 5-HT3, which is a ligand-gated receptor. It is important to remember that 5-HT3 is most commonly associated with nausea. Additionally, 5-HT7 is linked to circadian rhythms. The stimulation of 5-HT2 receptors is believed to be responsible for the side effects of insomnia, agitation, and sexual dysfunction that are associated with the use of selective serotonin reuptake inhibitors (SSRIs).

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      • Neurosciences
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  • Question 55 - What is the other structure that, along with the putamen, comprises the lenticular...

    Incorrect

    • What is the other structure that, along with the putamen, comprises the lenticular nucleus?

      Your Answer:

      Correct Answer: Globus pallidus

      Explanation:

      The Edinger-Westphal nucleus is the motor nucleus of the third cranial nerve, while the putamen and globus pallidus comprise the lenticular nucleus, which is part of the basal ganglia. The basal ganglia play a role in motor control and use the inhibitory neurotransmitter GABA. The components of the basal ganglia can be classified in various ways, with the corpus striatum (caudate nucleus, putamen, nucleus accumbens, and globus pallidus) and the striatum of neostriatum (caudate, putamen, and globus pallidus) being common groupings.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 56 - You are evaluating a 72-year-old man in your office who had a stroke...

    Incorrect

    • You are evaluating a 72-year-old man in your office who had a stroke four weeks ago. His wife reports that he is having difficulty recognizing familiar faces, but is otherwise functioning normally. What is the most appropriate term for his condition?

      Your Answer:

      Correct Answer: Prosopagnosia

      Explanation:

      Prosopagnosia is a condition where individuals are unable to recognize familiar faces, which can be caused by damage to the fusiform area of be congenital. Achromatopsia, on the other hand, is color blindness that can result from thalamus damage. Parietal lobe lesions can cause agraphesthesia, which is the inability to recognize numbers of letters traced on the palm, and astereognosis, which is the inability to recognize an item by touch. Lastly, phonagnosia is the inability to recognize familiar voices and is the auditory equivalent of prosopagnosia, although it is not as well-researched.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 57 - Which area of the central nervous system is indicated by a positive outcome...

    Incorrect

    • Which area of the central nervous system is indicated by a positive outcome in the finger-to-nose test?

      Your Answer:

      Correct Answer: Cerebellum

      Explanation:

      The finger-nose test requires the patient to touch their nose and then the examiner’s finger consecutively. If the patient is unable to perform this task, it indicates motor dysmetria, which is a lack of coordination and may indicate a cerebellar injury.

      Cerebellar Dysfunction: Symptoms and Signs

      Cerebellar dysfunction is a condition that affects the cerebellum, a part of the brain responsible for coordinating movement and balance. The symptoms and signs of cerebellar dysfunction include ataxia, intention tremor, nystagmus, broad-based gait, slurred speech, dysdiadochokinesis, and dysmetria (lack of finger-nose coordination).

      Ataxia refers to the lack of coordination of voluntary movements, resulting in unsteady gait, difficulty with balance, and clumsiness. Intention tremor is a type of tremor that occurs during voluntary movements, such as reaching for an object. Nystagmus is an involuntary movement of the eyes, characterized by rapid, jerky movements.

      Broad-based gait refers to a wide stance while walking, which is often seen in individuals with cerebellar dysfunction. Slurred speech, also known as dysarthria, is a common symptom of cerebellar dysfunction, which affects the ability to articulate words clearly. Dysdiadochokinesis is the inability to perform rapid alternating movements, such as tapping the fingers on the palm of the hand.

      Dysmetria refers to the inability to accurately judge the distance and direction of movements, resulting in errors in reaching for objects of touching the nose with the finger. These symptoms and signs of cerebellar dysfunction can be caused by a variety of conditions, including stroke, multiple sclerosis, and alcoholism. Treatment depends on the underlying cause and may include medications, physical therapy, and surgery.

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      • Neurosciences
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  • Question 58 - What condition is identified by the combination of Parkinsonism, cerebellar ataxia, and autonomic...

    Incorrect

    • What condition is identified by the combination of Parkinsonism, cerebellar ataxia, and autonomic failure?

      Your Answer:

      Correct Answer: Multisystem atrophy

      Explanation:

      Multisystem Atrophy: A Parkinson Plus Syndrome

      Multisystem atrophy is a type of Parkinson plus syndrome that is characterized by three main features: Parkinsonism, autonomic failure, and cerebellar ataxia. It can present in three different ways, including Shy-Drager Syndrome, Striatonigral degeneration, and Olivopontocerebellar atrophy, each with varying degrees of the three main features.

      Macroscopic features of multisystem atrophy include pallor of the substantia nigra, greenish discoloration and atrophy of the putamen, and cerebellar atrophy. Microscopic features include the presence of Papp-Lantos bodies, which are alpha-synuclein inclusions found in oligodendrocytes in the substantia nigra, cerebellum, and basal ganglia.

      Overall, multisystem atrophy is a complex and debilitating condition that affects multiple systems in the body, leading to a range of symptoms and challenges for patients and their caregivers.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 59 - Which symptom is most commonly associated with occlusion of the posterior cerebral artery?...

    Incorrect

    • Which symptom is most commonly associated with occlusion of the posterior cerebral artery?

      Your Answer:

      Correct Answer: Contralateral homonymous hemianopia with macular sparing

      Explanation:

      Brain Blood Supply and Consequences of Occlusion

      The brain receives blood supply from the internal carotid and vertebral arteries, which form the circle of Willis. The circle of Willis acts as a shunt system in case of vessel damage. The three main vessels arising from the circle are the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA). Occlusion of these vessels can result in various neurological deficits. ACA occlusion may cause hemiparesis of the contralateral foot and leg, sensory loss, and frontal signs. MCA occlusion is the most common and can lead to hemiparesis, dysphasia/aphasia, neglect, and visual field defects. PCA occlusion may cause alexia, loss of sensation, hemianopia, prosopagnosia, and cranial nerve defects. It is important to recognize these consequences to provide appropriate treatment.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 60 - What is a distinguishing characteristic of normal pressure hydrocephalus? ...

    Incorrect

    • What is a distinguishing characteristic of normal pressure hydrocephalus?

      Your Answer:

      Correct Answer: Incontinence

      Explanation:

      Headache, nausea, vomiting, papilledema, and ocular palsies are symptoms of increased intracranial pressure, which are not typically present in cases of normal pressure hydrocephalus.

      Normal Pressure Hydrocephalus

      Normal pressure hydrocephalus is a type of chronic communicating hydrocephalus, which occurs due to the impaired reabsorption of cerebrospinal fluid (CSF) by the arachnoid villi. Although the CSF pressure is typically high, it remains within the normal range, and therefore, it does not cause symptoms of high intracranial pressure (ICP) such as headache and nausea. Instead, patients with normal pressure hydrocephalus usually present with a classic triad of symptoms, including incontinence, gait ataxia, and dementia, which is often referred to as wet, wobbly, and wacky. Unfortunately, this condition is often misdiagnosed as Parkinson’s of Alzheimer’s disease.

      The classic triad of normal pressure hydrocephalus, also known as Hakim’s triad, includes gait instability, urinary incontinence, and dementia. On the other hand, non-communicating hydrocephalus results from the obstruction of CSF flow in the third of fourth ventricle, which causes symptoms of raised intracranial pressure, such as headache, vomiting, hypertension, bradycardia, altered consciousness, and papilledema.

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      • Neurosciences
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  • Question 61 - A 50-year-old individual has experienced a stroke resulting in aphasia, hemiplegia, and sensory...

    Incorrect

    • A 50-year-old individual has experienced a stroke resulting in aphasia, hemiplegia, and sensory impairment. What is the most probable area of the brain that has been affected?

      Your Answer:

      Correct Answer: Dominant middle cerebral artery

      Explanation:

      The middle cerebral artery is the most frequent location for cerebral infarction, resulting in contralateral paralysis and sensory loss. If the dominant hemisphere is affected, language impairment such as Broca’s of Wernicke’s aphasia may occur. Bilateral anterior cerebellar artery blockage is uncommon but can lead to akinetic mutism, which is characterized by a loss of speech and movement. Non-dominant middle cerebral artery blockage can cause contralateral neglect, as well as motor and sensory dysfunction, but language is typically unaffected. The occlusion of the posterior inferior cerebellar artery can result in lateral medullary syndrome, also known as Wallenberg syndrome, which is characterized by crossed contralateral and trunk sensory deficits and ipsilateral sensory deficits affecting the face and cranial nerves. Emboli in the ophthalmic artery can cause temporary vision loss, also known as amaurosis fugax, which is more commonly caused by emboli originating in the carotid artery.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 62 - From which embryonic structure does the thalamus originate? ...

    Incorrect

    • From which embryonic structure does the thalamus originate?

      Your Answer:

      Correct Answer: Diencephalon

      Explanation:

      Neurodevelopment: Understanding Brain Development

      The development of the central nervous system begins with the neuroectoderm, a specialized region of ectoderm. The embryonic brain is divided into three areas: the forebrain (prosencephalon), midbrain (mesencephalon), and hindbrain (rhombencephalon). The prosencephalon further divides into the telencephalon and diencephalon, while the hindbrain subdivides into the metencephalon and myelencephalon.

      The telencephalon, of cerebrum, consists of the cerebral cortex, underlying white matter, and the basal ganglia. The diencephalon includes the prethalamus, thalamus, hypothalamus, subthalamus, epithalamus, and pretectum. The mesencephalon comprises the tectum, tegmentum, ventricular mesocoelia, cerebral peduncles, and several nuclei and fasciculi.

      The rhombencephalon includes the medulla, pons, and cerebellum, which can be subdivided into a variable number of transversal swellings called rhombomeres. In humans, eight rhombomeres can be distinguished, from caudal to rostral: Rh7-Rh1 and the isthmus. Rhombomeres Rh7-Rh4 form the myelencephalon, while Rh3-Rh1 form the metencephalon.

      Understanding neurodevelopment is crucial in comprehending brain development and its complexities. By studying the different areas of the embryonic brain, we can gain insight into the formation of the central nervous system and its functions.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 63 - What is the accurate statement about night terrors in children? ...

    Incorrect

    • What is the accurate statement about night terrors in children?

      Your Answer:

      Correct Answer: Violent behaviour has been reported

      Explanation:

      Night terrors typically occur during deep sleep in stage 4. Upon waking, there is no memory of the experience. These episodes can be considered a dissociative state and may involve automatic behaviors. In some cases, violent behavior may occur during night terrors, but the individual cannot be held accountable for their actions. Family history is not a common factor in the occurrence of night terrors.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 64 - What is a true statement about sigma waves in relation to EEG? ...

    Incorrect

    • What is a true statement about sigma waves in relation to EEG?

      Your Answer:

      Correct Answer: They are absent in familial fatal insomnia

      Explanation:

      Sigma waves are typically observed during stage 2 sleep and are considered a normal occurrence during sleep. They usually follow muscle twitches and are believed to help maintain a peaceful state during sleep. These waves are produced in the reticular nucleus of the thalamus and arise from the interplay between the thalamus and the cortex. However, in familial fatal insomnia (a prion disease), the absence of sigma waves is a characteristic feature.

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 65 - Which of the following conditions is characterized by an increase in the size...

    Incorrect

    • Which of the following conditions is characterized by an increase in the size of the ventricles on structural neuroimaging over time?

      Your Answer:

      Correct Answer: Alzheimer's dementia

      Explanation:

      Neuroimaging studies have shown that Alzheimer’s dementia is linked to a gradual increase in ventricular size, while schizophrenia is associated with non-progressive enlargement of the lateral and third ventricles. Although some studies have reported increased ventricular size in individuals with affective disorders, the findings are not consistent. Additionally, individuals with antisocial personality disorder may have reduced prefrontal gray matter volume.

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      • Neurosciences
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  • Question 66 - A senior citizen visits your clinic and reports experiencing difficulty in seeing more...

    Incorrect

    • A senior citizen visits your clinic and reports experiencing difficulty in seeing more than one object at a time. As a result, they have been colliding with objects while moving around. What condition do you suspect?

      Your Answer:

      Correct Answer: Bilateral parieto occipital lobe dysfunction

      Explanation:

      The observed symptoms in the patient are indicative of simultanagnosia, a condition that arises due to dysfunction in the parieto occipital lobes on both sides of the brain.

      Parietal Lobe Dysfunction: Types and Symptoms

      The parietal lobe is a part of the brain that plays a crucial role in processing sensory information and integrating it with other cognitive functions. Dysfunction in this area can lead to various symptoms, depending on the location and extent of the damage.

      Dominant parietal lobe dysfunction, often caused by a stroke, can result in Gerstmann’s syndrome, which includes finger agnosia, dyscalculia, dysgraphia, and right-left disorientation. Non-dominant parietal lobe dysfunction, on the other hand, can cause anosognosia, dressing apraxia, spatial neglect, and constructional apraxia.

      Bilateral damage to the parieto-occipital lobes, a rare condition, can lead to Balint’s syndrome, which is characterized by oculomotor apraxia, optic ataxia, and simultanagnosia. These symptoms can affect a person’s ability to shift gaze, interact with objects, and perceive multiple objects at once.

      In summary, parietal lobe dysfunction can manifest in various ways, and understanding the specific symptoms can help diagnose and treat the underlying condition.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 67 - What is the most probable outcome of damage to Broca's area? ...

    Incorrect

    • What is the most probable outcome of damage to Broca's area?

      Your Answer:

      Correct Answer: Non-fluent aphasia

      Explanation:

      Broca’s aphasia is also known as non-fluent aphasia, while Wernicke’s aphasia is referred to as fluent aphasia.

      Broca’s and Wernicke’s are two types of expressive dysphasia, which is characterized by difficulty producing speech despite intact comprehension. Dysarthria is a type of expressive dysphasia caused by damage to the speech production apparatus, while Broca’s aphasia is caused by damage to the area of the brain responsible for speech production, specifically Broca’s area located in Brodmann areas 44 and 45. On the other hand, Wernicke’s aphasia is a type of receptive of fluent aphasia caused by damage to the comprehension of speech, while the actual production of speech remains normal. Wernicke’s area is located in the posterior part of the superior temporal gyrus in the dominant hemisphere, within Brodmann area 22.

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      • Neurosciences
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  • Question 68 - What is a true statement about metabotropic receptors? ...

    Incorrect

    • What is a true statement about metabotropic receptors?

      Your Answer:

      Correct Answer: Their effects tend to be more diffuse than those of ionotropic receptors

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 69 - What is the role of the Golgi apparatus in a neuron? ...

    Incorrect

    • What is the role of the Golgi apparatus in a neuron?

      Your Answer:

      Correct Answer: Packaging of macromolecules

      Explanation:

      Melanin

      Melanin is a pigment found in various parts of the body, including the skin, hair, and eyes. It is produced by specialized cells called melanocytes, which are located in the skin’s basal layer. The function of melanin in the body is not fully understood, but it is thought to play a role in protecting the skin from the harmful effects of ultraviolet (UV) radiation from the sun. Additionally, melanin may be a by-product of neurotransmitter synthesis, although this function is not well established. Overall, the role of melanin in the body is an area of ongoing research.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 70 - In which region of the brain is Broca's area located? ...

    Incorrect

    • In which region of the brain is Broca's area located?

      Your Answer:

      Correct Answer: Brodmann areas 44 and 45

      Explanation:

      Broca’s and Wernicke’s are two types of expressive dysphasia, which is characterized by difficulty producing speech despite intact comprehension. Dysarthria is a type of expressive dysphasia caused by damage to the speech production apparatus, while Broca’s aphasia is caused by damage to the area of the brain responsible for speech production, specifically Broca’s area located in Brodmann areas 44 and 45. On the other hand, Wernicke’s aphasia is a type of receptive of fluent aphasia caused by damage to the comprehension of speech, while the actual production of speech remains normal. Wernicke’s area is located in the posterior part of the superior temporal gyrus in the dominant hemisphere, within Brodmann area 22.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 71 - An individual's EEG shows widespread flattening with the existence of theta (θ) and...

    Incorrect

    • An individual's EEG shows widespread flattening with the existence of theta (θ) and delta (δ) waves of low amplitude. What is the most probable diagnosis based on this information?

      Your Answer:

      Correct Answer: Huntington's disease

      Explanation:

      The EEG findings for Huntington’s disease typically show a widespread decrease in activity with low amplitude theta (θ) and delta (δ) waves. In contrast, CJD is characterized by bilateral, synchronous generalised irregular spike wave complexes occurring at a rate of 1-2/second, often accompanied by myoclonic jerks. Hepatic encephalopathy is associated with widespread slowing and triphasic waves, while herpes simplex encephalitis is linked to repetitive episodic discharges and temporal lobe focal slow waves. HIV typically demonstrates diffuse slowing on EEG.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 72 - What is the breakdown product of serotonin? ...

    Incorrect

    • What is the breakdown product of serotonin?

      Your Answer:

      Correct Answer: 5-Hydroxyindoleacetic acid

      Explanation:

      Serotonin: Synthesis and Breakdown

      Serotonin, also known as 5-Hydroxytryptamine (5-HT), is synthesized in the central nervous system (CNS) in the raphe nuclei located in the brainstem, as well as in the gastrointestinal (GI) tract in enterochromaffin cells. The amino acid L-tryptophan, obtained from the diet, is used to synthesize serotonin. L-tryptophan can cross the blood-brain barrier, but serotonin cannot.

      The transformation of L-tryptophan into serotonin involves two steps. First, hydroxylation to 5-hydroxytryptophan is catalyzed by tryptophan hydroxylase. Second, decarboxylation of 5-hydroxytryptophan to serotonin (5-hydroxytryptamine) is catalyzed by L-aromatic amino acid decarboxylase.

      Serotonin is taken up from the synapse by a monoamine transporter (SERT). Substances that block this transporter include MDMA, amphetamine, cocaine, TCAs, and SSRIs. Serotonin is broken down by monoamine oxidase (MAO) and then by aldehyde dehydrogenase to 5-Hydroxyindoleacetic acid (5-HIAA).

    • This question is part of the following fields:

      • Neurosciences
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  • Question 73 - What is the most probable cause of medial temporal lobe atrophy on structural...

    Incorrect

    • What is the most probable cause of medial temporal lobe atrophy on structural neuroimaging in an elderly individual with cognitive decline?

      Your Answer:

      Correct Answer: Alzheimer's dementia

      Explanation:

      Medial temporal lobe atrophy (MTA) is prevalent in 80% to 90% of individuals diagnosed with Alzheimer’s dementia, and can also be present in other forms of dementia, albeit less frequently and severely. MTA is an early and relatively reliable indicator of Alzheimer’s disease, although it is not exclusive to this condition.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 74 - What is true about the pathology of Alzheimer's disease? ...

    Incorrect

    • What is true about the pathology of Alzheimer's disease?

      Your Answer:

      Correct Answer: Enlargement of the inferior horn of the lateral ventricle is seen

      Explanation:

      Normal ageing can exhibit both neurofibrillary tangles and senile plaques, while Alzheimer’s disease typically shows atrophy in the frontal, parietal, and medial temporal lobes.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 75 - Which cranial nerve is solely responsible for either sensory of motor functions and...

    Incorrect

    • Which cranial nerve is solely responsible for either sensory of motor functions and does not have a combination of both?

      Your Answer:

      Correct Answer: Abducens

      Explanation:

      Overview of Cranial Nerves and Their Functions

      The cranial nerves are a complex system of nerves that originate from the brain and control various functions of the head and neck. There are twelve cranial nerves, each with a specific function and origin. The following table provides a simplified overview of the cranial nerves, including their origin, skull exit, modality, and functions.

      The first cranial nerve, the olfactory nerve, originates from the telencephalon and exits through the cribriform plate. It is a sensory nerve that controls the sense of smell. The second cranial nerve, the optic nerve, originates from the diencephalon and exits through the optic foramen. It is a sensory nerve that controls vision.

      The third cranial nerve, the oculomotor nerve, originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement, pupillary constriction, and lens accommodation. The fourth cranial nerve, the trochlear nerve, also originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement.

      The fifth cranial nerve, the trigeminal nerve, originates from the pons and exits through different foramina depending on the division. It is a mixed nerve that controls chewing and sensation of the anterior 2/3 of the scalp. It also tenses the tympanic membrane to dampen loud noises.

      The sixth cranial nerve, the abducens nerve, originates from the pons and exits through the superior orbital fissure. It is a motor nerve that controls eye movement. The seventh cranial nerve, the facial nerve, also originates from the pons and exits through the internal auditory canal. It is a mixed nerve that controls facial expression, taste of the anterior 2/3 of the tongue, and tension on the stapes to dampen loud noises.

      The eighth cranial nerve, the vestibulocochlear nerve, originates from the pons and exits through the internal auditory canal. It is a sensory nerve that controls hearing. The ninth cranial nerve, the glossopharyngeal nerve, originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls taste of the posterior 1/3 of the tongue, elevation of the larynx and pharynx, and swallowing.

      The tenth cranial nerve, the vagus nerve, also originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls swallowing, voice production, and parasympathetic supply to nearly all thoracic and abdominal viscera. The eleventh cranial nerve, the accessory nerve, originates from the medulla and exits through the jugular foramen. It is a motor nerve that controls shoulder shrugging and head turning.

      The twelfth cranial nerve, the hypoglossal nerve, originates from the medulla and exits through the hypoglossal canal. It is a motor nerve that controls tongue movement. Overall, the cranial nerves play a crucial role in controlling various functions of the head and neck, and any damage of dysfunction can have significant consequences.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 76 - In which area of the skull is the structure located in the anterior...

    Incorrect

    • In which area of the skull is the structure located in the anterior cranial fossa?

      Your Answer:

      Correct Answer: Cribriform plate

      Explanation:

      The ethmoid bone contains the cribriform plate, which acts as a barrier between the nasal cavity and the brain.

      Cranial Fossae and Foramina

      The cranium is divided into three regions known as fossae, each housing different cranial lobes. The anterior cranial fossa contains the frontal lobes and includes the frontal and ethmoid bones, as well as the lesser wing of the sphenoid. The middle cranial fossa contains the temporal lobes and includes the greater wing of the sphenoid, sella turcica, and most of the temporal bones. The posterior cranial fossa contains the occipital lobes, cerebellum, and medulla and includes the occipital bone.

      There are several foramina in the skull that allow for the passage of various structures. The most important foramina likely to appear in exams are listed below:

      – Foramen spinosum: located in the middle fossa and allows for the passage of the middle meningeal artery.
      – Foramen ovale: located in the middle fossa and allows for the passage of the mandibular division of the trigeminal nerve.
      – Foramen lacerum: located in the middle fossa and allows for the passage of the small meningeal branches of the ascending pharyngeal artery and emissary veins from the cavernous sinus.
      – Foramen magnum: located in the posterior fossa and allows for the passage of the spinal cord.
      – Jugular foramen: located in the posterior fossa and allows for the passage of cranial nerves IX, X, and XI.

      Understanding the location and function of these foramina is essential for medical professionals, as they play a crucial role in the diagnosis and treatment of various neurological conditions.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 77 - Through which route does the caudate nucleus obtain its blood supply? ...

    Incorrect

    • Through which route does the caudate nucleus obtain its blood supply?

      Your Answer:

      Correct Answer: Anterior and middle cerebral arteries

      Explanation:

      The blood supply to the caudate nucleus primarily comes from the deep penetrators of the anterior and middle cerebral arteries. The effects of caudate infarcts can differ depending on the study, but typically include behavioral symptoms such as abulia and agitation, loss of executive function, and motor weakness.

      Brain Blood Supply and Consequences of Occlusion

      The brain receives blood supply from the internal carotid and vertebral arteries, which form the circle of Willis. The circle of Willis acts as a shunt system in case of vessel damage. The three main vessels arising from the circle are the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA). Occlusion of these vessels can result in various neurological deficits. ACA occlusion may cause hemiparesis of the contralateral foot and leg, sensory loss, and frontal signs. MCA occlusion is the most common and can lead to hemiparesis, dysphasia/aphasia, neglect, and visual field defects. PCA occlusion may cause alexia, loss of sensation, hemianopia, prosopagnosia, and cranial nerve defects. It is important to recognize these consequences to provide appropriate treatment.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 78 - What is a correct statement about the blood brain barrier? ...

    Incorrect

    • What is a correct statement about the blood brain barrier?

      Your Answer:

      Correct Answer: Nasally administered drugs can bypass the blood brain barrier

      Explanation:

      Understanding the Blood Brain Barrier

      The blood brain barrier (BBB) is a crucial component of the brain’s defense system against harmful chemicals and ion imbalances. It is a semi-permeable membrane formed by tight junctions of endothelial cells in the brain’s capillaries, which separates the blood from the cerebrospinal fluid. However, certain areas of the BBB, known as circumventricular organs, are fenestrated to allow neurosecretory products to enter the blood.

      When it comes to MRCPsych questions, the focus is on the following aspects of the BBB: the tight junctions between endothelial cells, the ease with which lipid-soluble molecules pass through compared to water-soluble ones, the difficulty large and highly charged molecules face in passing through, the increased permeability of the BBB during inflammation, and the theoretical ability of nasally administered drugs to bypass the BBB.

      It is important to remember the specific circumventricular organs where the BBB is fenestrated, including the posterior pituitary and the area postrema. Understanding the BBB’s function and characteristics is essential for medical professionals to diagnose and treat neurological disorders effectively.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 79 - What substance precedes the production of serotonin? ...

    Incorrect

    • What substance precedes the production of serotonin?

      Your Answer:

      Correct Answer: 5-hydroxytryptophan

      Explanation:

      Serotonin: Synthesis and Breakdown

      Serotonin, also known as 5-Hydroxytryptamine (5-HT), is synthesized in the central nervous system (CNS) in the raphe nuclei located in the brainstem, as well as in the gastrointestinal (GI) tract in enterochromaffin cells. The amino acid L-tryptophan, obtained from the diet, is used to synthesize serotonin. L-tryptophan can cross the blood-brain barrier, but serotonin cannot.

      The transformation of L-tryptophan into serotonin involves two steps. First, hydroxylation to 5-hydroxytryptophan is catalyzed by tryptophan hydroxylase. Second, decarboxylation of 5-hydroxytryptophan to serotonin (5-hydroxytryptamine) is catalyzed by L-aromatic amino acid decarboxylase.

      Serotonin is taken up from the synapse by a monoamine transporter (SERT). Substances that block this transporter include MDMA, amphetamine, cocaine, TCAs, and SSRIs. Serotonin is broken down by monoamine oxidase (MAO) and then by aldehyde dehydrogenase to 5-Hydroxyindoleacetic acid (5-HIAA).

    • This question is part of the following fields:

      • Neurosciences
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  • Question 80 - Which neuroimaging technique that maps cortical activation uses the non-invasive BOLD method? ...

    Incorrect

    • Which neuroimaging technique that maps cortical activation uses the non-invasive BOLD method?

      Your Answer:

      Correct Answer: Functional MRI (fMRI)

      Explanation:

      The BOLD technique is used by fMRI to non-invasively map cortical activation, while PET and SPECT require the administration of a radioactive isotope and are invasive. Although all three magnetic imaging techniques are non-invasive, fMRI stands out for its use of the BOLD technique.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 81 - From which substance is melatonin produced? ...

    Incorrect

    • From which substance is melatonin produced?

      Your Answer:

      Correct Answer: Serotonin

      Explanation:

      Melatonin: The Hormone of Darkness

      Melatonin is a hormone that is produced in the pineal gland from serotonin. This hormone is known to be released in higher amounts during the night, especially in dark environments. Melatonin plays a crucial role in regulating the sleep-wake cycle and is often referred to as the hormone of darkness.

      The production of melatonin is influenced by the amount of light that enters the eyes. When it is dark, the pineal gland releases more melatonin, which helps to promote sleep. On the other hand, when it is light, the production of melatonin is suppressed, which helps to keep us awake and alert.

      Melatonin is also known to have antioxidant properties and may help to protect the body against oxidative stress. It has been suggested that melatonin may have a role in the prevention of certain diseases, such as cancer and neurodegenerative disorders.

      Overall, melatonin is an important hormone that plays a crucial role in regulating our sleep-wake cycle and may have other health benefits as well.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 82 - What does the presence of a fenestrated cavum septum pellucidum indicate? ...

    Incorrect

    • What does the presence of a fenestrated cavum septum pellucidum indicate?

      Your Answer:

      Correct Answer: Punch drunk syndrome

      Explanation:

      A fenestrated cavum septum pellucidum is linked to dementia pugilistica.

      Dementia Pugilistica: A Neurodegenerative Condition Resulting from Neurotrauma

      Dementia pugilistica, also known as chronic traumatic encephalopathy (CTE), is a neurodegenerative condition that results from neurotrauma. It is commonly seen in boxers and NFL players, but can also occur in anyone with neurotrauma. The condition is characterized by symptoms such as gait ataxia, slurred speech, impaired hearing, tremors, disequilibrium, neurobehavioral disturbances, and progressive cognitive decline.

      Most cases of dementia pugilistica present with early onset cognitive deficits, and behavioral signs exhibited by patients include aggression, suspiciousness, paranoia, childishness, hypersexuality, depression, and restlessness. The progression of the condition leads to more prominent behavioral symptoms such as difficulty with impulse control, irritability, inappropriateness, and explosive outbursts of aggression.

      Neuropathological abnormalities have been identified in CTE, with the most unique feature being the abnormal accumulation of tau in neurons and glia in an irregular, focal, perivascular distribution and at the depths of cortical sulci. Abnormalities of the septum pellucidum, such as cavum and fenestration, are also a common feature.

      While the condition has become increasingly rare due to the progressive improvement in sports safety, it is important to recognize the potential long-term consequences of repeated head injuries and take steps to prevent them.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 83 - Where are Lewy bodies commonly located within the basal ganglia in individuals with...

    Incorrect

    • Where are Lewy bodies commonly located within the basal ganglia in individuals with Parkinson's disease?

      Your Answer:

      Correct Answer: The pars compacta

      Explanation:

      The midbrain contains a section called the pars compacta, which is made up of neurons that produce dopamine and is situated next to the pars reticulata. Parkinson’s disease is identified by the loss of these dopamine-producing neurons in this area.

      Parkinson’s Disease Pathology

      Parkinson’s disease is a neurodegenerative disorder that affects the central nervous system. The pathology of Parkinson’s disease is very similar to that of Lewy body dementia. The macroscopic features of Parkinson’s disease include pallor of the substantia nigra (midbrain) and locus coeruleus (pons). The microscopic changes include the presence of Lewy bodies, which are intracellular aggregates of alpha-synuclein. Additionally, there is a loss of dopaminergic cells from the substantia nigra pars compacta. These changes contribute to the motor symptoms of Parkinson’s disease, such as tremors, rigidity, and bradykinesia. Understanding the pathology of Parkinson’s disease is crucial for developing effective treatments and improving the quality of life for those affected by this condition.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 84 - Which of the following eosinophilic inclusion bodies are observed as a neuropathological discovery...

    Incorrect

    • Which of the following eosinophilic inclusion bodies are observed as a neuropathological discovery in individuals with Alzheimer's disease?

      Your Answer:

      Correct Answer: Hirano bodies

      Explanation:

      Hirano bodies, Pick bodies, Lewy bodies, Negri bodies, and Barr bodies are all types of inclusion bodies that can be seen in various cells. Hirano bodies are rod-shaped structures found in the cytoplasm of neurons, composed of actin and other proteins. They are commonly seen in the hippocampus, along with granulovacuolar degeneration, which may represent lysosomal accumulations within neuronal cytoplasm. The clinical significance of these microscopic features is not yet fully understood. Pick bodies are masses of cytoskeletal elements seen in Pick’s disease, while Lewy bodies are abnormal protein aggregates that develop in nerve cells in Lewy body disease. Negri bodies are inclusion bodies seen in rabies, and Barr bodies are inactive X chromosomes in a female somatic cell.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 85 - What EEG finding has consistently been associated with the use of clozapine? ...

    Incorrect

    • What EEG finding has consistently been associated with the use of clozapine?

      Your Answer:

      Correct Answer: Decreased alpha, increased theta, increased delta

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 86 - In what circumstances are neurofibrillary tangles less commonly observed? ...

    Incorrect

    • In what circumstances are neurofibrillary tangles less commonly observed?

      Your Answer:

      Correct Answer: Vascular dementia

      Explanation:

      Tauopathies exhibit tangles, but vascular dementia is not classified as one.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 87 - What brain structures are responsible for regulating breathing and heart rate? ...

    Incorrect

    • What brain structures are responsible for regulating breathing and heart rate?

      Your Answer:

      Correct Answer: Medulla

      Explanation:

      The medulla governs the rhythm of the heart and respiration. The amygdala regulates emotional reactions and the ability to perceive the emotions of others. The midbrain is linked to vision, hearing, motor coordination, sleep patterns, alertness, and temperature regulation. The cerebellum manages voluntary movement and balance. The thalamus transmits sensory and motor signals to the cerebral cortex.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 88 - What is a true statement about senile plaques? ...

    Incorrect

    • What is a true statement about senile plaques?

      Your Answer:

      Correct Answer: They consist of beta amyloid

      Explanation:

      Senile plaques are formed by beta amyloid proteins that have folded abnormally and are found in the extracellular space of the grey matter. While they are present in smaller quantities during normal aging, they are insoluble. These plaques are created due to the improper cleavage of Amyloid Precursor Protein (APP), a transmembrane protein whose function is not fully understood.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 89 - What is the most common symptom associated with primary progressive aphasia? ...

    Incorrect

    • What is the most common symptom associated with primary progressive aphasia?

      Your Answer:

      Correct Answer: Atrophy of left perisylvian region

      Explanation:

      Primary progressive aphasia is a specific type of frontotemporal dementia that is characterized by the degeneration of the left perisylvian region. Frontotemporal dementia can be divided into two subtypes: behavioral, which involves atrophy of the frontal region, and language, which includes primary progressive aphasia and semantic dementia. The language subtypes of frontotemporal dementia typically exhibit more severe atrophy on the left side of the brain. Semantic dementia is characterized by greater atrophy in the anterior temporal lobe compared to the posterior temporal lobe. In contrast, Alzheimer’s dementia is associated with bilateral hippocampal atrophy, while vascular dementia is characterized by diffuse white matter lesions.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 90 - From which amino acids are the catecholamines derived? ...

    Incorrect

    • From which amino acids are the catecholamines derived?

      Your Answer:

      Correct Answer: Tyrosine

      Explanation:

      Catecholamines are a group of chemical compounds that have a distinct structure consisting of a benzene ring with two hydroxyl groups, an intermediate ethyl chain, and a terminal amine group. These compounds play an important role in the body and are involved in various physiological processes. The three main catecholamines found in the body are dopamine, adrenaline, and noradrenaline. All of these compounds are derived from the amino acid tyrosine. Overall, catecholamines are essential for maintaining proper bodily functions and are involved in a wide range of physiological processes.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 91 - Which substance is 5-HIAA a metabolite of? ...

    Incorrect

    • Which substance is 5-HIAA a metabolite of?

      Your Answer:

      Correct Answer: Serotonin

      Explanation:

      The Significance of 5-HIAA in Depression and Aggression

      During the 1980s, there was a brief period of interest in 5-hydroxyindoleacetic acid (5-HIAA), a serotonin metabolite. Studies found that up to a third of people with depression had low concentrations of 5-HIAA in their cerebrospinal fluid (CSF), while very few normal controls did. This suggests that 5-HIAA may play a role in depression.

      Furthermore, individuals with low CSF levels of 5-HIAA have been found to respond less effectively to antidepressants and are more likely to commit suicide. This finding has been replicated in multiple studies, indicating the significance of 5-HIAA in depression.

      Low levels of 5-HIAA are also associated with increased levels of aggression. This suggests that 5-HIAA may play a role in regulating aggressive behavior. Overall, the research on 5-HIAA highlights its potential importance in understanding and treating depression and aggression.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 92 - In dementia pugilistica, which structure is commonly found to be abnormal? ...

    Incorrect

    • In dementia pugilistica, which structure is commonly found to be abnormal?

      Your Answer:

      Correct Answer: Septum pellucidum

      Explanation:

      A fenestrated cavum septum pellucidum is linked to dementia pugilistica.

      Dementia Pugilistica: A Neurodegenerative Condition Resulting from Neurotrauma

      Dementia pugilistica, also known as chronic traumatic encephalopathy (CTE), is a neurodegenerative condition that results from neurotrauma. It is commonly seen in boxers and NFL players, but can also occur in anyone with neurotrauma. The condition is characterized by symptoms such as gait ataxia, slurred speech, impaired hearing, tremors, disequilibrium, neurobehavioral disturbances, and progressive cognitive decline.

      Most cases of dementia pugilistica present with early onset cognitive deficits, and behavioral signs exhibited by patients include aggression, suspiciousness, paranoia, childishness, hypersexuality, depression, and restlessness. The progression of the condition leads to more prominent behavioral symptoms such as difficulty with impulse control, irritability, inappropriateness, and explosive outbursts of aggression.

      Neuropathological abnormalities have been identified in CTE, with the most unique feature being the abnormal accumulation of tau in neurons and glia in an irregular, focal, perivascular distribution and at the depths of cortical sulci. Abnormalities of the septum pellucidum, such as cavum and fenestration, are also a common feature.

      While the condition has become increasingly rare due to the progressive improvement in sports safety, it is important to recognize the potential long-term consequences of repeated head injuries and take steps to prevent them.

    • This question is part of the following fields:

      • Neurosciences
      0
      Seconds
  • Question 93 - Which statement accurately describes neurofibrillary tangles? ...

    Incorrect

    • Which statement accurately describes neurofibrillary tangles?

      Your Answer:

      Correct Answer: They are also seen in dementia pugilistica

      Explanation:

      Amyloid protein is the primary component of amyloid plaques, although they are most commonly linked to Alzheimer’s disease.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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      Seconds
  • Question 94 - Which statement about multiple sclerosis is incorrect? ...

    Incorrect

    • Which statement about multiple sclerosis is incorrect?

      Your Answer:

      Correct Answer: It is more common in males

      Explanation:

      The statement MS is more common in females is actually correct.

      Multiple Sclerosis: An Overview

      Multiple sclerosis is a neurological disorder that is classified into three categories: primary progressive, relapsing-remitting, and secondary progressive. Primary progressive multiple sclerosis affects 5-10% of patients and is characterized by a steady progression with no remissions. Relapsing-remitting multiple sclerosis affects 20-30% of patients and presents with a relapsing-remitting course but does not lead to serious disability. Secondary progressive multiple sclerosis affects 60% of patients and initially presents with a relapsing-remitting course but is then followed by a phase of progressive deterioration.

      The disorder typically begins between the ages of 20 and 40 and is characterized by multiple demyelinating lesions that have a preference for the optic nerves, cerebellum, brainstem, and spinal cord. Patients with multiple sclerosis present with a variety of neurological signs that reflect the presence and distribution of plaques. Ocular features of multiple sclerosis include optic neuritis, internuclear ophthalmoplegia, and ocular motor cranial neuropathy.

      Multiple sclerosis is more common in women than in men and is seen with increasing frequency as the distance from the equator increases. It is believed to be caused by a combination of genetic and environmental factors, with monozygotic concordance at 25%. Overall, multiple sclerosis is a predominantly white matter disease that can have a significant impact on a patient’s quality of life.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 95 - From where does the nerve that originates in the medulla oblongata come? ...

    Incorrect

    • From where does the nerve that originates in the medulla oblongata come?

      Your Answer:

      Correct Answer: Vagus

      Explanation:

      Overview of Cranial Nerves and Their Functions

      The cranial nerves are a complex system of nerves that originate from the brain and control various functions of the head and neck. There are twelve cranial nerves, each with a specific function and origin. The following table provides a simplified overview of the cranial nerves, including their origin, skull exit, modality, and functions.

      The first cranial nerve, the olfactory nerve, originates from the telencephalon and exits through the cribriform plate. It is a sensory nerve that controls the sense of smell. The second cranial nerve, the optic nerve, originates from the diencephalon and exits through the optic foramen. It is a sensory nerve that controls vision.

      The third cranial nerve, the oculomotor nerve, originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement, pupillary constriction, and lens accommodation. The fourth cranial nerve, the trochlear nerve, also originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement.

      The fifth cranial nerve, the trigeminal nerve, originates from the pons and exits through different foramina depending on the division. It is a mixed nerve that controls chewing and sensation of the anterior 2/3 of the scalp. It also tenses the tympanic membrane to dampen loud noises.

      The sixth cranial nerve, the abducens nerve, originates from the pons and exits through the superior orbital fissure. It is a motor nerve that controls eye movement. The seventh cranial nerve, the facial nerve, also originates from the pons and exits through the internal auditory canal. It is a mixed nerve that controls facial expression, taste of the anterior 2/3 of the tongue, and tension on the stapes to dampen loud noises.

      The eighth cranial nerve, the vestibulocochlear nerve, originates from the pons and exits through the internal auditory canal. It is a sensory nerve that controls hearing. The ninth cranial nerve, the glossopharyngeal nerve, originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls taste of the posterior 1/3 of the tongue, elevation of the larynx and pharynx, and swallowing.

      The tenth cranial nerve, the vagus nerve, also originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls swallowing, voice production, and parasympathetic supply to nearly all thoracic and abdominal viscera. The eleventh cranial nerve, the accessory nerve, originates from the medulla and exits through the jugular foramen. It is a motor nerve that controls shoulder shrugging and head turning.

      The twelfth cranial nerve, the hypoglossal nerve, originates from the medulla and exits through the hypoglossal canal. It is a motor nerve that controls tongue movement. Overall, the cranial nerves play a crucial role in controlling various functions of the head and neck, and any damage of dysfunction can have significant consequences.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 96 - What brain region has been identified as a target for deep brain stimulation...

    Incorrect

    • What brain region has been identified as a target for deep brain stimulation (DBS) in individuals with treatment-resistant depression?

      Your Answer:

      Correct Answer: Nucleus accumbens

      Explanation:

      Deep brain stimulation (DBS) for treatment resistant depression targets specific brain regions based on their known involvement in pleasure, reward, and mood regulation. The nucleus accumbens is targeted due to its role in pleasure and reward processing. The inferior thalamic peduncle is targeted based on PET studies showing hyperactivity in depression. The lateral habenula is chosen due to observed hypermetabolism in depressed patients. The subgenual cingulate gyrus is targeted due to its hyperactivity in depression. The ventral capsule/ventral striatum is chosen based on its association with improved mood and reduced depressive symptoms following ablation treatments for OCD and depression.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 97 - Which factor is most closely linked to the development of dementia in individuals...

    Incorrect

    • Which factor is most closely linked to the development of dementia in individuals with HIV?

      Your Answer:

      Correct Answer: Monocyte infiltration and microglial activation

      Explanation:

      The strongest association with HIV dementia is the infiltration of monocytes and activation of microglia in the brain. While the presence of HIV encephalopathy is somewhat linked to HIV associated dementia, the extent of monocyte infiltration and microglial activation is the best indicator of AIDS dementia. Microglia can cause damage to neurons by releasing oxidative radicals, nitric oxide, and cytokines. The correlation between viral load and HAD is not significant. Astrocytes have limited susceptibility to HIV infection, and neuronal infection is rare and unlikely to have a significant impact on HIV-related CNS disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 98 - An agitated elderly patient requires restraint. Following the restraint, your examination of the...

    Incorrect

    • An agitated elderly patient requires restraint. Following the restraint, your examination of the patient reveals an inability to shrug the shoulders. Which nerve is most likely to have been damaged?

      Accessory

      91%

      Hypoglossal

      4%

      Abducent

      4%

      Oculomotor

      0%

      Glossopharyngeal

      1%

      This elderly patient has most likely suffered a traumatic injury to the accessory nerve.

      Your Answer:

      Correct Answer: Accessory

      Explanation:

      It is probable that this individual has experienced a traumatic injury affecting the accessory nerve.

      Overview of Cranial Nerves and Their Functions

      The cranial nerves are a complex system of nerves that originate from the brain and control various functions of the head and neck. There are twelve cranial nerves, each with a specific function and origin. The following table provides a simplified overview of the cranial nerves, including their origin, skull exit, modality, and functions.

      The first cranial nerve, the olfactory nerve, originates from the telencephalon and exits through the cribriform plate. It is a sensory nerve that controls the sense of smell. The second cranial nerve, the optic nerve, originates from the diencephalon and exits through the optic foramen. It is a sensory nerve that controls vision.

      The third cranial nerve, the oculomotor nerve, originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement, pupillary constriction, and lens accommodation. The fourth cranial nerve, the trochlear nerve, also originates from the midbrain and exits through the superior orbital fissure. It is a motor nerve that controls eye movement.

      The fifth cranial nerve, the trigeminal nerve, originates from the pons and exits through different foramina depending on the division. It is a mixed nerve that controls chewing and sensation of the anterior 2/3 of the scalp. It also tenses the tympanic membrane to dampen loud noises.

      The sixth cranial nerve, the abducens nerve, originates from the pons and exits through the superior orbital fissure. It is a motor nerve that controls eye movement. The seventh cranial nerve, the facial nerve, also originates from the pons and exits through the internal auditory canal. It is a mixed nerve that controls facial expression, taste of the anterior 2/3 of the tongue, and tension on the stapes to dampen loud noises.

      The eighth cranial nerve, the vestibulocochlear nerve, originates from the pons and exits through the internal auditory canal. It is a sensory nerve that controls hearing. The ninth cranial nerve, the glossopharyngeal nerve, originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls taste of the posterior 1/3 of the tongue, elevation of the larynx and pharynx, and swallowing.

      The tenth cranial nerve, the vagus nerve, also originates from the medulla and exits through the jugular foramen. It is a mixed nerve that controls swallowing, voice production, and parasympathetic supply to nearly all thoracic and abdominal viscera. The eleventh cranial nerve, the accessory nerve, originates from the medulla and exits through the jugular foramen. It is a motor nerve that controls shoulder shrugging and head turning.

      The twelfth cranial nerve, the hypoglossal nerve, originates from the medulla and exits through the hypoglossal canal. It is a motor nerve that controls tongue movement. Overall, the cranial nerves play a crucial role in controlling various functions of the head and neck, and any damage of dysfunction can have significant consequences.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 99 - What are the potential consequences of damage to the dominant cerebral hemisphere? ...

    Incorrect

    • What are the potential consequences of damage to the dominant cerebral hemisphere?

      Your Answer:

      Correct Answer: Right-left disorientation

      Explanation:

      Hemispheric Damage: Selected Deficits in Dominant and Non-Dominant Hemispheres

      Many functions are performed by both the right and left cerebral hemispheres. However, certain functions are localized, and damage to a specific hemisphere can result in deficits in specific areas. The following table outlines selected deficits seen in hemispheric damage.

      Dominant Hemisphere (usually left):
      – Aphasia: difficulty with language and communication
      – Limb apraxia: difficulty with skilled movements of limbs
      – Finger agnosia: difficulty recognizing fingers
      – Dysgraphia (aphasic): difficulty with writing and spelling
      – Dyscalculia (number alexia): difficulty with reading and understanding numbers
      – Constructional apraxia: difficulty with constructing objects of copying designs
      – Right-left disorientation: difficulty distinguishing left from right

      Non-Dominant Hemisphere (usually right):
      – Visuospatial deficits: difficulty with spatial perception and orientation
      – Impaired visual perception: difficulty with recognizing and interpreting visual information
      – Neglect: lack of awareness of one side of the body of environment
      – Dysgraphia (spatial neglect): difficulty with writing on one side of the page
      – Dyscalculia (spatial): difficulty with spatial reasoning and understanding of shapes and sizes
      – Constructional apraxia (Gestalt): difficulty with assembling parts into a whole
      – Dressing apraxia: difficulty with dressing oneself
      – Anosognosia: lack of awareness of denial of one’s own deficits of condition.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 100 - What does the following describe: A clinical manifestation that quickly appears and indicates...

    Incorrect

    • What does the following describe: A clinical manifestation that quickly appears and indicates a localized disruption in brain function, believed to be caused by a vascular issue and lasting for more than 24 hours.

      Your Answer:

      Correct Answer: Stroke

      Explanation:

      Cerebrovascular accidents (CVA), also known as strokes, are defined by the World Health Organization as a sudden onset of focal neurological symptoms lasting more than 24 hours and presumed to be of vascular origin. Strokes can be caused by either infarction of hemorrhage, with infarction being more common. Hemorrhagic strokes tend to be more severe. Intracranial hemorrhage can be primary, caused mainly by hypertension, of subarachnoid, caused by the rupture of an aneurysm of angioma. Primary intracranial hemorrhage is most common in individuals aged 60-80 and often occurs during exertion. Infarction can be caused by thrombosis of embolism, with thrombosis being more common. Atherosclerosis, often caused by hypertension, is the main cause of infarction. CT scanning is the preferred diagnostic tool during the first 48 hours after a stroke as it can distinguish between infarcts and hemorrhages. Recovery from embolism is generally quicker and more complete than from thrombosis due to the availability of collateral channels.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 101 - What is another term for 'intrinsic activity' when referring to drug/receptor interactions? ...

    Incorrect

    • What is another term for 'intrinsic activity' when referring to drug/receptor interactions?

      Your Answer:

      Correct Answer: Efficacy

      Explanation:

      Efficacy, also referred to as intrinsic activity, pertains to a drug’s capacity to produce a reaction upon binding to a receptor.

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 102 - Which of the following cannot trigger abnormal wave patterns on the EEG? ...

    Incorrect

    • Which of the following cannot trigger abnormal wave patterns on the EEG?

      Your Answer:

      Correct Answer: Cold environments

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 103 - Which structure's division results in a condition known as 'split brain'? ...

    Incorrect

    • Which structure's division results in a condition known as 'split brain'?

      Your Answer:

      Correct Answer: Corpus callosum

      Explanation:

      The Corpus Callosum and Circle of Willis: Important Structures in the Brain

      The corpus callosum is a thick bundle of fibers that connects the two cerebral hemispheres. When this structure is divided, communication between the hemispheres is disrupted, resulting in observable effects through experimental techniques. For instance, if an object is presented to the left visual field only (and therefore processed by the right visual cortex only), a subject may be unable to name the object out loud due to the speech center typically being located in the left hemisphere.

      On the other hand, the Circle of Willis is a crucial part of the cerebral circulation. If the optic chiasm is divided, it can lead to specific visual problems known as chiasmal syndrome. These structures play important roles in brain function and can have significant consequences when damaged of disrupted.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 104 - What is the condition that is identified by the presence of Papp-Lantos bodies?...

    Incorrect

    • What is the condition that is identified by the presence of Papp-Lantos bodies?

      Your Answer:

      Correct Answer: Multisystem atrophy

      Explanation:

      Multisystem Atrophy: A Parkinson Plus Syndrome

      Multisystem atrophy is a type of Parkinson plus syndrome that is characterized by three main features: Parkinsonism, autonomic failure, and cerebellar ataxia. It can present in three different ways, including Shy-Drager Syndrome, Striatonigral degeneration, and Olivopontocerebellar atrophy, each with varying degrees of the three main features.

      Macroscopic features of multisystem atrophy include pallor of the substantia nigra, greenish discoloration and atrophy of the putamen, and cerebellar atrophy. Microscopic features include the presence of Papp-Lantos bodies, which are alpha-synuclein inclusions found in oligodendrocytes in the substantia nigra, cerebellum, and basal ganglia.

      Overall, multisystem atrophy is a complex and debilitating condition that affects multiple systems in the body, leading to a range of symptoms and challenges for patients and their caregivers.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 105 - What is the accurate statement about the pathology of schizophrenia? ...

    Incorrect

    • What is the accurate statement about the pathology of schizophrenia?

      Your Answer:

      Correct Answer: Brain volume of affected individuals is often reduced

      Explanation:

      While ventricular enlargement is often observed in individuals with schizophrenia, it is not a definitive indicator of the condition as it can also be present in other disorders.

      Schizophrenia is a pathology that is characterized by a number of structural and functional brain alterations. Structural alterations include enlargement of the ventricles, reductions in total brain and gray matter volume, and regional reductions in the amygdala, parahippocampal gyrus, and temporal lobes. Antipsychotic treatment may be associated with gray matter loss over time, and even drug-naïve patients show volume reductions. Cerebral asymmetry is also reduced in affected individuals and healthy relatives. Functional alterations include diminished activation of frontal regions during cognitive tasks and increased activation of temporal regions during hallucinations. These findings suggest that schizophrenia is associated with both macroscopic and functional changes in the brain.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 106 - What is the most probable outcome of the occlusion of the main trunk...

    Incorrect

    • What is the most probable outcome of the occlusion of the main trunk of the middle cerebral artery?

      Your Answer:

      Correct Answer: Hemiparesis of the contralateral face and limbs

      Explanation:

      Brain Blood Supply and Consequences of Occlusion

      The brain receives blood supply from the internal carotid and vertebral arteries, which form the circle of Willis. The circle of Willis acts as a shunt system in case of vessel damage. The three main vessels arising from the circle are the anterior cerebral artery (ACA), middle cerebral artery (MCA), and posterior cerebral artery (PCA). Occlusion of these vessels can result in various neurological deficits. ACA occlusion may cause hemiparesis of the contralateral foot and leg, sensory loss, and frontal signs. MCA occlusion is the most common and can lead to hemiparesis, dysphasia/aphasia, neglect, and visual field defects. PCA occlusion may cause alexia, loss of sensation, hemianopia, prosopagnosia, and cranial nerve defects. It is important to recognize these consequences to provide appropriate treatment.

    • This question is part of the following fields:

      • Neurosciences
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      Seconds
  • Question 107 - Which wave pattern is considered the most abnormal during a state of wakefulness?...

    Incorrect

    • Which wave pattern is considered the most abnormal during a state of wakefulness?

      Your Answer:

      Correct Answer: Delta

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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      Seconds
  • Question 108 - Which of the following is not considered a characteristic of Klüver-Bucy syndrome? ...

    Incorrect

    • Which of the following is not considered a characteristic of Klüver-Bucy syndrome?

      Your Answer:

      Correct Answer: Visual apraxia

      Explanation:

      Kluver-Bucy Syndrome: Causes and Symptoms

      Kluver-Bucy syndrome is a neurological disorder that results from bilateral medial temporal lobe dysfunction, particularly in the amygdala. This condition is characterized by a range of symptoms, including hyperorality (a tendency to explore objects with the mouth), hypersexuality, docility, visual agnosia, and dietary changes.

      The most common causes of Kluver-Bucy syndrome include herpes, late-stage Alzheimer’s disease, frontotemporal dementia, trauma, and bilateral temporal lobe infarction. In some cases, the condition may be reversible with treatment, but in others, it may be permanent and require ongoing management. If you of someone you know is experiencing symptoms of Kluver-Bucy syndrome, it is important to seek medical attention promptly to determine the underlying cause and develop an appropriate treatment plan.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 109 - Which of the following do not describe the features of REM sleep? ...

    Incorrect

    • Which of the following do not describe the features of REM sleep?

      Your Answer:

      Correct Answer: K complexes on the EEG

      Explanation:

      During REM sleep, the EEG patterns resemble those observed during wakefulness, characterized by numerous beta-rhythms that are fast.

      Sleep Stages

      Sleep is divided into two distinct states called rapid eye movement (REM) and non-rapid eye movement (NREM). NREM is subdivided into four stages.

      Sleep stage
      Approx % of time spent in stage
      EEG findings
      Comment

      I
      5%
      Theta waves (4-7 Hz)
      The dozing off stage. Characterized by hypnic jerks: spontaneous myoclonic contractions associated with a sensation of twitching of falling.

      II
      45%
      Theta waves, K complexes and sleep spindles (short bursts of 12-14 Hz activity)
      Body enters a more subdued state including a drop in temperature, relaxed muscles, and slowed breathing and heart rate. At the same time, brain waves show a new pattern and eye movement stops.

      III
      15%
      Delta waves (0-4 Hz)
      Deepest stage of sleep (high waking threshold). The length of stage 3 decreases over the course of the night.

      IV
      15%
      Mixed, predominantly beta
      High dream activity.

      The percentage of REM sleep decreases with age.

      It takes the average person 15-20 minutes to fall asleep, this is called sleep latency (characterised by the onset of stage I sleep). Once asleep one descends through stages I-II and then III-IV (deep stages). After about 90 minutes of sleep one enters REM. The rest of the sleep comprises of cycles through the stages. As the sleep progresses the periods of REM become greater and the periods of NREM become less. During an average night’s sleep one spends 25% of the sleep in REM and 75% in NREM.

      REM sleep has certain characteristics that separate it from NREM

      Characteristics of REM sleep

      – Autonomic instability (variability in heart rate, respiratory rate, and BP)
      – Loss of muscle tone
      – Dreaming
      – Rapid eye movements
      – Penile erection

      Deafness:

      (No information provided on deafness in relation to sleep stages)

    • This question is part of the following fields:

      • Neurosciences
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  • Question 110 - The pineal gland secretes which of the following? ...

    Incorrect

    • The pineal gland secretes which of the following?

      Your Answer:

      Correct Answer: Melatonin

      Explanation:

      Melatonin: The Hormone of Darkness

      Melatonin is a hormone that is produced in the pineal gland from serotonin. This hormone is known to be released in higher amounts during the night, especially in dark environments. Melatonin plays a crucial role in regulating the sleep-wake cycle and is often referred to as the hormone of darkness.

      The production of melatonin is influenced by the amount of light that enters the eyes. When it is dark, the pineal gland releases more melatonin, which helps to promote sleep. On the other hand, when it is light, the production of melatonin is suppressed, which helps to keep us awake and alert.

      Melatonin is also known to have antioxidant properties and may help to protect the body against oxidative stress. It has been suggested that melatonin may have a role in the prevention of certain diseases, such as cancer and neurodegenerative disorders.

      Overall, melatonin is an important hormone that plays a crucial role in regulating our sleep-wake cycle and may have other health benefits as well.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 111 - What is a true statement about the neocortex? ...

    Incorrect

    • What is a true statement about the neocortex?

      Your Answer:

      Correct Answer: It contains both pyramidal and nonpyramidal cells

      Explanation:

      The Cerebral Cortex and Neocortex

      The cerebral cortex is the outermost layer of the cerebral hemispheres and is composed of three parts: the archicortex, paleocortex, and neocortex. The neocortex accounts for 90% of the cortex and is involved in higher functions such as thought and language. It is divided into 6-7 layers, with two main cell types: pyramidal cells and nonpyramidal cells. The surface of the neocortex is divided into separate areas, each given a number by Brodmann (e.g. Brodmann’s area 17 is the primary visual cortex). The surface is folded to increase surface area, with grooves called sulci and ridges called gyri. The neocortex is responsible for higher cognitive functions and is essential for human consciousness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 112 - Which type of apraxia is indicated when a patient is unable to fold...

    Incorrect

    • Which type of apraxia is indicated when a patient is unable to fold a piece of paper with their non-dominant hand and place it on a table during a mini mental state examination?

      Your Answer:

      Correct Answer: Ideational

      Explanation:

      If a patient is unable to complete a task that requires a sequence of steps, they are exhibiting ideational apraxia. On the other hand, if they struggle to perform a task that they have previously learned, such as attempting to brush their teeth with a pencil, this is an example of ideomotor apraxia.

      Apraxia: Understanding the Inability to Carry Out Learned Voluntary Movements

      Apraxia is a neurological condition that affects a person’s ability to carry out learned voluntary movements. It is important to note that this condition assumes that everything works and the person is not paralyzed. There are different types of apraxia, each with its own set of symptoms and characteristics.

      Limb kinetic apraxia is a type of apraxia that affects a person’s ability to make fine of delicate movements. This can include tasks such as buttoning a shirt of tying shoelaces.

      Ideomotor apraxia, on the other hand, is an inability to carry out learned tasks when given the necessary objects. For example, a person with ideomotor apraxia may try to write with a hairbrush instead of using it to brush their hair.

      Constructional apraxia affects a person’s ability to copy a picture of combine parts of something to form a whole. This can include tasks such as building a puzzle of drawing a picture.

      Ideational apraxia is an inability to follow a sequence of actions in the correct order. For example, a person with ideational apraxia may struggle to take a match out of a box and strike it with their left hand.

      Finally, oculomotor apraxia affects a person’s ability to control eye movements. This can make it difficult for them to track moving objects of read smoothly.

      Overall, apraxia can have a significant impact on a person’s ability to carry out everyday tasks. However, with the right support and treatment, many people with apraxia are able to improve their abilities and maintain their independence.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 113 - Which statement about variant CJD is accurate? ...

    Incorrect

    • Which statement about variant CJD is accurate?

      Your Answer:

      Correct Answer: It is associated with the pulvinar sign on the MRI

      Explanation:

      Creutzfeldt-Jakob Disease: Differences between vCJD and CJD

      Creutzfeldt-Jakob Disease (CJD) is a prion disease that includes scrapie, BSE, and Kuru. However, there are important differences between sporadic (also known as classic) CJD and variant CJD. The table below summarizes these differences.

      vCJD:
      – Longer duration from onset of symptoms to death (a year of more)
      – Presents with psychiatric and behavioral symptoms before neurological symptoms
      – MRI shows pulvinar sign
      – EEG shows generalized slowing
      – Originates from infected meat products
      – Affects younger people (age 25-30)

      CJD:
      – Shorter duration from onset of symptoms to death (a few months)
      – Presents with neurological symptoms
      – MRI shows bilateral anterior basal ganglia high signal
      – EEG shows biphasic and triphasic waves 1-2 per second
      – Originates from genetic mutation (bad luck)
      – Affects older people (age 55-65)

      Overall, understanding the differences between vCJD and CJD is important for diagnosis and treatment.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 114 - A 65-year-old woman is experiencing memory difficulties and has been diagnosed with Alzheimer's...

    Incorrect

    • A 65-year-old woman is experiencing memory difficulties and has been diagnosed with Alzheimer's disease. Which anatomical structure is most likely to exhibit atrophy in this scenario?

      Your Answer:

      Correct Answer: Hippocampus

      Explanation:

      The frontal lobe is located at the front of the cerebrum and is responsible for managing executive functions and working memory. The hippocampus plays a role in spatial navigation and the consolidation of short term memory to long term memory, but is often the first region of the brain to suffer damage in Alzheimer’s disease. The corpus callosum is a bundle of nerve fibers that connects the left and right cerebral hemispheres, facilitating communication between them. The thalamus is a symmetrical midline structure that relays sensory and motor signals to the cerebral cortex, while also regulating consciousness, alertness, and sleep. Broca’s area, which is typically located in the inferior frontal gyrus, is a key region involved in language production.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 115 - What is the cell type that offers structural support in the central nervous...

    Incorrect

    • What is the cell type that offers structural support in the central nervous system?

      Your Answer:

      Correct Answer: Astrocyte

      Explanation:

      Glial Cells: The Support System of the Central Nervous System

      The central nervous system is composed of two basic cell types: neurons and glial cells. Glial cells, also known as support cells, play a crucial role in maintaining the health and function of neurons. There are several types of glial cells, including macroglia (astrocytes and oligodendrocytes), ependymal cells, and microglia.

      Astrocytes are the most abundant type of glial cell and have numerous functions, such as providing structural support, repairing nervous tissue, nourishing neurons, contributing to the blood-brain barrier, and regulating neurotransmission and blood flow. There are two main types of astrocytes: protoplasmic and fibrous.

      Oligodendrocytes are responsible for the formation of myelin sheaths, which insulate and protect axons, allowing for faster and more efficient transmission of nerve impulses.

      Ependymal cells line the ventricular system and are involved in the circulation of cerebrospinal fluid (CSF) and fluid homeostasis in the brain. Specialized ependymal cells called choroid plexus cells produce CSF.

      Microglia are the immune cells of the CNS and play a crucial role in protecting the brain from infection and injury. They also contribute to the maintenance of neuronal health and function.

      In summary, glial cells are essential for the proper functioning of the central nervous system. They provide structural support, nourishment, insulation, and immune defense to neurons, ensuring the health and well-being of the brain and spinal cord.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 116 - What neuroimaging result is the strongest indicator of new variant CJD? ...

    Incorrect

    • What neuroimaging result is the strongest indicator of new variant CJD?

      Your Answer:

      Correct Answer: Increased signal in the pulvinar nucleus of thalamus bilaterally

      Explanation:

      Creutzfeldt-Jakob Disease: Differences between vCJD and CJD

      Creutzfeldt-Jakob Disease (CJD) is a prion disease that includes scrapie, BSE, and Kuru. However, there are important differences between sporadic (also known as classic) CJD and variant CJD. The table below summarizes these differences.

      vCJD:
      – Longer duration from onset of symptoms to death (a year of more)
      – Presents with psychiatric and behavioral symptoms before neurological symptoms
      – MRI shows pulvinar sign
      – EEG shows generalized slowing
      – Originates from infected meat products
      – Affects younger people (age 25-30)

      CJD:
      – Shorter duration from onset of symptoms to death (a few months)
      – Presents with neurological symptoms
      – MRI shows bilateral anterior basal ganglia high signal
      – EEG shows biphasic and triphasic waves 1-2 per second
      – Originates from genetic mutation (bad luck)
      – Affects older people (age 55-65)

      Overall, understanding the differences between vCJD and CJD is important for diagnosis and treatment.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 117 - What is the structure that separates the frontal and parietal lobes above from...

    Incorrect

    • What is the structure that separates the frontal and parietal lobes above from the temporal lobe below?

      Your Answer:

      Correct Answer: The Sylvian fissure

      Explanation:

      Gross Anatomy

      The brain is divided into different lobes and regions by the many fissures of grooves on its surface. It is important to be aware of some anatomical landmarks such as the medial longitudinal fissure, which separates the brain into the right and left hemispheres. Another important landmark is the lateral sulcus of the Sylvian fissure, which divides the frontal and parietal lobes above from the temporal lobe below. Additionally, the central sulcus of the fissure of Rolando separates the frontal from the parietal lobe. Understanding these anatomical landmarks is crucial in identifying and locating different areas of the brain.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 118 - What indicators would suggest the existence of a lower motor neuron lesion rather...

    Incorrect

    • What indicators would suggest the existence of a lower motor neuron lesion rather than an upper motor neuron lesion?

      Your Answer:

      Correct Answer: Fasciculations

      Explanation:

      Motor Neuron Lesions

      Signs of an upper motor neuron lesion include weakness, increased reflexes, increased tone (spasticity), mild atrophy, an upgoing plantar response (Babinski reflex), and clonus. On the other hand, signs of a lower motor neuron lesion include atrophy, weakness, fasciculations, decreased reflexes, and decreased tone. It is important to differentiate between the two types of lesions as they have different underlying causes and require different treatment approaches. A thorough neurological examination can help identify the location and extent of the lesion, which can guide further diagnostic testing and management.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 119 - Which of the following is not a component of the syndrome of frontotemporal...

    Incorrect

    • Which of the following is not a component of the syndrome of frontotemporal lobe degeneration (FTLD)?

      Your Answer:

      Correct Answer: Posterior cortical atrophy

      Explanation:

      Frontotemporal lobe degeneration (FTLD) encompasses various syndromes, such as Pick’s disease, primary progressive aphasia (which impacts speech), semantic dementia (affecting conceptual knowledge), and corticobasal degeneration (characterized by asymmetrical akinetic-rigid syndrome and apraxia). It is important to note that posterior cortical atrophy, which involves tissue loss in the posterior regions and affects higher visual processing, is not considered a part of the FTLD syndrome.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 120 - What is the extracellular ion that contributes to the resting membrane potential of...

    Incorrect

    • What is the extracellular ion that contributes to the resting membrane potential of a neuron due to its high concentration?

      Your Answer:

      Correct Answer: Na

      Explanation:

      Understanding Action Potentials in Neurons and Muscle Cells

      The membrane potential is a crucial aspect of cell physiology, and it exists across the plasma membrane of most cells. However, in neurons and muscle cells, this membrane potential can change over time. When a cell is not stimulated, it is in a resting state, and the inside of the cell is negatively charged compared to the outside. This resting membrane potential is typically around -70mV, and it is maintained by the Na/K pump, which maintains a high concentration of Na outside and K inside the cell.

      To trigger an action potential, the membrane potential must be raised to around -55mV. This can occur when a neurotransmitter binds to the postsynaptic neuron and opens some ion channels. Once the membrane potential reaches -55mV, a cascade of events is initiated, leading to the opening of a large number of Na channels and causing the cell to depolarize. As the membrane potential reaches around +40 mV, the Na channels close, and the K gates open, allowing K to flood out of the cell and causing the membrane potential to fall back down. This process is irreversible and is critical for the transmission of signals in neurons and the contraction of muscle cells.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 121 - A 42 year old, overweight woman presents with recurring episodes of one-sided vision...

    Incorrect

    • A 42 year old, overweight woman presents with recurring episodes of one-sided vision loss accompanied by pain over the last 24 months. She is curious if her use of fluoxetine, which you prescribed for her depression, could be a contributing factor. What is your primary suspicion regarding her symptoms?

      Your Answer:

      Correct Answer: Multiple sclerosis

      Explanation:

      The symptoms experienced by the woman are most indicative of optic neuritis, which is characterized by inflammation of the optic nerve where it connects to the eye. This typically results in temporary loss of vision in one eye, accompanied by pain during eye movement. Optic neuritis is commonly associated with multiple sclerosis. It is unlikely that the woman is experiencing an arterial occlusion, as this would cause permanent and painless vision loss. A pituitary adenoma would affect both eyes and result in permanent vision loss. The possibility of a somatoform disorder is unlikely, as the women’s symptoms align with a recognized medical diagnosis. Endophthalmitis is a serious condition that can cause permanent vision loss and requires immediate medical attention.

      Multiple Sclerosis: An Overview

      Multiple sclerosis is a neurological disorder that is classified into three categories: primary progressive, relapsing-remitting, and secondary progressive. Primary progressive multiple sclerosis affects 5-10% of patients and is characterized by a steady progression with no remissions. Relapsing-remitting multiple sclerosis affects 20-30% of patients and presents with a relapsing-remitting course but does not lead to serious disability. Secondary progressive multiple sclerosis affects 60% of patients and initially presents with a relapsing-remitting course but is then followed by a phase of progressive deterioration.

      The disorder typically begins between the ages of 20 and 40 and is characterized by multiple demyelinating lesions that have a preference for the optic nerves, cerebellum, brainstem, and spinal cord. Patients with multiple sclerosis present with a variety of neurological signs that reflect the presence and distribution of plaques. Ocular features of multiple sclerosis include optic neuritis, internuclear ophthalmoplegia, and ocular motor cranial neuropathy.

      Multiple sclerosis is more common in women than in men and is seen with increasing frequency as the distance from the equator increases. It is believed to be caused by a combination of genetic and environmental factors, with monozygotic concordance at 25%. Overall, multiple sclerosis is a predominantly white matter disease that can have a significant impact on a patient’s quality of life.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 122 - A child is referred to a neurologist. On entering the neurologist's room, the...

    Incorrect

    • A child is referred to a neurologist. On entering the neurologist's room, the child is observed to have a broad-based gait. When introduced, the child's speech is noted to be abnormal. When the child attempts to shake the doctor's hand, a tremor is observed. Which area of the brain is likely to be dysfunctional?

      Your Answer:

      Correct Answer: Cerebellum

      Explanation:

      Cerebellar Dysfunction: Symptoms and Signs

      Cerebellar dysfunction is a condition that affects the cerebellum, a part of the brain responsible for coordinating movement and balance. The symptoms and signs of cerebellar dysfunction include ataxia, intention tremor, nystagmus, broad-based gait, slurred speech, dysdiadochokinesis, and dysmetria (lack of finger-nose coordination).

      Ataxia refers to the lack of coordination of voluntary movements, resulting in unsteady gait, difficulty with balance, and clumsiness. Intention tremor is a type of tremor that occurs during voluntary movements, such as reaching for an object. Nystagmus is an involuntary movement of the eyes, characterized by rapid, jerky movements.

      Broad-based gait refers to a wide stance while walking, which is often seen in individuals with cerebellar dysfunction. Slurred speech, also known as dysarthria, is a common symptom of cerebellar dysfunction, which affects the ability to articulate words clearly. Dysdiadochokinesis is the inability to perform rapid alternating movements, such as tapping the fingers on the palm of the hand.

      Dysmetria refers to the inability to accurately judge the distance and direction of movements, resulting in errors in reaching for objects of touching the nose with the finger. These symptoms and signs of cerebellar dysfunction can be caused by a variety of conditions, including stroke, multiple sclerosis, and alcoholism. Treatment depends on the underlying cause and may include medications, physical therapy, and surgery.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 123 - The primary role of the suprachiasmatic nuclei is to regulate control over which...

    Incorrect

    • The primary role of the suprachiasmatic nuclei is to regulate control over which of the following?

      Your Answer:

      Correct Answer: Circadian rhythms

      Explanation:

      Functions of the Hypothalamus

      The hypothalamus is a vital part of the brain that plays a crucial role in regulating various bodily functions. It receives and integrates sensory information about the internal environment and directs actions to control internal homeostasis. The hypothalamus contains several nuclei and fiber tracts, each with specific functions.

      The suprachiasmatic nucleus (SCN) is responsible for regulating circadian rhythms. Neurons in the SCN have an intrinsic rhythm of discharge activity and receive input from the retina. The SCN is considered the body’s master clock, but it has multiple connections with other hypothalamic nuclei.

      Body temperature control is mainly under the control of the preoptic, anterior, and posterior nuclei, which have temperature-sensitive neurons. As the temperature goes above 37ºC, warm-sensitive neurons are activated, triggering parasympathetic activity to promote heat loss. As the temperature goes below 37ºC, cold-sensitive neurons are activated, triggering sympathetic activity to promote conservation of heat.

      The hypothalamus also plays a role in regulating prolactin secretion. Dopamine is tonically secreted by dopaminergic neurons that project from the arcuate nucleus of the hypothalamus into the anterior pituitary gland via the tuberoinfundibular pathway. The dopamine that is released acts on lactotrophic cells through D2-receptors, inhibiting prolactin synthesis. In the absence of pregnancy of lactation, prolactin is constitutively inhibited by dopamine. Dopamine antagonists result in hyperprolactinemia, while dopamine agonists inhibit prolactin secretion.

      In summary, the hypothalamus is a complex structure that regulates various bodily functions, including circadian rhythms, body temperature, and prolactin secretion. Dysfunction of the hypothalamus can lead to various disorders, such as sleep-rhythm disorder, diabetes insipidus, hyperprolactinemia, and obesity.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 124 - A 45-year-old man experiences a stroke caused by a ruptured berry aneurysm in...

    Incorrect

    • A 45-year-old man experiences a stroke caused by a ruptured berry aneurysm in the middle cerebral artery.
      What tests would you anticipate to show abnormalities?

      Your Answer:

      Correct Answer: Luria's motor test

      Explanation:

      Damage to the frontal lobe can impact sequencing abilities, as evidenced by Luria’s motor test which involves performing a sequence of fist-edge-palm movements. Additionally, the anterior cerebral artery is responsible for supplying blood to the frontal lobes.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 125 - What is a true statement about multisystem atrophy? ...

    Incorrect

    • What is a true statement about multisystem atrophy?

      Your Answer:

      Correct Answer: Associated Parkinson's symptoms respond poorly to levodopa

      Explanation:

      Parkinson plus syndromes, including multisystem atrophy, exhibit a limited efficacy towards Parkinson’s treatment, such as levodopa.

      Multisystem Atrophy: A Parkinson Plus Syndrome

      Multisystem atrophy is a type of Parkinson plus syndrome that is characterized by three main features: Parkinsonism, autonomic failure, and cerebellar ataxia. It can present in three different ways, including Shy-Drager Syndrome, Striatonigral degeneration, and Olivopontocerebellar atrophy, each with varying degrees of the three main features.

      Macroscopic features of multisystem atrophy include pallor of the substantia nigra, greenish discoloration and atrophy of the putamen, and cerebellar atrophy. Microscopic features include the presence of Papp-Lantos bodies, which are alpha-synuclein inclusions found in oligodendrocytes in the substantia nigra, cerebellum, and basal ganglia.

      Overall, multisystem atrophy is a complex and debilitating condition that affects multiple systems in the body, leading to a range of symptoms and challenges for patients and their caregivers.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 126 - You are asked to review a child on the ward who the staff...

    Incorrect

    • You are asked to review a child on the ward who the staff noted had a sudden and brief (one minute) episode whereby they went into what they described as a trance-like state. During this time the child was unresponsive and was seen to be picking aimlessly at their clothes. Following this episode the child did not recall being unresponsive but did report that before this happened they felt a strange sense of unfamiliarity. Which of the following epilepsy types would you most suspect?:

      Your Answer:

      Correct Answer: Complex partial seizure

      Explanation:

      The indication of a complex partial seizure is strongly implied by the absence of knowledge regarding aura.

      Epilepsy and Aura

      An aura is a subjective sensation that is a type of simple partial seizure. It typically lasts only a few seconds and can help identify the site of cortical onset. There are eight recognized types of auras, including somatosensory, visual, auditory, gustatory, olfactory, autonomic, abdominal, and psychic.

      In about 80% of cases, auras precede temporal lobe seizures. The most common auras in these seizures are abdominal and psychic, which can cause a rising epigastric sensation of feelings of fear, déjà vu, of jamais vu. Parietal lobe seizures may begin with a contralateral sensation, usually of the positive type, such as an electrical sensation of tingling. Occipital lobe seizures may begin with contralateral visual changes, such as colored lines, spots, of shapes, of even a loss of vision. Temporal-parietal-occipital seizures may produce more formed auras.

      Complex partial seizures are defined by impairment of consciousness, which means decreased responsiveness and awareness of oneself and surroundings. During a complex partial seizure, a patient is unresponsive and does not remember events that occurred.

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      • Neurosciences
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  • Question 127 - Which condition is most likely to exhibit a hyperkinetic gait? ...

    Incorrect

    • Which condition is most likely to exhibit a hyperkinetic gait?

      Your Answer:

      Correct Answer: Sydenham chorea

      Explanation:

      Gait disorders can be caused by a variety of conditions, including neurological, muscular, and structural abnormalities. One common gait disorder is hemiplegic gait, which is characterized by unilateral weakness on the affected side, with the arm flexed, adducted, and internally rotated, and the leg on the same side in extension with plantar flexion of the foot and toes. When walking, the patient may hold their arm to one side and drag their affected leg in a semicircle (circumduction) due to weakness of leg flexors and extended foot. Hemiplegic gait is often seen in patients who have suffered a stroke.

      Other gait disorders include ataxic gait, spastic gait, and steppage gait, each with their own unique characteristics and associated conditions. Accurate diagnosis and treatment of gait disorders is important for improving mobility and quality of life for affected individuals.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 128 - Which of the following is enlarged in individuals with schizophrenia? ...

    Incorrect

    • Which of the following is enlarged in individuals with schizophrenia?

      Your Answer:

      Correct Answer: The ventricles

      Explanation:

      Ventricular enlargement is a common finding in individuals with schizophrenia.

      Schizophrenia is a pathology that is characterized by a number of structural and functional brain alterations. Structural alterations include enlargement of the ventricles, reductions in total brain and gray matter volume, and regional reductions in the amygdala, parahippocampal gyrus, and temporal lobes. Antipsychotic treatment may be associated with gray matter loss over time, and even drug-naïve patients show volume reductions. Cerebral asymmetry is also reduced in affected individuals and healthy relatives. Functional alterations include diminished activation of frontal regions during cognitive tasks and increased activation of temporal regions during hallucinations. These findings suggest that schizophrenia is associated with both macroscopic and functional changes in the brain.

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      • Neurosciences
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  • Question 129 - What type of apraxia is demonstrated by the difficulty in reproducing intersecting pentagons...

    Incorrect

    • What type of apraxia is demonstrated by the difficulty in reproducing intersecting pentagons on the MMSE?

      Your Answer:

      Correct Answer: Constructional

      Explanation:

      Apraxia: Understanding the Inability to Carry Out Learned Voluntary Movements

      Apraxia is a neurological condition that affects a person’s ability to carry out learned voluntary movements. It is important to note that this condition assumes that everything works and the person is not paralyzed. There are different types of apraxia, each with its own set of symptoms and characteristics.

      Limb kinetic apraxia is a type of apraxia that affects a person’s ability to make fine of delicate movements. This can include tasks such as buttoning a shirt of tying shoelaces.

      Ideomotor apraxia, on the other hand, is an inability to carry out learned tasks when given the necessary objects. For example, a person with ideomotor apraxia may try to write with a hairbrush instead of using it to brush their hair.

      Constructional apraxia affects a person’s ability to copy a picture of combine parts of something to form a whole. This can include tasks such as building a puzzle of drawing a picture.

      Ideational apraxia is an inability to follow a sequence of actions in the correct order. For example, a person with ideational apraxia may struggle to take a match out of a box and strike it with their left hand.

      Finally, oculomotor apraxia affects a person’s ability to control eye movements. This can make it difficult for them to track moving objects of read smoothly.

      Overall, apraxia can have a significant impact on a person’s ability to carry out everyday tasks. However, with the right support and treatment, many people with apraxia are able to improve their abilities and maintain their independence.

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      • Neurosciences
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  • Question 130 - From which amino acid is noradrenaline (norepinephrine) derived? ...

    Incorrect

    • From which amino acid is noradrenaline (norepinephrine) derived?

      Your Answer:

      Correct Answer: Tyrosine

      Explanation:

      Catecholamines are a group of chemical compounds that have a distinct structure consisting of a benzene ring with two hydroxyl groups, an intermediate ethyl chain, and a terminal amine group. These compounds play an important role in the body and are involved in various physiological processes. The three main catecholamines found in the body are dopamine, adrenaline, and noradrenaline. All of these compounds are derived from the amino acid tyrosine. Overall, catecholamines are essential for maintaining proper bodily functions and are involved in a wide range of physiological processes.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 131 - What is the term used to describe the condition where a person cannot...

    Incorrect

    • What is the term used to describe the condition where a person cannot identify faces?

      Your Answer:

      Correct Answer: Prosopagnosia

      Explanation:

      Agnosia is a condition where a person loses the ability to recognize objects, persons, sounds, shapes, of smells, despite having no significant memory loss of defective senses. There are different types of agnosia, such as prosopagnosia (inability to recognize familiar faces), anosognosia (inability to recognize one’s own condition/illness), autotopagnosia (inability to orient parts of the body), phonagnosia (inability to recognize familiar voices), simultanagnosia (inability to appreciate two objects in the visual field at the same time), and astereoagnosia (inability to recognize objects by touch).

    • This question is part of the following fields:

      • Neurosciences
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  • Question 132 - In what type of epilepsy is it most common to experience an aura?...

    Incorrect

    • In what type of epilepsy is it most common to experience an aura?

      Your Answer:

      Correct Answer: Temporal lobe

      Explanation:

      This question is presented in two variations on the exam, with one implying that auras are primarily linked to temporal lobe epilepsy and the other to complex partial seizures. In reality, partial seizures are most commonly associated with auras compared to other types of seizures. While partial seizures can originate in any lobe of the brain, those that arise in the temporal lobe are most likely to produce an aura. Therefore, both versions of the question are accurate.

      Epilepsy and Aura

      An aura is a subjective sensation that is a type of simple partial seizure. It typically lasts only a few seconds and can help identify the site of cortical onset. There are eight recognized types of auras, including somatosensory, visual, auditory, gustatory, olfactory, autonomic, abdominal, and psychic.

      In about 80% of cases, auras precede temporal lobe seizures. The most common auras in these seizures are abdominal and psychic, which can cause a rising epigastric sensation of feelings of fear, déjà vu, of jamais vu. Parietal lobe seizures may begin with a contralateral sensation, usually of the positive type, such as an electrical sensation of tingling. Occipital lobe seizures may begin with contralateral visual changes, such as colored lines, spots, of shapes, of even a loss of vision. Temporal-parietal-occipital seizures may produce more formed auras.

      Complex partial seizures are defined by impairment of consciousness, which means decreased responsiveness and awareness of oneself and surroundings. During a complex partial seizure, a patient is unresponsive and does not remember events that occurred.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 133 - Which sensory component is correctly matched with its corresponding cranial nerve reflex? ...

    Incorrect

    • Which sensory component is correctly matched with its corresponding cranial nerve reflex?

      Your Answer:

      Correct Answer: Gag reflex - IX cranial nerve

      Explanation:

      The question specifically requests the sensory aspect.

      Cranial Nerve Reflexes

      When it comes to questions on cranial nerve reflexes, it is important to match the reflex to the nerves involved. Here are some examples:

      – Pupillary light reflex: involves the optic nerve (sensory) and oculomotor nerve (motor).
      – Accommodation reflex: involves the optic nerve (sensory) and oculomotor nerve (motor).
      – Jaw jerk: involves the trigeminal nerve (sensory and motor).
      – Corneal reflex: involves the trigeminal nerve (sensory) and facial nerve (motor).
      – Vestibulo-ocular reflex: involves the vestibulocochlear nerve (sensory) and oculomotor, trochlear, and abducent nerves (motor).

      Another example of a cranial nerve reflex is the gag reflex, which involves the glossopharyngeal nerve (sensory) and the vagus nerve (motor). This reflex is important for protecting the airway from foreign objects of substances that may trigger a gag reflex. It is also used as a diagnostic tool to assess the function of these nerves.

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      • Neurosciences
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  • Question 134 - What condition is identified by the existence of Pick bodies? ...

    Incorrect

    • What condition is identified by the existence of Pick bodies?

      Your Answer:

      Correct Answer: Frontotemporal dementia

      Explanation:

      Frontotemporal Lobar Degeneration (FTLD) is a pathological term that refers to a group of neurodegenerative disorders that affect the frontal and temporal lobes of the brain. FTLD is classified into several subtypes based on the main protein component of neuronal and glial abnormal inclusions and their distribution. The three main proteins associated with FTLD are Tau, TDP-43, and FUS. Each FTD clinical phenotype has been associated with different proportions of these proteins. Macroscopic changes in FTLD include atrophy of the frontal and temporal lobes, with focal gyral atrophy that resembles knives. Microscopic changes in FTLD-Tau include neuronal and glial tau aggregation, with further sub-classification based on the existence of different isoforms of tau protein. FTLD-TDP is characterized by cytoplasmic inclusions of TDP-43 in neurons, while FTLD-FUS is characterized by cytoplasmic inclusions of FUS.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 135 - What is the most likely diagnosis when an MRI shows high signal in...

    Incorrect

    • What is the most likely diagnosis when an MRI shows high signal in the medial aspects of both thalami that is bilateral and symmetrical?

      Your Answer:

      Correct Answer: Variant CJD

      Explanation:

      The pulvinar sign seen on radiological imaging can indicate several possible conditions, including Alper’s Syndrome, cat-scratch disease, and post-infectious encephalitis. It may also be present in cases of M/V2 subtype of sporadic CJD, thalamic infarctions, and top-of-the-basilar ischemia. However, when considering vCJD, the pulvinar sign should be evaluated in the appropriate clinical context.

      Creutzfeldt-Jakob Disease: Differences between vCJD and CJD

      Creutzfeldt-Jakob Disease (CJD) is a prion disease that includes scrapie, BSE, and Kuru. However, there are important differences between sporadic (also known as classic) CJD and variant CJD. The table below summarizes these differences.

      vCJD:
      – Longer duration from onset of symptoms to death (a year of more)
      – Presents with psychiatric and behavioral symptoms before neurological symptoms
      – MRI shows pulvinar sign
      – EEG shows generalized slowing
      – Originates from infected meat products
      – Affects younger people (age 25-30)

      CJD:
      – Shorter duration from onset of symptoms to death (a few months)
      – Presents with neurological symptoms
      – MRI shows bilateral anterior basal ganglia high signal
      – EEG shows biphasic and triphasic waves 1-2 per second
      – Originates from genetic mutation (bad luck)
      – Affects older people (age 55-65)

      Overall, understanding the differences between vCJD and CJD is important for diagnosis and treatment.

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      • Neurosciences
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  • Question 136 - Are athetoid movements commonly associated with basal ganglia dysfunction rather than cerebellar dysfunction?...

    Incorrect

    • Are athetoid movements commonly associated with basal ganglia dysfunction rather than cerebellar dysfunction?

      Your Answer:

      Correct Answer: Athetoid movements

      Explanation:

      Abnormal movements known as athetoid movements are commonly associated with issues in the basal ganglia.

      Cerebellar Dysfunction: Symptoms and Signs

      Cerebellar dysfunction is a condition that affects the cerebellum, a part of the brain responsible for coordinating movement and balance. The symptoms and signs of cerebellar dysfunction include ataxia, intention tremor, nystagmus, broad-based gait, slurred speech, dysdiadochokinesis, and dysmetria (lack of finger-nose coordination).

      Ataxia refers to the lack of coordination of voluntary movements, resulting in unsteady gait, difficulty with balance, and clumsiness. Intention tremor is a type of tremor that occurs during voluntary movements, such as reaching for an object. Nystagmus is an involuntary movement of the eyes, characterized by rapid, jerky movements.

      Broad-based gait refers to a wide stance while walking, which is often seen in individuals with cerebellar dysfunction. Slurred speech, also known as dysarthria, is a common symptom of cerebellar dysfunction, which affects the ability to articulate words clearly. Dysdiadochokinesis is the inability to perform rapid alternating movements, such as tapping the fingers on the palm of the hand.

      Dysmetria refers to the inability to accurately judge the distance and direction of movements, resulting in errors in reaching for objects of touching the nose with the finger. These symptoms and signs of cerebellar dysfunction can be caused by a variety of conditions, including stroke, multiple sclerosis, and alcoholism. Treatment depends on the underlying cause and may include medications, physical therapy, and surgery.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 137 - What is divided by the Sylvian fissure? ...

    Incorrect

    • What is divided by the Sylvian fissure?

      Your Answer:

      Correct Answer: The frontal and parietal lobes from the temporal lobe

      Explanation:

      The temporal lobe is separated from the frontal and parietal lobes by the Sylvian fissure.

      The Cerebral Cortex and Neocortex

      The cerebral cortex is the outermost layer of the cerebral hemispheres and is composed of three parts: the archicortex, paleocortex, and neocortex. The neocortex accounts for 90% of the cortex and is involved in higher functions such as thought and language. It is divided into 6-7 layers, with two main cell types: pyramidal cells and nonpyramidal cells. The surface of the neocortex is divided into separate areas, each given a number by Brodmann (e.g. Brodmann’s area 17 is the primary visual cortex). The surface is folded to increase surface area, with grooves called sulci and ridges called gyri. The neocortex is responsible for higher cognitive functions and is essential for human consciousness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 138 - What is the term used to describe the small, horizontally arranged folds resembling...

    Incorrect

    • What is the term used to describe the small, horizontally arranged folds resembling pleats on the outer surface of the cerebellum?

      Your Answer:

      Correct Answer: Folia

      Explanation:

      Brain Anatomy

      The brain is a complex organ with various regions responsible for different functions. The major areas of the cerebrum (telencephalon) include the frontal lobe, parietal lobe, occipital lobe, temporal lobe, insula, corpus callosum, fornix, anterior commissure, and striatum. The cerebrum is responsible for complex learning, language acquisition, visual and auditory processing, memory, and emotion processing.

      The diencephalon includes the thalamus, hypothalamus and pituitary, pineal gland, and mammillary body. The thalamus is a major relay point and processing center for all sensory impulses (excluding olfaction). The hypothalamus and pituitary are involved in homeostasis and hormone release. The pineal gland secretes melatonin to regulate circadian rhythms. The mammillary body is a relay point involved in memory.

      The cerebellum is primarily concerned with movement and has two major hemispheres with an outer cortex made up of gray matter and an inner region of white matter. The cerebellum provides precise timing and appropriate patterns of skeletal muscle contraction for smooth, coordinated movements and agility needed for daily life.

      The brainstem includes the substantia nigra, which is involved in controlling and regulating activities of the motor and premotor cortical areas for smooth voluntary movements, eye movement, reward seeking, the pleasurable effects of substance misuse, and learning.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 139 - An elevation in Brain-derived neurotrophic factor levels in cortical regions compared to healthy...

    Incorrect

    • An elevation in Brain-derived neurotrophic factor levels in cortical regions compared to healthy individuals has been observed for which of the following disorders?

      Your Answer:

      Correct Answer: Schizophrenia

      Explanation:

      Neurotrophins: Crucial for Neuronal Growth and Development

      Neurotrophins are essential for the growth and development of neurons. However, disturbances in neurotrophic factors may contribute to some neurodevelopmental aspects of schizophrenia and major depression.

      Studies have shown that patients with schizophrenia have increased concentrations of Brain-derived neurotrophic factor (BDNF) in cortical areas, but decreased levels in the hippocampus compared to controls. Additionally, patients with schizophrenia have lower concentrations of neurotrophin-3 in frontal and parietal areas than controls.

      These findings suggest that neurotrophins play a critical role in the pathophysiology of schizophrenia and major depression. Further research is needed to fully understand the mechanisms underlying these disturbances in neurotrophic factors.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 140 - What is a correct statement about the blood brain barrier? ...

    Incorrect

    • What is a correct statement about the blood brain barrier?

      Your Answer:

      Correct Answer: It is fenestrated at the posterior pituitary gland

      Explanation:

      Understanding the Blood Brain Barrier

      The blood brain barrier (BBB) is a crucial component of the brain’s defense system against harmful chemicals and ion imbalances. It is a semi-permeable membrane formed by tight junctions of endothelial cells in the brain’s capillaries, which separates the blood from the cerebrospinal fluid. However, certain areas of the BBB, known as circumventricular organs, are fenestrated to allow neurosecretory products to enter the blood.

      When it comes to MRCPsych questions, the focus is on the following aspects of the BBB: the tight junctions between endothelial cells, the ease with which lipid-soluble molecules pass through compared to water-soluble ones, the difficulty large and highly charged molecules face in passing through, the increased permeability of the BBB during inflammation, and the theoretical ability of nasally administered drugs to bypass the BBB.

      It is important to remember the specific circumventricular organs where the BBB is fenestrated, including the posterior pituitary and the area postrema. Understanding the BBB’s function and characteristics is essential for medical professionals to diagnose and treat neurological disorders effectively.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 141 - Which area is believed to have the primary role in psychosis due to...

    Incorrect

    • Which area is believed to have the primary role in psychosis due to an overabundance of dopaminergic activity?

      Your Answer:

      Correct Answer: Striatum

      Explanation:

      The Dopamine Hypothesis is a theory that suggests that dopamine and dopaminergic mechanisms are central to schizophrenia. This hypothesis was developed based on observations that antipsychotic drugs provide at least some degree of D2-type dopamine receptor blockade and that it is possible to induce a psychotic episode in healthy subjects with pharmacological dopamine agonists. The hypothesis was further strengthened by the finding that antipsychotic drugs’ clinical effectiveness was directly related to their affinity for dopamine receptors. Initially, the belief was that the problem related to an excess of dopamine in the brain. However, later studies showed that the relationship between hypofrontality and low cerebrospinal fluid (CSF) dopamine metabolite levels indicates low frontal dopamine levels. Thus, there was a move from a one-sided dopamine hypothesis explaining all facets of schizophrenia to a regionally specific prefrontal hypodopaminergia and a subcortical hyperdopaminergia. In summary, psychosis appears to result from excessive dopamine activity in the striatum, while the negative symptoms seen in schizophrenia appear to result from too little dopamine activity in the frontal lobe. Antipsychotic medications appear to help by countering the effects of increased dopamine by blocking postsynaptic D2 receptors in the striatum.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 142 - What evidence indicates a diagnosis of dementia pugilistica? ...

    Incorrect

    • What evidence indicates a diagnosis of dementia pugilistica?

      Your Answer:

      Correct Answer: A history of recurrent head injury

      Explanation:

      Dementia Pugilistica: A Neurodegenerative Condition Resulting from Neurotrauma

      Dementia pugilistica, also known as chronic traumatic encephalopathy (CTE), is a neurodegenerative condition that results from neurotrauma. It is commonly seen in boxers and NFL players, but can also occur in anyone with neurotrauma. The condition is characterized by symptoms such as gait ataxia, slurred speech, impaired hearing, tremors, disequilibrium, neurobehavioral disturbances, and progressive cognitive decline.

      Most cases of dementia pugilistica present with early onset cognitive deficits, and behavioral signs exhibited by patients include aggression, suspiciousness, paranoia, childishness, hypersexuality, depression, and restlessness. The progression of the condition leads to more prominent behavioral symptoms such as difficulty with impulse control, irritability, inappropriateness, and explosive outbursts of aggression.

      Neuropathological abnormalities have been identified in CTE, with the most unique feature being the abnormal accumulation of tau in neurons and glia in an irregular, focal, perivascular distribution and at the depths of cortical sulci. Abnormalities of the septum pellucidum, such as cavum and fenestration, are also a common feature.

      While the condition has become increasingly rare due to the progressive improvement in sports safety, it is important to recognize the potential long-term consequences of repeated head injuries and take steps to prevent them.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 143 - What is the most probable outcome of a blockage in the anterior cerebral...

    Incorrect

    • What is the most probable outcome of a blockage in the anterior cerebral artery?

      Your Answer:

      Correct Answer: Motor aphasia

      Explanation:

      The frontal part of the brain responsible for motor function is supplied by the anterior cerebral artery.

      Aphasia is a language impairment that affects the production of comprehension of speech, as well as the ability to read of write. The areas involved in language are situated around the Sylvian fissure, referred to as the ‘perisylvian language area’. For repetition, the primary auditory cortex, Wernicke, Broca via the Arcuate fasciculus (AF), Broca recodes into articulatory plan, primary motor cortex, and pyramidal system to cranial nerves are involved. For oral reading, the visual cortex to Wernicke and the same processes as for repetition follows. For writing, Wernicke via AF to premotor cortex for arm and hand, movement planned, sent to motor cortex. The classification of aphasia is complex and imprecise, with the Boston Group classification and Luria’s aphasia interpretation being the most influential. The important subtypes of aphasia include global aphasia, Broca’s aphasia, Wernicke’s aphasia, conduction aphasia, anomic aphasia, transcortical motor aphasia, and transcortical sensory aphasia. Additional syndromes include alexia without agraphia, alexia with agraphia, and pure word deafness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 144 - Which of these is not a typical symptom of epilepsy in the temporal...

    Incorrect

    • Which of these is not a typical symptom of epilepsy in the temporal lobe?

      Your Answer:

      Correct Answer: Visual aura

      Explanation:

      – Visual aura is not expected in temporal lobe epilepsy
      – Visual aura may occur in occipital seizures
      – Temporal lobe epilepsy is characterized by automatisms, altered consciousness, déjà vu, complex partial seizures, and olfactory hallucinations
      – Occipital epilepsy can cause visual phenomena and headaches
      – Occipital epilepsy should be differentiated from migraine

    • This question is part of the following fields:

      • Neurosciences
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  • Question 145 - Which statement about the anatomy of the basal ganglia is accurate? ...

    Incorrect

    • Which statement about the anatomy of the basal ganglia is accurate?

      Your Answer:

      Correct Answer: The subthalamic nucleus is part of the basal ganglia

      Explanation:

      The Basal Ganglia: Functions and Disorders

      The basal ganglia are a group of subcortical structures that play a crucial role in controlling movement and some cognitive processes. The components of the basal ganglia include the striatum (caudate, putamen, nucleus accumbens), subthalamic nucleus, globus pallidus, and substantia nigra (divided into pars compacta and pars reticulata). The putamen and globus pallidus are collectively referred to as the lenticular nucleus.

      The basal ganglia are connected in a complex loop, with the cortex projecting to the striatum, the striatum to the internal segment of the globus pallidus, the internal segment of the globus pallidus to the thalamus, and the thalamus back to the cortex. This loop is responsible for regulating movement and cognitive processes.

      However, problems with the basal ganglia can lead to several conditions. Huntington’s chorea is caused by degeneration of the caudate nucleus, while Wilson’s disease is characterized by copper deposition in the basal ganglia. Parkinson’s disease is associated with degeneration of the substantia nigra, and hemiballism results from damage to the subthalamic nucleus.

      In summary, the basal ganglia are a crucial part of the brain that regulate movement and some cognitive processes. Disorders of the basal ganglia can lead to significant neurological conditions that affect movement and other functions.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 146 - What is a true statement about cerebrovascular accidents? ...

    Incorrect

    • What is a true statement about cerebrovascular accidents?

      Your Answer:

      Correct Answer: Cerebral infarction commonly occurs during sleep

      Explanation:

      It is widely acknowledged that women who have pre-existing cardiovascular disease should avoid taking oral contraceptives due to the increased risk of stroke and DVTs.

      Cerebrovascular accidents (CVA), also known as strokes, are defined by the World Health Organization as a sudden onset of focal neurological symptoms lasting more than 24 hours and presumed to be of vascular origin. Strokes can be caused by either infarction of hemorrhage, with infarction being more common. Hemorrhagic strokes tend to be more severe. Intracranial hemorrhage can be primary, caused mainly by hypertension, of subarachnoid, caused by the rupture of an aneurysm of angioma. Primary intracranial hemorrhage is most common in individuals aged 60-80 and often occurs during exertion. Infarction can be caused by thrombosis of embolism, with thrombosis being more common. Atherosclerosis, often caused by hypertension, is the main cause of infarction. CT scanning is the preferred diagnostic tool during the first 48 hours after a stroke as it can distinguish between infarcts and hemorrhages. Recovery from embolism is generally quicker and more complete than from thrombosis due to the availability of collateral channels.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 147 - Which of the options below does not belong to the category of small...

    Incorrect

    • Which of the options below does not belong to the category of small molecule neurotransmitters?

      Your Answer:

      Correct Answer: Prolactin

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 148 - Which of the following symptoms is not associated with Gerstmann's syndrome? ...

    Incorrect

    • Which of the following symptoms is not associated with Gerstmann's syndrome?

      Your Answer:

      Correct Answer: Prosopagnosia

      Explanation:

      Gerstmann’s Syndrome: Symptoms and Brain Lesions

      Gerstmann’s syndrome is a condition that is characterized by several symptoms, including dyscalculia, dysgraphia, finger agnosia, and right-left disorientation. Patients with this syndrome have been found to have lesions in areas such as the left frontal posterior, left parietal, temporal, and occipital lobes. The left angular gyrus, which is located at the junction of the temporal, occipital, and parietal lobes, seems to be the main area of overlap. Although the function of the angular gyrus is not well understood, it is believed to be involved in various functions such as calculation, spatial reasoning, understanding of ordinal concepts, and comprehension of metaphors.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 149 - What is a component of the hypothalamus in terms of neuroanatomy? ...

    Incorrect

    • What is a component of the hypothalamus in terms of neuroanatomy?

      Your Answer:

      Correct Answer: Mammillary bodies

      Explanation:

      The striatum is composed of the caudate nucleus and putamen, which are part of the basal ganglia. The basal ganglia is the largest subcortical structure in the brain and consists of a group of grey matter nuclei located in the subcortical area. In contrast, the mammillary bodies are small round bodies that are part of the hypothalamus and play a crucial role in the Papez circuit as a component of the limbic system.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 150 - Which condition can be diagnosed based on an atypical tonsillar biopsy result? ...

    Incorrect

    • Which condition can be diagnosed based on an atypical tonsillar biopsy result?

      Your Answer:

      Correct Answer: Variant CJD

      Explanation:

      To confirm a diagnosis of variant CJD, a tonsillar biopsy is performed as it is the only form of CJD that impacts the lymph nodes.

      Creutzfeldt-Jakob Disease: Differences between vCJD and CJD

      Creutzfeldt-Jakob Disease (CJD) is a prion disease that includes scrapie, BSE, and Kuru. However, there are important differences between sporadic (also known as classic) CJD and variant CJD. The table below summarizes these differences.

      vCJD:
      – Longer duration from onset of symptoms to death (a year of more)
      – Presents with psychiatric and behavioral symptoms before neurological symptoms
      – MRI shows pulvinar sign
      – EEG shows generalized slowing
      – Originates from infected meat products
      – Affects younger people (age 25-30)

      CJD:
      – Shorter duration from onset of symptoms to death (a few months)
      – Presents with neurological symptoms
      – MRI shows bilateral anterior basal ganglia high signal
      – EEG shows biphasic and triphasic waves 1-2 per second
      – Originates from genetic mutation (bad luck)
      – Affects older people (age 55-65)

      Overall, understanding the differences between vCJD and CJD is important for diagnosis and treatment.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 151 - Which feature is not very useful in distinguishing between Parkinson's disease and progressive...

    Incorrect

    • Which feature is not very useful in distinguishing between Parkinson's disease and progressive supranuclear palsy?

      Your Answer:

      Correct Answer: Pallor of the substantia nigra

      Explanation:

      Both conditions exhibit pallor of the substantia nigra. However, in PSP, the locus coeruleus is typically unaffected, whereas in Parkinson’s disease, it shows pallor. Therefore, if there is pallor in this area, it would indicate Parkinson’s disease.

      Pathology of Progressive Supranuclear Palsy

      Progressive supranuclear palsy is a rare disorder that affects gait and balance, often accompanied by changes in mood, behavior, and dementia. The macroscopic changes observed in this condition include pallor of the substantia nigra (with sparing of the locus coeruleus), mild midbrain atrophy, atrophy of the superior cerebellar peduncles, and discolouration of the dentate nucleus. On a microscopic level, gliosis and the presence of neurofibrillary tangles and tau inclusions in both astrocytes and oligodendrocytes (coiled bodies) are observed, particularly in the substantia nigra, subthalamic nucleus, and globus pallidus.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 152 - Which brain system enables the integration of emotional sensory information between the cortex...

    Incorrect

    • Which brain system enables the integration of emotional sensory information between the cortex and hypothalamus?

      Your Answer:

      Correct Answer: Papez circuit

      Explanation:

      In 1937, James Papez proposed a neural circuit that explained how emotional experiences occur in the brain. According to Papez, sensory messages related to emotional stimuli are first received by the thalamus, which then directs them to both the cortex (stream of thinking) and hypothalamus (stream of feeling). The cingulate cortex integrates this information from the hypothalamus and sensory cortex, leading to emotional experiences. The output via the hippocampus and hypothalamus allows cortical control of emotional responses. This circuit has since been reconceptualized as the limbic system.

      The medial longitudinal fasciculus carries fibres from cranial nerves III, IV and IV. The nucleus accumbens plays a major role in the reward circuit, while the somatosensory cortex is involved in processing pain. The basal ganglia are involved in voluntary motor control.

      Overall, the Papez circuit theory provides a framework for understanding the functional neuroanatomy of emotion. It highlights the importance of the limbic system in emotional experiences and the role of various brain regions in processing different aspects of emotional stimuli.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 153 - From which substance is gamma-aminobutyric acid synthesized? ...

    Incorrect

    • From which substance is gamma-aminobutyric acid synthesized?

      Your Answer:

      Correct Answer: Glutamate

      Explanation:

      Glutamate is the precursor for the synthesis of GABA.

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 154 - If a man experiences a severe road traffic accident resulting in substantial damage...

    Incorrect

    • If a man experiences a severe road traffic accident resulting in substantial damage to his frontal lobe, what symptoms would you anticipate him to exhibit?

      Your Answer:

      Correct Answer: Contralateral hemiplegia

      Explanation:

      Cerebral Dysfunction: Lobe-Specific Features

      When the brain experiences dysfunction, it can manifest in various ways depending on the affected lobe. In the frontal lobe, dysfunction can lead to contralateral hemiplegia, impaired problem solving, disinhibition, lack of initiative, Broca’s aphasia, and agraphia (dominant). The temporal lobe dysfunction can result in Wernicke’s aphasia (dominant), homonymous upper quadrantanopia, and auditory agnosia (non-dominant). On the other hand, the non-dominant parietal lobe dysfunction can lead to anosognosia, dressing apraxia, spatial neglect, and constructional apraxia. Meanwhile, the dominant parietal lobe dysfunction can result in Gerstmann’s syndrome. Lastly, occipital lobe dysfunction can lead to visual agnosia, visual illusions, and contralateral homonymous hemianopia.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 155 - Which structure secretes adrenocorticotropic hormone in the HPA axis? ...

    Incorrect

    • Which structure secretes adrenocorticotropic hormone in the HPA axis?

      Your Answer:

      Correct Answer: Pituitary

      Explanation:

      The anterior lobe of the pituitary gland secretes adrenocorticotropic hormone.

      HPA Axis Dysfunction in Mood Disorders

      The HPA axis, which includes regulatory neural inputs and a feedback loop involving the hypothalamus, pituitary, and adrenal glands, plays a central role in the stress response. Excessive secretion of cortisol, a glucocorticoid hormone, can lead to disruptions in cellular functioning and widespread physiologic dysfunction. Dysregulation of the HPA axis is implicated in mood disorders such as depression and bipolar affective disorder.

      In depressed patients, cortisol levels often do not decrease as expected in response to the administration of dexamethasone, a synthetic corticosteroid. This abnormality in the dexamethasone suppression test is thought to be linked to genetic of acquired defects of glucocorticoid receptors. Tricyclic antidepressants have been shown to increase expression of glucocorticoid receptors, whereas this is not the case for SSRIs.

      Early adverse experiences can produce long standing changes in HPA axis regulation, indicating a possible neurobiological mechanism whereby childhood trauma could be translated into increased vulnerability to mood disorder. In major depression, there is hypersecretion of cortisol, corticotropin-releasing factor (CRF), and ACTH, and associated adrenocortical enlargement. HPA abnormalities have also been found in other psychiatric disorders including Alzheimer’s and PTSD.

      In bipolar disorder, dysregulation of ACTH and cortisol response after CRH stimulation have been reported. Abnormal DST results are found more often during depressive episodes in the course of bipolar disorder than in unipolar disorder. Reduced pituitary volume secondary to LHPA stimulation, resulting in pituitary hypoactivity, has been observed in bipolar patients.

      Overall, HPA axis dysfunction is implicated in mood disorders, and understanding the underlying mechanisms may lead to new opportunities for treatments.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 156 - Which process breaks down dopamine? ...

    Incorrect

    • Which process breaks down dopamine?

      Your Answer:

      Correct Answer: Monoamine oxidase

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 157 - A senior citizen is experiencing sedation during lurasidone dose titration. What is the...

    Incorrect

    • A senior citizen is experiencing sedation during lurasidone dose titration. What is the medication's minimum effective dose?

      Your Answer:

      Correct Answer: 37 mg

      Explanation:

      Lurasidone may cause akathisia and sedation as common side effects, which can vary based on the dosage. Its metabolic profile is neutral. However, doses lower than 37 mg are unlikely to produce desired results.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 158 - What is the most prevalent type of primary brain tumor found in adults?...

    Incorrect

    • What is the most prevalent type of primary brain tumor found in adults?

      Your Answer:

      Correct Answer: Glioblastoma multiforme

      Explanation:

      Cerebral Tumours

      The most common brain tumours in adults, listed in order of frequency, are metastatic tumours, glioblastoma multiforme, anaplastic astrocytoma, and meningioma. On the other hand, the most common brain tumours in children, listed in order of frequency, are astrocytoma, medulloblastoma, and ependymoma.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 159 - In addition to alcohol, what other substance is metabolized by aldehyde dehydrogenase? ...

    Incorrect

    • In addition to alcohol, what other substance is metabolized by aldehyde dehydrogenase?

      Your Answer:

      Correct Answer: Serotonin

      Explanation:

      Serotonin: Synthesis and Breakdown

      Serotonin, also known as 5-Hydroxytryptamine (5-HT), is synthesized in the central nervous system (CNS) in the raphe nuclei located in the brainstem, as well as in the gastrointestinal (GI) tract in enterochromaffin cells. The amino acid L-tryptophan, obtained from the diet, is used to synthesize serotonin. L-tryptophan can cross the blood-brain barrier, but serotonin cannot.

      The transformation of L-tryptophan into serotonin involves two steps. First, hydroxylation to 5-hydroxytryptophan is catalyzed by tryptophan hydroxylase. Second, decarboxylation of 5-hydroxytryptophan to serotonin (5-hydroxytryptamine) is catalyzed by L-aromatic amino acid decarboxylase.

      Serotonin is taken up from the synapse by a monoamine transporter (SERT). Substances that block this transporter include MDMA, amphetamine, cocaine, TCAs, and SSRIs. Serotonin is broken down by monoamine oxidase (MAO) and then by aldehyde dehydrogenase to 5-Hydroxyindoleacetic acid (5-HIAA).

    • This question is part of the following fields:

      • Neurosciences
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  • Question 160 - In a normal, healthy person during stage III sleep, what EEG patterns would...

    Incorrect

    • In a normal, healthy person during stage III sleep, what EEG patterns would be most expected to be observed?

      Your Answer:

      Correct Answer: Delta waves

      Explanation:

      Sleep Stages

      Sleep is divided into two distinct states called rapid eye movement (REM) and non-rapid eye movement (NREM). NREM is subdivided into four stages.

      Sleep stage
      Approx % of time spent in stage
      EEG findings
      Comment

      I
      5%
      Theta waves (4-7 Hz)
      The dozing off stage. Characterized by hypnic jerks: spontaneous myoclonic contractions associated with a sensation of twitching of falling.

      II
      45%
      Theta waves, K complexes and sleep spindles (short bursts of 12-14 Hz activity)
      Body enters a more subdued state including a drop in temperature, relaxed muscles, and slowed breathing and heart rate. At the same time, brain waves show a new pattern and eye movement stops.

      III
      15%
      Delta waves (0-4 Hz)
      Deepest stage of sleep (high waking threshold). The length of stage 3 decreases over the course of the night.

      IV
      15%
      Mixed, predominantly beta
      High dream activity.

      The percentage of REM sleep decreases with age.

      It takes the average person 15-20 minutes to fall asleep, this is called sleep latency (characterised by the onset of stage I sleep). Once asleep one descends through stages I-II and then III-IV (deep stages). After about 90 minutes of sleep one enters REM. The rest of the sleep comprises of cycles through the stages. As the sleep progresses the periods of REM become greater and the periods of NREM become less. During an average night’s sleep one spends 25% of the sleep in REM and 75% in NREM.

      REM sleep has certain characteristics that separate it from NREM

      Characteristics of REM sleep

      – Autonomic instability (variability in heart rate, respiratory rate, and BP)
      – Loss of muscle tone
      – Dreaming
      – Rapid eye movements
      – Penile erection

      Deafness:

      (No information provided on deafness in relation to sleep stages)

    • This question is part of the following fields:

      • Neurosciences
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  • Question 161 - Which receptor's agonist effect is most likely responsible for anorgasmia caused by SSRIs?...

    Incorrect

    • Which receptor's agonist effect is most likely responsible for anorgasmia caused by SSRIs?

      Your Answer:

      Correct Answer: 5HT2C

      Explanation:

      As an AI language model, I cannot provide a response without knowing the context of the rewrite you are referring to. Please provide more information of context so that I can assist you better.

      Serotonin (5-hydroxytryptamine, 5-HT) receptors are primarily G protein receptors, except for 5-HT3, which is a ligand-gated receptor. It is important to remember that 5-HT3 is most commonly associated with nausea. Additionally, 5-HT7 is linked to circadian rhythms. The stimulation of 5-HT2 receptors is believed to be responsible for the side effects of insomnia, agitation, and sexual dysfunction that are associated with the use of selective serotonin reuptake inhibitors (SSRIs).

    • This question is part of the following fields:

      • Neurosciences
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  • Question 162 - Which statement is false regarding microglia? ...

    Incorrect

    • Which statement is false regarding microglia?

      Your Answer:

      Correct Answer: They are neuronal cells

      Explanation:

      Microglia serve as the immune cells of the central nervous system and perform functions similar to macrophages. When a microglial cell engulfs infectious material, it is referred to as a Gitter cell.

      Glial Cells: The Support System of the Central Nervous System

      The central nervous system is composed of two basic cell types: neurons and glial cells. Glial cells, also known as support cells, play a crucial role in maintaining the health and function of neurons. There are several types of glial cells, including macroglia (astrocytes and oligodendrocytes), ependymal cells, and microglia.

      Astrocytes are the most abundant type of glial cell and have numerous functions, such as providing structural support, repairing nervous tissue, nourishing neurons, contributing to the blood-brain barrier, and regulating neurotransmission and blood flow. There are two main types of astrocytes: protoplasmic and fibrous.

      Oligodendrocytes are responsible for the formation of myelin sheaths, which insulate and protect axons, allowing for faster and more efficient transmission of nerve impulses.

      Ependymal cells line the ventricular system and are involved in the circulation of cerebrospinal fluid (CSF) and fluid homeostasis in the brain. Specialized ependymal cells called choroid plexus cells produce CSF.

      Microglia are the immune cells of the CNS and play a crucial role in protecting the brain from infection and injury. They also contribute to the maintenance of neuronal health and function.

      In summary, glial cells are essential for the proper functioning of the central nervous system. They provide structural support, nourishment, insulation, and immune defense to neurons, ensuring the health and well-being of the brain and spinal cord.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 163 - Which of the following conditions is not associated with a distinct EEG pattern?...

    Incorrect

    • Which of the following conditions is not associated with a distinct EEG pattern?

      Your Answer:

      Correct Answer: Variant CJD

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 164 - What is the most common subtype of Creutzfeldt-Jakob disease (CJD) that is responsible...

    Incorrect

    • What is the most common subtype of Creutzfeldt-Jakob disease (CJD) that is responsible for the majority of cases?

      Your Answer:

      Correct Answer: sCJDMM1 and sCJDMV1

      Explanation:

      CJD has several subtypes, including familial (fCJD), iatrogenic (iCJD), sporadic (sCJD), and new variant (vCJD). The most common subtype is sCJD, which makes up 85% of cases. sCJD can be further classified based on the MV polymorphisms at codon 129 of the PRNP gene, with sCJDMM1 and sCJDMV1 being the most prevalent subtypes. fCJD is the most common subtype after sCJD, while vCJD and iCJD are rare and caused by consuming contaminated food of tissue contamination from other humans, respectively.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 165 - What is a true statement about the neocortex? ...

    Incorrect

    • What is a true statement about the neocortex?

      Your Answer:

      Correct Answer: It contains both pyramidal and nonpyramidal cells

      Explanation:

      The Cerebral Cortex and Neocortex

      The cerebral cortex is the outermost layer of the cerebral hemispheres and is composed of three parts: the archicortex, paleocortex, and neocortex. The neocortex accounts for 90% of the cortex and is involved in higher functions such as thought and language. It is divided into 6-7 layers, with two main cell types: pyramidal cells and nonpyramidal cells. The surface of the neocortex is divided into separate areas, each given a number by Brodmann (e.g. Brodmann’s area 17 is the primary visual cortex). The surface is folded to increase surface area, with grooves called sulci and ridges called gyri. The neocortex is responsible for higher cognitive functions and is essential for human consciousness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 166 - How would you describe the condition of a patient who, after experiencing a...

    Incorrect

    • How would you describe the condition of a patient who, after experiencing a stroke, is unable to identify familiar objects despite having no sensory impairment?

      Your Answer:

      Correct Answer: Visual agnosia

      Explanation:

      Visual Agnosia: Inability to Recognize Familiar Objects

      Visual agnosia is a neurological condition that affects a person’s ability to recognize familiar objects, even though their sensory apparatus is functioning normally. This disorder can be further classified into different subtypes, with two of the most important being prosopagnosia and simultanagnosia.

      Prosopagnosia is the inability to identify faces, which can make it difficult for individuals to recognize family members, friends, of even themselves in a mirror. Simultanagnosia, on the other hand, is the inability to recognize a whole image, even though individual details may be recognized. This can make it challenging for individuals to understand complex scenes of navigate their environment.

      Visual agnosia can be caused by various factors, including brain damage from injury of disease. Treatment options for this condition are limited, but some individuals may benefit from visual aids of cognitive therapy to improve their ability to recognize objects.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 167 - What are the consequences of damage to the arcuate fasciculus? ...

    Incorrect

    • What are the consequences of damage to the arcuate fasciculus?

      Your Answer:

      Correct Answer: Conduction aphasia

      Explanation:

      Aphasia is a language impairment that affects the production of comprehension of speech, as well as the ability to read of write. The areas involved in language are situated around the Sylvian fissure, referred to as the ‘perisylvian language area’. For repetition, the primary auditory cortex, Wernicke, Broca via the Arcuate fasciculus (AF), Broca recodes into articulatory plan, primary motor cortex, and pyramidal system to cranial nerves are involved. For oral reading, the visual cortex to Wernicke and the same processes as for repetition follows. For writing, Wernicke via AF to premotor cortex for arm and hand, movement planned, sent to motor cortex. The classification of aphasia is complex and imprecise, with the Boston Group classification and Luria’s aphasia interpretation being the most influential. The important subtypes of aphasia include global aphasia, Broca’s aphasia, Wernicke’s aphasia, conduction aphasia, anomic aphasia, transcortical motor aphasia, and transcortical sensory aphasia. Additional syndromes include alexia without agraphia, alexia with agraphia, and pure word deafness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 168 - In what type of epilepsy is it most common to experience an aura?...

    Incorrect

    • In what type of epilepsy is it most common to experience an aura?

      Your Answer:

      Correct Answer: Complex partial

      Explanation:

      This question is presented in two variations on the exam, with one implying that auras are primarily linked to temporal lobe epilepsy and the other to complex partial seizures. In reality, partial seizures are most commonly associated with auras compared to other types of seizures. While partial seizures can originate in any lobe of the brain, those that arise in the temporal lobe are most likely to produce an aura. Therefore, both versions of the question are accurate.

      Epilepsy and Aura

      An aura is a subjective sensation that is a type of simple partial seizure. It typically lasts only a few seconds and can help identify the site of cortical onset. There are eight recognized types of auras, including somatosensory, visual, auditory, gustatory, olfactory, autonomic, abdominal, and psychic.

      In about 80% of cases, auras precede temporal lobe seizures. The most common auras in these seizures are abdominal and psychic, which can cause a rising epigastric sensation of feelings of fear, déjà vu, of jamais vu. Parietal lobe seizures may begin with a contralateral sensation, usually of the positive type, such as an electrical sensation of tingling. Occipital lobe seizures may begin with contralateral visual changes, such as colored lines, spots, of shapes, of even a loss of vision. Temporal-parietal-occipital seizures may produce more formed auras.

      Complex partial seizures are defined by impairment of consciousness, which means decreased responsiveness and awareness of oneself and surroundings. During a complex partial seizure, a patient is unresponsive and does not remember events that occurred.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 169 - What is a true statement about the cingulate gyrus? ...

    Incorrect

    • What is a true statement about the cingulate gyrus?

      Your Answer:

      Correct Answer: It is involved in reward-based decision making

      Explanation:

      The fusiform gyrus is essential for recognizing faces and bodies, while damage to the angular gyrus can result in Gerstmann syndrome.

      The Cingulate Gyrus: A Hub for Emotions and Decision Making

      The cingulate gyrus is a cortical fold located on the medial aspect of the cerebral hemisphere, adjacent to the corpus callosum. As part of the limbic system, it plays a crucial role in processing emotions and regulating the body’s endocrine and autonomic responses to emotional stimuli. Additionally, it is involved in reward-based decision making. Essentially, the cingulate gyrus acts as a hub that connects emotions, sensations, and actions. The term cingulate comes from the Latin word for belt of girdle, which reflects the way in which it wraps around the corpus callosum.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 170 - From which amino acid is serotonin synthesized? ...

    Incorrect

    • From which amino acid is serotonin synthesized?

      Your Answer:

      Correct Answer: Tryptophan

      Explanation:

      Serotonin: Synthesis and Breakdown

      Serotonin, also known as 5-Hydroxytryptamine (5-HT), is synthesized in the central nervous system (CNS) in the raphe nuclei located in the brainstem, as well as in the gastrointestinal (GI) tract in enterochromaffin cells. The amino acid L-tryptophan, obtained from the diet, is used to synthesize serotonin. L-tryptophan can cross the blood-brain barrier, but serotonin cannot.

      The transformation of L-tryptophan into serotonin involves two steps. First, hydroxylation to 5-hydroxytryptophan is catalyzed by tryptophan hydroxylase. Second, decarboxylation of 5-hydroxytryptophan to serotonin (5-hydroxytryptamine) is catalyzed by L-aromatic amino acid decarboxylase.

      Serotonin is taken up from the synapse by a monoamine transporter (SERT). Substances that block this transporter include MDMA, amphetamine, cocaine, TCAs, and SSRIs. Serotonin is broken down by monoamine oxidase (MAO) and then by aldehyde dehydrogenase to 5-Hydroxyindoleacetic acid (5-HIAA).

    • This question is part of the following fields:

      • Neurosciences
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  • Question 171 - Where do macroscopic abnormalities typically appear in the brains of individuals with dyslexia?...

    Incorrect

    • Where do macroscopic abnormalities typically appear in the brains of individuals with dyslexia?

      Your Answer:

      Correct Answer: Planum temporale

      Explanation:

      Brain Abnormalities in Dyslexia

      Individuals with dyslexia often exhibit a loss of the typical left-right asymmetry at the planum temporale in the temporal lobe. However, this abnormality can also be observed in the brains of individuals without dyslexia, making it a sensitive but not specific marker for the disorder. None of the other brain regions mentioned are associated with dyslexia. The pineal gland, located in the epithalamus, secretes melatonin. The third interstitial nucleus of the anterior hypothalamus is larger in heterosexual men compared to homosexual men and heterosexual women. The medulla oblongata is located in the brainstem, and the lateral geniculate nucleus in the thalamus relays visual information from the retina to the occipital cortex.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 172 - What is a true statement about GABA? ...

    Incorrect

    • What is a true statement about GABA?

      Your Answer:

      Correct Answer: Flumazenil is a GABA-A antagonist

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 173 - What is the primary component of alpha-synuclein? ...

    Incorrect

    • What is the primary component of alpha-synuclein?

      Your Answer:

      Correct Answer: Lewy bodies

      Explanation:

      Lewy body dementia is a neurodegenerative disorder that is characterized by both macroscopic and microscopic changes in the brain. Macroscopically, there is cerebral atrophy, but it is less marked than in Alzheimer’s disease, and the brain weight is usually in the normal range. There is also pallor of the substantia nigra and the locus coeruleus, which are regions of the brain that produce dopamine and norepinephrine, respectively.

      Microscopically, Lewy body dementia is characterized by the presence of intracellular protein accumulations called Lewy bodies. The major component of a Lewy body is alpha synuclein, and as they grow, they start to draw in other proteins such as ubiquitin. Lewy bodies are also found in Alzheimer’s disease, but they tend to be in the amygdala. They can also be found in healthy individuals, although it has been suggested that these may be pre-clinical cases of dementia with Lewy bodies. Lewy bodies are also found in other neurodegenerative disorders such as progressive supranuclear palsy, corticobasal degeneration, and multiple system atrophy.

      In Lewy body dementia, Lewy bodies are mainly found within the brainstem, but they are also found in non-brainstem regions such as the amygdaloid nucleus, parahippocampal gyrus, cingulate cortex, and cerebral neocortex. Classic brainstem Lewy bodies are spherical intraneuronal cytoplasmic inclusions, characterized by hyaline eosinophilic cores, concentric lamellar bands, narrow pale halos, and immunoreactivity for alpha synuclein and ubiquitin. In contrast, cortical Lewy bodies typically lack a halo.

      Most brains with Lewy body dementia also show some plaques and tangles, although in most instances, the lesions are not nearly as severe as in Alzheimer’s disease. Neuronal loss and gliosis are usually restricted to brainstem regions, particularly the substantia nigra and locus ceruleus.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 174 - Which inhibitory neurotransmitter's receptor is blocked by strychnine, resulting in strychnine poisoning? ...

    Incorrect

    • Which inhibitory neurotransmitter's receptor is blocked by strychnine, resulting in strychnine poisoning?

      Your Answer:

      Correct Answer: Glycine

      Explanation:

      The primary neurotransmitters that promote neural activity are glutamate and aspartate, while the primary neurotransmitters that inhibit neural activity are GABA and glycine.

      Glycine and its Antagonist Strychnine

      Glycine is a neurotransmitter that binds to a receptor, which increases the permeability of the postsynaptic membrane to chloride ions. This results in hyperpolarization of the membrane, making it less likely to depolarize and thus, glycine acts as an inhibitory neurotransmitter.

      On the other hand, strychnine is a glycine antagonist that can bind to the glycine receptor without opening the chloride ion-channel. This inhibition of inhibition leads to spinal hyperexcitability, which is why strychnine is a poison. The binding of strychnine to the glycine receptor prevents glycine from performing its inhibitory function, leading to an increase in the likelihood of depolarization and causing hyperexcitability. Therefore, the effects of glycine and strychnine on the glycine receptor are opposite, with glycine acting as an inhibitor and strychnine acting as an excitatory agent.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 175 - Which receptors are affected by fluoxetine that are believed to be responsible for...

    Incorrect

    • Which receptors are affected by fluoxetine that are believed to be responsible for causing insomnia?

      Your Answer:

      Correct Answer: 5-HT2

      Explanation:

      Serotonin (5-hydroxytryptamine, 5-HT) receptors are primarily G protein receptors, except for 5-HT3, which is a ligand-gated receptor. It is important to remember that 5-HT3 is most commonly associated with nausea. Additionally, 5-HT7 is linked to circadian rhythms. The stimulation of 5-HT2 receptors is believed to be responsible for the side effects of insomnia, agitation, and sexual dysfunction that are associated with the use of selective serotonin reuptake inhibitors (SSRIs).

    • This question is part of the following fields:

      • Neurosciences
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  • Question 176 - What is the entity responsible for producing myelin in the central nervous system?...

    Incorrect

    • What is the entity responsible for producing myelin in the central nervous system?

      Your Answer:

      Correct Answer: Oligodendrocyte

      Explanation:

      Glial Cells: The Support System of the Central Nervous System

      The central nervous system is composed of two basic cell types: neurons and glial cells. Glial cells, also known as support cells, play a crucial role in maintaining the health and function of neurons. There are several types of glial cells, including macroglia (astrocytes and oligodendrocytes), ependymal cells, and microglia.

      Astrocytes are the most abundant type of glial cell and have numerous functions, such as providing structural support, repairing nervous tissue, nourishing neurons, contributing to the blood-brain barrier, and regulating neurotransmission and blood flow. There are two main types of astrocytes: protoplasmic and fibrous.

      Oligodendrocytes are responsible for the formation of myelin sheaths, which insulate and protect axons, allowing for faster and more efficient transmission of nerve impulses.

      Ependymal cells line the ventricular system and are involved in the circulation of cerebrospinal fluid (CSF) and fluid homeostasis in the brain. Specialized ependymal cells called choroid plexus cells produce CSF.

      Microglia are the immune cells of the CNS and play a crucial role in protecting the brain from infection and injury. They also contribute to the maintenance of neuronal health and function.

      In summary, glial cells are essential for the proper functioning of the central nervous system. They provide structural support, nourishment, insulation, and immune defense to neurons, ensuring the health and well-being of the brain and spinal cord.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 177 - What is believed to be the cause of the negative symptoms observed in...

    Incorrect

    • What is believed to be the cause of the negative symptoms observed in individuals with schizophrenia?

      Your Answer:

      Correct Answer: Decreased dopaminergic activity in the frontal lobe

      Explanation:

      Psychosis is associated with heightened dopaminergic activity in the striatum, while negative symptoms are linked to reduced dopaminergic activity in the frontal lobe.

      The Dopamine Hypothesis is a theory that suggests that dopamine and dopaminergic mechanisms are central to schizophrenia. This hypothesis was developed based on observations that antipsychotic drugs provide at least some degree of D2-type dopamine receptor blockade and that it is possible to induce a psychotic episode in healthy subjects with pharmacological dopamine agonists. The hypothesis was further strengthened by the finding that antipsychotic drugs’ clinical effectiveness was directly related to their affinity for dopamine receptors. Initially, the belief was that the problem related to an excess of dopamine in the brain. However, later studies showed that the relationship between hypofrontality and low cerebrospinal fluid (CSF) dopamine metabolite levels indicates low frontal dopamine levels. Thus, there was a move from a one-sided dopamine hypothesis explaining all facets of schizophrenia to a regionally specific prefrontal hypodopaminergia and a subcortical hyperdopaminergia. In summary, psychosis appears to result from excessive dopamine activity in the striatum, while the negative symptoms seen in schizophrenia appear to result from too little dopamine activity in the frontal lobe. Antipsychotic medications appear to help by countering the effects of increased dopamine by blocking postsynaptic D2 receptors in the striatum.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 178 - Which of the following is an amino acid neurotransmitter? ...

    Incorrect

    • Which of the following is an amino acid neurotransmitter?

      Your Answer:

      Correct Answer: Gamma-aminobutyric acid (GABA)

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 179 - What is the primary component of Hirano bodies? ...

    Incorrect

    • What is the primary component of Hirano bodies?

      Your Answer:

      Correct Answer: Actin

      Explanation:

      Actin is the primary component of Hirano bodies, which are indicative of neurodegeneration but lack specificity.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 180 - What is a true statement about the planum temporale? ...

    Incorrect

    • What is a true statement about the planum temporale?

      Your Answer:

      Correct Answer: It consists of secondary auditory cortex

      Explanation:

      Cerebral Asymmetry in Planum Temporale and its Implications in Language and Auditory Processing

      The planum temporale, a triangular region in the posterior superior temporal gyrus, is a highly lateralized brain structure involved in language and music processing. Studies have shown that the planum temporale is up to ten times larger in the left cerebral hemisphere than the right, with this asymmetry being more prominent in men. This asymmetry can be observed in gestation and is present in up to 70% of right-handed individuals.

      Recent research suggests that the planum temporale also plays an important role in auditory processing, specifically in representing the location of sounds in space. However, reduced planum temporale asymmetry has been observed in individuals with dyslexia, stuttering, and schizophrenia. These findings highlight the importance of cerebral asymmetry in the planum temporale and its implications in language and auditory processing.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 181 - Which one of these pathways is not associated with dopamine? ...

    Incorrect

    • Which one of these pathways is not associated with dopamine?

      Your Answer:

      Correct Answer: Limbostriatal pathway

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 182 - Which structure is most likely to show signs of atrophy in a patient...

    Incorrect

    • Which structure is most likely to show signs of atrophy in a patient with Alzheimer's disease?

      Your Answer:

      Correct Answer: Hippocampus

      Explanation:

      Alzheimer’s disease often results in the shrinkage of the hippocampus, which is a component of the limbic system and is responsible for the formation and retention of long-term memories.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 183 - What condition is most commonly associated with slow (<2.5 Hz) generalized spike-and-wave discharges...

    Incorrect

    • What condition is most commonly associated with slow (<2.5 Hz) generalized spike-and-wave discharges on the EEG?

      Your Answer:

      Correct Answer: Atypical absence seizures

      Explanation:

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 184 - What is a true statement about Lewy bodies? ...

    Incorrect

    • What is a true statement about Lewy bodies?

      Your Answer:

      Correct Answer: Cortical Lewy bodies typically lack a halo on staining

      Explanation:

      The absence of a halo distinguishes the Lewy bodies found in the brainstem from those found in the cortex. These bodies consist of alpha-synuclein protein, along with other proteins like ubiquitin, neurofilament protein, and alpha B crystallin. Additionally, they may contain tau proteins and are sometimes encircled by neurofibrillary tangles.

      Lewy body dementia is a neurodegenerative disorder that is characterized by both macroscopic and microscopic changes in the brain. Macroscopically, there is cerebral atrophy, but it is less marked than in Alzheimer’s disease, and the brain weight is usually in the normal range. There is also pallor of the substantia nigra and the locus coeruleus, which are regions of the brain that produce dopamine and norepinephrine, respectively.

      Microscopically, Lewy body dementia is characterized by the presence of intracellular protein accumulations called Lewy bodies. The major component of a Lewy body is alpha synuclein, and as they grow, they start to draw in other proteins such as ubiquitin. Lewy bodies are also found in Alzheimer’s disease, but they tend to be in the amygdala. They can also be found in healthy individuals, although it has been suggested that these may be pre-clinical cases of dementia with Lewy bodies. Lewy bodies are also found in other neurodegenerative disorders such as progressive supranuclear palsy, corticobasal degeneration, and multiple system atrophy.

      In Lewy body dementia, Lewy bodies are mainly found within the brainstem, but they are also found in non-brainstem regions such as the amygdaloid nucleus, parahippocampal gyrus, cingulate cortex, and cerebral neocortex. Classic brainstem Lewy bodies are spherical intraneuronal cytoplasmic inclusions, characterized by hyaline eosinophilic cores, concentric lamellar bands, narrow pale halos, and immunoreactivity for alpha synuclein and ubiquitin. In contrast, cortical Lewy bodies typically lack a halo.

      Most brains with Lewy body dementia also show some plaques and tangles, although in most instances, the lesions are not nearly as severe as in Alzheimer’s disease. Neuronal loss and gliosis are usually restricted to brainstem regions, particularly the substantia nigra and locus ceruleus.

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      • Neurosciences
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  • Question 185 - A 60-year-old patient complains of headaches which are worse in the morning and...

    Incorrect

    • A 60-year-old patient complains of headaches which are worse in the morning and have been present for 2 months. They have been told by their GP it is probably 'tension headache'. Which of the following symptoms is suggestive of a more sinister pathology?

      Your Answer:

      Correct Answer: Pain worse on bending down

      Explanation:

      Indicators of a potentially serious headache are:

      – Developing a headache for the first time after the age of 50
      – Sudden and severe headache (often described as a thunderclap headache)
      – Accompanying symptoms such as redness in the eye and seeing halos around lights
      – Headache that gets worse with physical activity of straining (such as during a Valsalva maneuver)

      Cerebral Tumours

      The most common brain tumours in adults, listed in order of frequency, are metastatic tumours, glioblastoma multiforme, anaplastic astrocytoma, and meningioma. On the other hand, the most common brain tumours in children, listed in order of frequency, are astrocytoma, medulloblastoma, and ependymoma.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 186 - A 40 year old female is admitted to the ward with a diagnosis...

    Incorrect

    • A 40 year old female is admitted to the ward with a diagnosis of depression. On admission the doctor notes skin changes consistent with erythema nodosum and also notes that the patient complains of being short of breath. Unfortunately the lady commits suicide shortly after admission. A post-mortem biopsy reveals Asteroid bodies. Which of the following diagnosis would you most suspect?:

      Your Answer:

      Correct Answer: Sarcoidosis

      Explanation:

      Pathology Findings in Psychiatry

      There are several pathology findings that are associated with various psychiatric conditions. Papp-Lantos bodies, for example, are visible in the CNS and are associated with multisystem atrophy. Pick bodies, on the other hand, are large, dark-staining aggregates of proteins in neurological tissue and are associated with frontotemporal dementia.

      Lewy bodies are another common pathology finding in psychiatry and are associated with Parkinson’s disease and Lewy Body dementia. These are round, concentrically laminated, pale eosinophilic cytoplasmic inclusions that are aggregates of alpha-synuclein.

      Other pathology findings include asteroid bodies, which are associated with sarcoidosis and berylliosis, and are acidophilic, stellate inclusions in giant cells. Barr bodies are associated with stains of X chromosomes and are inactivated X chromosomes that appear as a dark staining mass in contact with the nuclear membrane.

      Mallory bodies are another common pathology finding and are associated with alcoholic hepatitis, alcoholic cirrhosis, Wilson’s disease, and primary-biliary cirrhosis. These are eosinophilic intracytoplasmic inclusions in hepatocytes that are made up of intermediate filaments, predominantly prekeratin.

      Other pathology findings include Schaumann bodies, which are associated with sarcoidosis and berylliosis, and are concentrically laminated inclusions in giant cells. Zebra bodies are associated with Niemann-Pick disease, Tay-Sachs disease, of any of the mucopolysaccharidoses and are palisaded lamellated membranous cytoplasmic bodies seen in macrophages.

      LE bodies, also known as hematoxylin bodies, are associated with SLE (lupus) and are nuclei of damaged cells with bound anti-nuclear antibodies that become homogeneous and loose chromatin pattern. Verocay bodies are associated with Schwannoma (Neurilemoma) and are palisades of nuclei at the end of a fibrillar bundle.

      Hirano bodies are associated with normal aging but are more numerous in Alzheimer’s disease. These are eosinophilic, football-shaped inclusions seen in neurons of the brain. Neurofibrillary tangles are another common pathology finding in Alzheimer’s disease and are made up of microtubule-associated proteins and neurofilaments.

      Kayser-Fleischer rings are associated with Wilson’s disease and are rings of discoloration on the cornea. Finally, Kuru plaques are associated with Kuru and Gerstmann-Sträussler syndrome and are sometimes present in patients with Creutzfeldt-Jakob disease (CJD). These are composed partly of a host-encoded prion protein.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 187 - What triggers the release of neurotransmitter from presynaptic vesicles into the synaptic cleft?...

    Incorrect

    • What triggers the release of neurotransmitter from presynaptic vesicles into the synaptic cleft?

      Your Answer:

      Correct Answer: Calcium

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 188 - A 35 year old woman has been referred to your clinic with suspected...

    Incorrect

    • A 35 year old woman has been referred to your clinic with suspected functional paralysis of the left leg. When you ask her to raise her unaffected leg while lying flat on the bed, you feel her pushing down on your hand as you place it under her affected leg.
      What sign has been demonstrated?

      Your Answer:

      Correct Answer: Hoover's sign

      Explanation:

      – A Battle’s sign is a physical indication of a basal skull fracture.
      – Babinski’s sign is a clinical sign that suggests an upper motor neuron lesion.
      – Kernig’s sign is a clinical sign that indicates meningeal irritation.
      – Russell’s sign is characterized by scarring on the knuckles and back of the hand, and it is indicative of repeated induced vomiting.

      Hoover’s Sign for Differentiating Organic and Functional Weakness

      Functional weakness refers to weakness that is inconsistent with any identifiable neurological disease and may be diagnosed as conversion disorder of dissociative motor disorder. To differentiate between organic and functional weakness of pyramidal origin, Dr. Charles Franklin Hoover described Hoover’s sign over 100 years ago.

      This test is typically performed on the lower limbs and is useful when the nature of hemiparesis is uncertain. When a person with organic hemiparesis is asked to flex the hip of their normal leg against resistance, they will not exert pressure on the examiner’s hand placed under the heel on the affected side. However, in hysterical weakness, the examiner will feel increased pressure on their hand. Hoover’s sign is a valuable tool for distinguishing between organic and functional weakness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 189 - Which symptom would indicate a hydrocephalus that is communicating rather than non-communicating? ...

    Incorrect

    • Which symptom would indicate a hydrocephalus that is communicating rather than non-communicating?

      Your Answer:

      Correct Answer: Ataxia

      Explanation:

      Normal Pressure Hydrocephalus

      Normal pressure hydrocephalus is a type of chronic communicating hydrocephalus, which occurs due to the impaired reabsorption of cerebrospinal fluid (CSF) by the arachnoid villi. Although the CSF pressure is typically high, it remains within the normal range, and therefore, it does not cause symptoms of high intracranial pressure (ICP) such as headache and nausea. Instead, patients with normal pressure hydrocephalus usually present with a classic triad of symptoms, including incontinence, gait ataxia, and dementia, which is often referred to as wet, wobbly, and wacky. Unfortunately, this condition is often misdiagnosed as Parkinson’s of Alzheimer’s disease.

      The classic triad of normal pressure hydrocephalus, also known as Hakim’s triad, includes gait instability, urinary incontinence, and dementia. On the other hand, non-communicating hydrocephalus results from the obstruction of CSF flow in the third of fourth ventricle, which causes symptoms of raised intracranial pressure, such as headache, vomiting, hypertension, bradycardia, altered consciousness, and papilledema.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 190 - What is the main component of pick bodies? ...

    Incorrect

    • What is the main component of pick bodies?

      Your Answer:

      Correct Answer: Tau

      Explanation:

      Pyramidal cell neurons known as Betz cells are situated in the grey matter of the motor cortex.

      Frontotemporal Lobar Degeneration (FTLD) is a pathological term that refers to a group of neurodegenerative disorders that affect the frontal and temporal lobes of the brain. FTLD is classified into several subtypes based on the main protein component of neuronal and glial abnormal inclusions and their distribution. The three main proteins associated with FTLD are Tau, TDP-43, and FUS. Each FTD clinical phenotype has been associated with different proportions of these proteins. Macroscopic changes in FTLD include atrophy of the frontal and temporal lobes, with focal gyral atrophy that resembles knives. Microscopic changes in FTLD-Tau include neuronal and glial tau aggregation, with further sub-classification based on the existence of different isoforms of tau protein. FTLD-TDP is characterized by cytoplasmic inclusions of TDP-43 in neurons, while FTLD-FUS is characterized by cytoplasmic inclusions of FUS.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 191 - Which type of axon is responsible for the intense and sudden pain experienced...

    Incorrect

    • Which type of axon is responsible for the intense and sudden pain experienced during an injury?

      Your Answer:

      Correct Answer: A-delta

      Explanation:

      Primary Afferent Axons: Conveying Information about Touch and Pain

      Primary afferent axons play a crucial role in conveying information about touch and pain from the surface of the body to the spinal cord and brain. These axons can be classified into four types based on their functions: A-alpha (proprioception), A-beta (touch), A-delta (pain and temperature), and C (pain, temperature, and itch). While all A axons are myelinated, C fibers are unmyelinated.

      A-delta fibers are responsible for the sharp initial pain, while C fibers are responsible for the slow, dull, longer-lasting second pain. Understanding the different types of primary afferent axons and their functions is essential in diagnosing and treating various sensory disorders.

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      • Neurosciences
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  • Question 192 - What is the neurotransmitter that prevents the pituitary gland from releasing prolactin? ...

    Incorrect

    • What is the neurotransmitter that prevents the pituitary gland from releasing prolactin?

      Your Answer:

      Correct Answer: Dopamine

      Explanation:

      Hormones and their functions:

      Dopamine, also known as prolactin inhibitory factor, is released from the hypothalamus. Antipsychotics, which are dopamine antagonists, are often linked to increased prolactin levels.

      Oxytocin, released from the posterior pituitary, plays a crucial role in sexual reproduction.

      Substance P is present throughout the brain and is essential in pain perception.

      Vasopressin, a peptide hormone, is released from the posterior pituitary.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 193 - What are some common symptoms that are typically observed in the initial phases...

    Incorrect

    • What are some common symptoms that are typically observed in the initial phases of Alzheimer's disease?

      Your Answer:

      Correct Answer: Hippocampal atrophy

      Explanation:

      The medial temporal lobe, comprising the hippocampus and parahippocampal gyrus, exhibits the earliest neuropathological alterations.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 194 - What is the typical artery that is blocked in cases of Alexia without...

    Incorrect

    • What is the typical artery that is blocked in cases of Alexia without agraphia?

      Your Answer:

      Correct Answer: Posterior cerebral artery

      Explanation:

      Aphasia is a language impairment that affects the production of comprehension of speech, as well as the ability to read of write. The areas involved in language are situated around the Sylvian fissure, referred to as the ‘perisylvian language area’. For repetition, the primary auditory cortex, Wernicke, Broca via the Arcuate fasciculus (AF), Broca recodes into articulatory plan, primary motor cortex, and pyramidal system to cranial nerves are involved. For oral reading, the visual cortex to Wernicke and the same processes as for repetition follows. For writing, Wernicke via AF to premotor cortex for arm and hand, movement planned, sent to motor cortex. The classification of aphasia is complex and imprecise, with the Boston Group classification and Luria’s aphasia interpretation being the most influential. The important subtypes of aphasia include global aphasia, Broca’s aphasia, Wernicke’s aphasia, conduction aphasia, anomic aphasia, transcortical motor aphasia, and transcortical sensory aphasia. Additional syndromes include alexia without agraphia, alexia with agraphia, and pure word deafness.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 195 - In which part of the body is the nucleus of Meynert situated? ...

    Incorrect

    • In which part of the body is the nucleus of Meynert situated?

      Your Answer:

      Correct Answer: Substantia innominata

      Explanation:

      The nucleus of Meynert, located in the substantia innominata of the basal forebrain beneath the thalamus and lentiform nucleus, is a cluster of neurons that serves as the primary source of acetylcholine in the brain. In Alzheimer’s disease, the nucleus of Meynert undergoes atrophy, resulting in a decrease in acetylcholine levels. This explains why cholinesterase inhibitors, which increase acetylcholine levels, are effective in treating Alzheimer’s.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 196 - Who received the Nobel prize for their discovery of dopamine's function as a...

    Incorrect

    • Who received the Nobel prize for their discovery of dopamine's function as a neurotransmitter?

      Your Answer:

      Correct Answer: Carlsson

      Explanation:

      Neurotransmitters are substances used by neurons to communicate with each other and with target tissues. They are synthesized and released from nerve endings into the synaptic cleft, where they bind to receptor proteins in the cellular membrane of the target tissue. Neurotransmitters can be classified into different types, including small molecules (such as acetylcholine, dopamine, norepinephrine, serotonin, and GABA) and large molecules (such as neuropeptides). They can also be classified as excitatory or inhibitory. Receptors can be ionotropic or metabotropic, and the effects of neurotransmitters can be fast of slow. Some important neurotransmitters include acetylcholine, dopamine, GABA, norepinephrine, and serotonin. Each neurotransmitter has a specific synthesis, breakdown, and receptor type. Understanding neurotransmitters is important for understanding the function of the nervous system and for developing treatments for neurological and psychiatric disorders.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 197 - What are some common symptoms that are typically observed in the initial phases...

    Incorrect

    • What are some common symptoms that are typically observed in the initial phases of Alzheimer's disease?

      Your Answer:

      Correct Answer: Hippocampal atrophy

      Explanation:

      The medial temporal lobe, comprising the hippocampus and parahippocampal gyrus, exhibits the earliest neuropathological alterations.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 198 - What are the roles of purposes of the amygdala? ...

    Incorrect

    • What are the roles of purposes of the amygdala?

      Your Answer:

      Correct Answer: All of the above

      Explanation:

      The Amygdala: A Key Player in Emotional Processing

      The amygdala is a small, almond-shaped structure located in the anterior temporal lobe of the brain. As a core component of the limbic system, it plays a crucial role in emotional processing and regulation.

      To better understand its function, we can use the metaphor of a car being driven on the road. The frontal lobe of the brain acts as the driver, making decisions and navigating the environment. The amygdala, on the other hand, serves as the dashboard, providing the driver with important information about the car’s status, such as temperature and fuel levels. In this way, the amygdala gives emotional meaning to sensory input, allowing us to respond appropriately to potential threats of opportunities.

      One of the amygdala’s primary functions is to activate the fight or flight response in response to perceived danger. It does this by sending signals to the hypothalamus, which in turn triggers the release of stress hormones like adrenaline and cortisol. This prepares the body to either confront the threat of flee from it.

      In addition to its role in the fight or flight response, the amygdala also plays a role in regulating appetite and eating behavior. Studies have shown that damage to the amygdala can lead to overeating and obesity, suggesting that it may be involved in the hypothalamic control of feeding behavior.

      Overall, the amygdala is a key player in emotional processing and regulation, helping us to respond appropriately to the world around us.

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      • Neurosciences
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  • Question 199 - With what condition of disease are Hirano bodies commonly linked? ...

    Incorrect

    • With what condition of disease are Hirano bodies commonly linked?

      Your Answer:

      Correct Answer: Alzheimer's

      Explanation:

      Hirano bodies are considered to be a general indication of neuronal degeneration and are primarily observed in cases of Alzheimer’s disease.

      Alzheimer’s disease is characterized by both macroscopic and microscopic changes in the brain. Macroscopic changes include cortical atrophy, ventricular dilation, and depigmentation of the locus coeruleus. Microscopic changes include the presence of senile plaques, neurofibrillary tangles, gliosis, degeneration of the nucleus of Meynert, and Hirano bodies. Senile plaques are extracellular deposits of beta amyloid in the gray matter of the brain, while neurofibrillary tangles are intracellular inclusion bodies that consist primarily of hyperphosphorylated tau. Gliosis is marked by increases in activated microglia and reactive astrocytes near the sites of amyloid plaques. The nucleus of Meynert degenerates in Alzheimer’s, resulting in a decrease in acetylcholine in the brain. Hirano bodies are actin-rich, eosinophilic intracytoplasmic inclusions which have a highly characteristic crystalloid fine structure and are regarded as a nonspecific manifestation of neuronal degeneration. These changes in the brain contribute to the cognitive decline and memory loss seen in Alzheimer’s disease.

    • This question is part of the following fields:

      • Neurosciences
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  • Question 200 - What EEG alteration would be anticipated when a patient who is in a...

    Incorrect

    • What EEG alteration would be anticipated when a patient who is in a relaxed state with their eyes shut is instructed to open their eyes and read a text passage in front of them?

      Your Answer:

      Correct Answer: The bilateral disappearance of alpha waves

      Explanation:

      When someone is in a relaxed state with their eyes closed, alpha waves can be detected in the posterior regions of their head. However, these waves will disappear if the person becomes drowsy, concentrates on something, is stimulated, of fixates on a visual object. If the environment is dark, the alpha waves may still be present even with the eyes open.

      Electroencephalography

      Electroencephalography (EEG) is a clinical test that records the brain’s spontaneous electrical activity over a short period of time using multiple electrodes placed on the scalp. It is mainly used to rule out organic conditions and can help differentiate dementia from other disorders such as metabolic encephalopathies, CJD, herpes encephalitis, and non-convulsive status epilepticus. EEG can also distinguish possible psychotic episodes and acute confusional states from non-convulsive status epilepticus.

      Not all abnormal EEGs represent an underlying condition, and psychotropic medications can affect EEG findings. EEG abnormalities can also be triggered purposely by activation procedures such as hyperventilation, photic stimulation, certain drugs, and sleep deprivation.

      Specific waveforms are seen in an EEG, including delta, theta, alpha, sigma, beta, and gamma waves. Delta waves are found frontally in adults and posteriorly in children during slow wave sleep, and excessive amounts when awake may indicate pathology. Theta waves are generally seen in young children, drowsy and sleeping adults, and during meditation. Alpha waves are seen posteriorly when relaxed and when the eyes are closed, and are also seen in meditation. Sigma waves are bursts of oscillatory activity that occur in stage 2 sleep. Beta waves are seen frontally when busy of concentrating, and gamma waves are seen in advanced/very experienced meditators.

      Certain conditions are associated with specific EEG changes, such as nonspecific slowing in early CJD, low voltage EEG in Huntington’s, diffuse slowing in encephalopathy, and reduced alpha and beta with increased delta and theta in Alzheimer’s.

      Common epileptiform patterns include spikes, spike/sharp waves, and spike-waves. Medications can have important effects on EEG findings, with clozapine decreasing alpha and increasing delta and theta, lithium increasing all waveforms, lamotrigine decreasing all waveforms, and valproate having inconclusive effects on delta and theta and increasing beta.

      Overall, EEG is a useful tool in clinical contexts for ruling out organic conditions and differentiating between various disorders.

    • This question is part of the following fields:

      • Neurosciences
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