The tuberoinfundibular pathway links the hypothalamus with the pituitary gland, rather than the pineal gland.

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.

The distinguishing factors between the two are based on personal interpretation and tangible versus intangible concepts.

Altered Perceptual Experiences

Disorders of perception can be categorized into sensory distortions and sensory deceptions. Sensory distortions involve changes in the intensity, spatial form, of quality of a perception. Examples include hyperaesthesia, hyperacusis, and micropsia. Sensory deceptions, on the other hand, involve new perceptions that are not based on any external stimulus. These include illusions and hallucinations.

Illusions are altered perceptions of a stimulus, while hallucinations are perceptions in the absence of a stimulus. Completion illusions, affect illusions, and pareidolic illusions are examples of illusions. Auditory, visual, gustatory, olfactory, and tactile hallucinations are different types of hallucinations. Pseudohallucinations are involuntary and vivid sensory experiences that are interpreted in a non-morbid way. They are different from true hallucinations in that the individual is able to recognize that the experience is an internally generated event.

Understanding the different types of altered perceptual experiences is important in the diagnosis and treatment of various mental health conditions.

Hyperprolactinemia is a potential side effect of antipsychotic medication, but it is rare with antidepressants. Dopamine inhibits prolactin, so dopamine antagonists, such as antipsychotics, can increase prolactin levels. The degree of prolactin elevation is dose-related, and some antipsychotics cause more significant increases than others. Hyperprolactinemia can cause symptoms such as galactorrhea, menstrual difficulties, gynecomastia, hypogonadism, and sexual dysfunction. Long-standing hyperprolactinemia in psychiatric patients can increase the risk of osteoporosis and breast cancer, although there is no conclusive evidence that antipsychotic medication increases the risk of breast malignancy and mortality. Some antipsychotics, such as clozapine and aripiprazole, have a low risk of causing hyperprolactinemia, while typical antipsychotics and risperidone have a high risk. Monitoring of prolactin levels is recommended before starting antipsychotic therapy and at three months and annually thereafter. Antidepressants rarely cause hyperprolactinemia, and routine monitoring is not recommended. Symptomatic hyperprolactinemia has been reported with most antidepressants, except for a few, such as mirtazapine, agomelatine, bupropion, and vortioxetine.

Non-compliance is often caused by weight gain.

Antidepressants and Weight Gain

Studies suggest that certain types of antidepressants, such as tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs), may be more likely to cause weight gain than newer antidepressants like selective serotonin reuptake inhibitors (SSRIs). However, mirtazapine, a newer antidepressant, may have a similar risk for weight gain as TCAs. Among SSRIs, paroxetine may have a higher risk for weight gain during long-term treatment compared to other SSRIs. On the other hand, bupropion and nefazodone may have a lower risk for weight gain than SSRIs in the long term.

Karl Theodor Jaspers, a prominent German psychiatrist and philosopher, made significant contributions to modern psychiatry and philosophy. His book General Psychopathology, published in 1913, introduced many of the diagnostic criteria used today. Jaspers distinguished between primary delusions, which are inexplicable and sudden, and secondary delusions, which can be understood based on the patient’s internal and external environment. Other notable figures in the field include Eugen Bleuler, who coined the term schizophrenia, Emil Kraepelin, who introduced dementia praecox, and Kurt Schneider, who developed the first rank symptoms of schizophrenia.

Controversial studies in psychiatry have been a popular topic in exams. One such study was the Willowbrook School Study, where healthy children with learning difficulties were inoculated with hepatitis to assess the potential of gamma globulin to treat the disorder. Beecher’s study listed over 20 cases of mainstream research where subjects were experimented on without being fully informed of the risks. The Tuskegee syphilis experiment followed impoverished African-American sharecroppers with syphilis, and a significant proportion did not receive available treatment. Stanford’s prison experiment created a simulated prison environment where participants became their assigned roles, with guards becoming harsh and cruel to prisoners. The Tearooms Study involved Humphreys pretending to be a ‘watch queen’ to study men who have sex in public toilets, raising the issue of informed consent. Milgram’s Study investigated authority and obedience, where participants administered fake shocks to a confederate, with 30 participants continuing to administer shocks until 450 volts was reached. The Rosenhan experiment involved pseudopatients presenting themselves at institutions with the same symptoms and being admitted and diagnosed with serious mental disorders, leading to deinstitutionalisation.

Across all medical specialties, it is typical for patients to take less than half of their prescribed doses of self-administered medications, indicating low adherence rates that have been shown to be around 50%.

The observation that haloperidol, which has a high D2 occupancy, has a greater likelihood of causing EPSE, while clozapine, which has a lower D2 occupancy, has a lower risk, is in line with the research.

Extrapyramidal side-effects (EPSE’s) are a group of side effects that affect voluntary motor control, commonly seen in patients taking antipsychotic drugs. EPSE’s include dystonias, parkinsonism, akathisia, and tardive dyskinesia. They can be frightening and uncomfortable, leading to problems with non-compliance and can even be life-threatening in the case of laryngeal dystonia. EPSE’s are thought to be due to antagonism of dopaminergic D2 receptors in the basal ganglia. Symptoms generally occur within the first few days of treatment, with dystonias appearing quickly, within a few hours of administration of the first dose. Newer antipsychotics tend to produce less EPSE’s, with clozapine carrying the lowest risk and haloperidol carrying the highest risk. Akathisia is the most resistant EPSE to treat. EPSE’s can also occur when antipsychotics are discontinued (withdrawal dystonia).

The women’s shouting, which is an unpleasant stimulus, serves as a positive punisher that reduces the likelihood of the behavior (speeding) occurring again. This is distinct from reinforcement, which involves the introduction of a positive stimulus to increase the likelihood of a behavior being repeated.

Operant Conditioning: Reinforcement, Punishment, and More

Operant conditioning, also known as instrumental learning, is a theory of learning developed by B.F. Skinner. It suggests that people learn by interacting with their environment. Reinforcement and punishment are key concepts in operant conditioning. A reinforcer is a stimulus of event that increases the likelihood of a behavior being repeated. Reinforcement can be positive of negative. Positive reinforcement occurs when a behavior is strengthened by adding a rewarding stimulus, while negative reinforcement occurs when a behavior is strengthened by removing an unpleasant stimulus. A punisher is a stimulus that decreases the likelihood of a behavior being repeated. Positive punishment occurs when a behavior is reduced in frequency by adding an unpleasant stimulus, while negative punishment occurs when a behavior is reduced in frequency by removing a pleasant stimulus.

Primary reinforcers are instinctual desires such as food, water, social approval, and sex. Secondary reinforcers, also known as conditioned reinforcers, are not innately appreciated and people have to learn to like them through classical conditioning of other methods. Secondary reinforcers include things such as money. Different patterns of reinforcement have different influences on the response. There are five main reinforcement schedules: fixed interval, variable interval, fixed ratio, variable ratio, and random. Variable ratio schedules are most resistant to extinction.

Shaping and chaining are techniques used when an exact behavior cannot be performed and so cannot be rewarded. Shaping involves rewarding successive, increasingly accurate approximations to the behavior, while chaining involves breaking a complex task into smaller, more manageable sections. Escape conditioning refers to a situation whereby an aversive situation is removed after a response. It is a form of negative reinforcement. Habituation refers to the phenomenon whereby there is a decrease in response to a stimulus over time. Covert sensitization is a technique used whereby someone learns to use mental imagery to associate a behavior with a negative consequence.

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.

Extrapyramidal side-effects (EPSE’s) are a group of side effects that affect voluntary motor control, commonly seen in patients taking antipsychotic drugs. EPSE’s include dystonias, parkinsonism, akathisia, and tardive dyskinesia. They can be frightening and uncomfortable, leading to problems with non-compliance and can even be life-threatening in the case of laryngeal dystonia. EPSE’s are thought to be due to antagonism of dopaminergic D2 receptors in the basal ganglia. Symptoms generally occur within the first few days of treatment, with dystonias appearing quickly, within a few hours of administration of the first dose. Newer antipsychotics tend to produce less EPSE’s, with clozapine carrying the lowest risk and haloperidol carrying the highest risk. Akathisia is the most resistant EPSE to treat. EPSE’s can also occur when antipsychotics are discontinued (withdrawal dystonia).

Personality Disorder Classification

A personality disorder is a persistent pattern of behavior and inner experience that deviates significantly from cultural expectations, is inflexible and pervasive, and causes distress of impairment. The DSM-5 and ICD-11 have different approaches to classifying personality disorders. DSM-5 divides them into 10 categories, grouped into clusters A, B, and C, while ICD-11 has a general category with six trait domains that can be added. To diagnose a personality disorder, the general diagnostic threshold must be met before determining the subtype(s) present. The criteria for diagnosis include inflexibility and pervasiveness of the pattern, onset in adolescence of early adulthood, stability over time, and significant distress of impairment. The disturbance must not be better explained by another mental disorder, substance misuse, of medical condition.

Course

Borderline and antisocial personality disorders tend to become less evident of remit with age, while others, particularly obsessive-compulsive and schizotypal, may persist.

Classification

The DSM-5 divides personality disorders into separate clusters A, B, and C, with additional groups for medical conditions and unspecified disorders. The ICD-11 dropped the separate categories and instead lists six trait domains that can be added to the general diagnosis.

UK Epidemiology

The prevalence of personality disorders in Great Britain, according to the British National Survey of Psychiatric Morbidity, is 4.4%, with cluster C being the most common at 2.6%, followed by cluster A at 1.6% and cluster B at 1.2%. The most prevalent specific personality disorder is obsessive-compulsive (anankastic) at 1.9%.

OCD can trigger various defence mechanisms, such as repression, reaction formation, magical thinking, undoing, and isolation.

In a survey conducted by Nock et al.1, which involved interviewing more than 80,000 individuals across 17 countries, it was discovered that 9.2% of people have experienced suicidal thoughts at some point in their lives. Additionally, the survey found that 2.7% of individuals have attempted suicide, while 3.1% have made plans to do so.

In the given scenario, the individual is exhibiting projective identification by attributing their negative response to another person’s perceived attitudes. This is different from projection, where one attributes their own unacceptable thoughts of impulses to someone else.

The individual is not engaging in acting out, which involves impulsively acting on unconscious impulses to avoid conscious awareness of their effects. Instead, they are unable to gratify their impulse.

Suppression, a mature defense mechanism where one postpones attention to conscious impulses, is not being utilized in this situation. The individual is unable to avoid their unconscious impulse.

Repression involves the unconscious forgetting of painful memories of unacceptable impulses. However, in this scenario, the individual is expressing their unacceptable impulses rather than repressing them.

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.

Culture-bound syndromes are conditions that are specific to certain cultures and are often accompanied by culturally accepted beliefs and practices for treatment. These syndromes may not fit into the diagnostic criteria of Western medicine and are often unique to certain regions of ethnic groups. Examples of culture-bound syndromes include Taijin-jikoshu-kyofu in Japan, Piblokto in the Arctic, Koro in Malaysia, Locura among Latinos in the United States and Latin America, and Susto among Latinos in the United States and in Mexico, Central America, and South America. These syndromes are often associated with social and cultural factors and may require culturally sensitive approaches to treatment.

Holmes Rahe Stress Scale (Social Readjustment Rating Scale)

In 1967, Holmes and Rahe conducted a study on the impact of stress on illness. They surveyed over 5,000 medical patients and asked them to report whether they had experienced any of 43 life events in the past two years. Each event was assigned a Life Change Unit (LCU) value, which represented its weight for stress. The higher the score, the more likely the patient was to become ill.

The first 10 life events and their corresponding LCU values are listed below.

1. Death of spouse – 100
2. Divorce – 73
3. Marital separation – 65
4. Jail term – 63
5. Death of a close family member – 63
6. Personal illness – 53
7. Marriage – 50
8. Being fired from work – 47
9. Marital reconciliation – 45
10. Retirement – 45

This scale is known as the Holmes Rahe Stress Scale of the Social Readjustment Rating Scale. It is still widely used today to assess the impact of life events on stress levels and overall health.

Ishaq bin Ali Rahawi tackled ethical concerns in the field of medicine in his work, Adab al-Tabib (Conduct of a Physician), during the 9th century.

Ethical theory and principles are important in medical ethics. There are three key ethical theories that have dominated medical ethics: utilitarianism, deontological, and virtue-based. Utilitarianism is based on the greatest good for the greatest number and is a consequentialist theory. Deontological ethics emphasize moral duties and rules, rather than consequences. Virtue ethics is based on the ethical characteristics of a person and is associated with the concept of a good, happy, flourishing life.

More recent frameworks have attempted to reconcile different theories and values. The ‘four principles’ of ‘principlism’ approach, developed in the United States, is based on four common, basic prima facie moral commitments: autonomy, beneficence, non-maleficence, and justice. Autonomy refers to a patient’s right to make their own decisions, beneficence refers to the expectation that a doctor will act in a way that will be helpful to the patient, non-maleficence refers to the fact that doctors should avoid harming their patients, and justice refers to the expectation that all people should be treated fairly and equally.

Senile plaques and neurofibrillary tangles contain accumulations of hyperphosphorylated tau, while Hirano bodies are primarily composed of actin. The cytoskeleton is made up of microtubules (composed of tubulin), actin filaments, and intermediate filaments. Lewy bodies are characterized by the presence of insoluble aggregates of α-Synuclein, a protein that plays a role in regulating synaptic vesicle trafficking and neurotransmitter release.

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.

Common Motor Symptoms in Neurological Disorders

Perseveration is a symptom where an individual continues to use the same words of concepts even when they are no longer relevant. This is often seen in individuals with impaired consciousness due to acute of chronic organic disorders such as dementia. Automatism, on the other hand, is when an individual exhibits exaggerated cooperation with the examiner’s request of continues to perform a movement even after it has been requested. Mannerisms are repetitive, goal-directed movements, while stereotypy refers to unusual, non-goal directed movements. Finally, stuttering is characterized by the repetition of prolongation of sounds during speech. These motor symptoms are commonly seen in various neurological disorders.

The recommended treatment for emotionally unstable personality disorder (borderline type) does not involve a single psychological therapy of drug treatment as a first line of defense. However, for women who prioritize reducing self-harm, DBT is recommended. Drug treatments may be considered for comorbid conditions. According to NICE guidelines on Borderline personality disorder (BPD) (CG78), a comprehensive dialectical behaviour therapy programme should be considered for women with borderline personality disorder who prioritize reducing recurrent self-harm. Brief psychological interventions of less than 3 months’ duration should not be used specifically for borderline personality disorder of for the individual symptoms of the disorder. Drug treatment should not be used specifically for borderline personality disorder of for the individual symptoms of behavior associated with the disorder, such as repeated self-harm, marked emotional instability, risk-taking behavior, and transient psychotic symptoms. If sedatives are used for crisis intervention in a patient with EUPD, they should be prescribed for a maximum period of one week.

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.

The BMI of a person is determined by dividing their weight in kilograms by the square of their height in meters, expressed as kg/m2.

Due to its low therapeutic index, lithium necessitates monitoring.

Narrow Therapeutic Index Drugs

Narrow therapeutic index (NTI) drugs are medications that have a small difference between the amount that causes a therapeutic effect and the amount that causes toxicity. In other words, the therapeutic index (TI) of these drugs is narrow. The TI is a ratio that compares the blood concentration at which a drug causes a therapeutic effect to the amount that causes death of toxicity.

In clinical practice, the TI is the range of doses at which a medication appeared to be effective in clinical trials for a median of participants without unacceptable adverse effects. For most drugs, this range is wide enough, and the maximum plasma concentration of the drug achieved when the recommended doses of a drug are prescribed lie sufficiently above the minimum therapeutic concentration and sufficiently below the toxic concentration.

However, some drugs have a narrow therapeutic index, which means that even small changes in dose of blood concentration can lead to serious adverse effects. The US Food and Drug Administration (FDA) defines a drug product as having an NTI when there is less than a twofold difference in the minimum toxic concentrations and minimum effective concentrations in the blood and safe and effective use of the drug requires careful titration and patient monitoring.

Examples of drugs with a narrow therapeutic index include carbamazepine, lithium, phenytoin, warfarin, digoxin, and gentamicin. These drugs require close monitoring to ensure that the blood concentration remains within the therapeutic range and does not reach toxic levels.

The Simpson-Angus scale was created to evaluate parkinsonism caused by medication, utilizing consistent assessments for stiffness, shaking, and excessive saliva production. The scale solely relies on observable symptoms.

In psychiatry, various questionnaires and interviews are used to assess different conditions and areas. It is important for candidates to know whether certain assessment tools are self-rated of require clinical assistance. The table provided by the college lists some of the commonly used assessment tools and indicates whether they are self-rated of clinician-rated. For example, the HAMD and MADRS are clinician-rated scales used to assess the severity of depression, while the GDS is a self-rated scale used to screen for depression in the elderly. The YMRS is a clinician-rated scale used to assess the severity of mania in patients with bipolar disorder, while the Y-BOCS is used to measure both the severity of OCD and the response to treatment. The GAF provides a single measure of global functioning, while the CGI requires the clinician to rate the severity of the patient’s illness at the time of assessment. The CAMDEX is a tool developed to assist in the early diagnosis and measurement of dementia in the elderly.

Expressed emotion (EE) in schizophrenia was first introduced by Brown et al., which refers to the emotions exhibited by family members towards their loved one with the illness. The James-Lange theory is one of two fundamental theories of emotions, alongside the Cannon-Bard theory. Fromm-Reichmann coined the term ‘schizophrenogenic mother.’ Harris proposed a model of emotional development consisting of five stages. Plutchik identified eight primary emotions.

Locked-in Syndrome: A Condition of Total Dependence on Caregivers

Locked-in syndrome is a medical condition that renders a patient mute, quadriplegic, bedridden, and completely reliant on their caregivers. Despite their physical limitations, patients with locked-in syndrome remain alert and cognitively intact, and can communicate by moving their eyes. This condition typically occurs as a result of an infarction of the pons or medulla, which is often caused by an embolus blocking a branch of the basilar artery.

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.

– Catatonia is a psychiatric syndrome characterized by disturbed motor functions, mood, and thought.
– Key behaviors associated with catatonia include stupor, posturing, waxy flexibility, negativism, automatic obedience, mitmachen, mitgehen, ambitendency, psychological pillow, forced grasping, obstruction, echopraxia, aversion, mannerisms, stereotypies, motor perseveration, echolalia, and logorrhoea.
– These behaviors are often tested in exam questions.
– Karl Ludwig Kahlbaum is credited with the original clinical description of catatonia.