The hippocampal formation includes the dentate gyrus, which is located in the medial temporal lobe. The cerebrum, which is the largest part of the brain, is divided into four lobes: frontal, temporal, parietal, and occipital. The frontal lobe is situated at the front of the cerebrum, while the temporal lobes are on the sides, the parietal lobe is on the top, and the occipital lobe is at the back.

Anticipation refers to the tendency for symptoms of a genetic disorder to manifest at an earlier age in successive generations as the disorder is passed down. This phenomenon is frequently observed in trinucleotide repeat disorders like myotonic dystrophy and Huntington’s disease.

Trinucleotide Repeat Disorders: Understanding the Genetic Basis

Trinucleotide repeat disorders are genetic conditions that arise due to the abnormal presence of an expanded sequence of trinucleotide repeats. These disorders are characterized by the phenomenon of anticipation, which refers to the amplification of the number of repeats over successive generations. This leads to an earlier onset and often a more severe form of the disease.

The table below lists the trinucleotide repeat disorders and the specific repeat sequences involved in each condition:

Condition Repeat Sequence Involved
Fragile X Syndrome CGG
Myotonic Dystrophy CTG
Huntington’s Disease CAG
Friedreich’s Ataxia GAA
Spinocerebellar Ataxia CAG

The mutations responsible for trinucleotide repeat disorders are referred to as ‘dynamic’ mutations. This is because the number of repeats can change over time, leading to a range of clinical presentations. Understanding the genetic basis of these disorders is crucial for accurate diagnosis, genetic counseling, and the development of effective treatments.

The therapy being discussed is dialectical behaviour therapy (DBT), which was created by Marsha Linehan, who had a personality disorder diagnosis and multiple hospital admissions. DBT involves mindfulness practice and the development of interpersonal skills through individual and group therapy sessions. All of the therapies mentioned are recognized treatments for personality disorders. Cognitive analytic therapy focuses on past relationships and object relations, while mentalisation-based therapy aims to improve mentalisation capacity through individual and group therapy. Schema-focused therapy builds on CBT to challenge cognitive coping strategies, and transference-focused therapy uses the therapist-client relationship to assess internal representations of past relational experiences.

Norman Sartorius highlights the iatrogenic stigma of mental illness as the main obstacle to a better life for those suffering from mental disorders. NICE guidelines on schizophrenia also acknowledge the stigma associated with the condition, which is often seen as dangerous and best dealt with away from society. However, research has shown that the fear of violence arising from people with schizophrenia is misplaced. Other factors that may contribute to feelings of exclusion and isolation include compulsory treatment under mental health legislation, medication side effects, and less careful use of diagnostic labels.

Amantadine and QTc Prolongation

Amantadine is a medication used to treat Parkinson’s disease and influenza. It has been associated with QTc prolongation, which can increase the risk of Torsades de points. Therefore, caution should be exercised when prescribing amantadine to patients with risk factors for QT prolongation. If a patient is already taking amantadine and develops a prolonged QTc interval, the medication should be discontinued and an alternative treatment considered. It is important to monitor the QTc interval in patients taking amantadine, especially those with risk factors for QT prolongation.

Attachment Theory and Harlow’s Monkeys

Attachment theory, developed by John Bowlby, suggests that children have an innate tendency to form relationships with people around them to increase their chance of survival. This attachment is different from bonding, which concerns the mother’s feelings for her infant. Children typically single out a primary caregiver, referred to as the principle attachment figure, from about 1-3 months. The quality of a person’s early attachments is associated with their adult behavior, with poor attachments leading to withdrawn individuals who struggle to form relationships and good attachments leading to socially competent adults who can form healthy relationships.

Bowlby’s attachment model has four stages: preattachment, attachment in the making, clear-cut attachment, and formation of reciprocal attachment. The time from 6 months to 36 months is known as the critical period, during which a child is most vulnerable to interruptions in its attachment. Attachments are divided into secure and insecure types, with insecure types further divided into avoidant and ambivalent types.

Harlow’s experiment with young rhesus monkeys demonstrated the importance of the need for closeness over food. The experiment involved giving the monkeys a choice between two different mothers, one made of soft terry cloth but provided no food and the other made of wire but provided food from an attached baby bottle. The baby monkeys spent significantly more time with their cloth mother than with their wire mother, showing the importance of attachment and closeness in early development.

The origin of the term dementia praecox is a topic of controversy. While some sources credit Kraepelin with popularizing the term, others argue that it was first used in its Latin form by Arnold Pick in 1891. The original term demence precoce was coined by Morel in 1852. Despite this, the College has chosen to attribute the term to Kraepelin. Therefore, if the question refers to demence precoce, the answer should be Morel, and if it refers to dementia praecox, Kraepelin should be selected.

History of Psychiatric Terms

In the exams, it is important to be familiar with the individuals associated with certain psychiatric terms. For example, Kraepelin is associated with dementia praecox and manic depression, while Bleuler is associated with schizophrenia. Other terms and their associated individuals include Hebephrenia (Hecker), Catatonia (Kahlbaum), Schizoaffective (Kasanin), Neurasthenia (Beard), Unipolar and bipolar (Kleist), Hypnosis (Braid), Group dynamics (Lewin), Group psychotherapy (Moreno), Psychopathic inferiority (Koch), Psychiatry (Reil), and Institutional Neurosis (Barton).

It should be noted that there is some debate over the origins of certain terms. While Kraepelin is often credited with coining the term dementia praecox, some sources suggest that it was first used in its Latin form by Arnold Pick in 1891. The original term demence precoce was first used by Morel in 1852. Despite this, the College appears to favor the Kraepelin attribution.

Cotard’s syndrome is a disorder characterized by sudden onset of nihilistic delusions, including beliefs of poverty, negation, and meaninglessness. Hypochondriacal delusions and feelings of guilt may also be present. This condition is more prevalent in elderly individuals and females, and is often associated with depression and organic illnesses.

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.

It is advisable to avoid agents with longer half lives as they have a tendency to induce drowsiness in patients.

Benzodiazepines are a class of drugs commonly used to treat anxiety and sleep disorders. It is important to have a working knowledge of the more common benzodiazepines and their half-life. Half-life refers to the amount of time it takes for half of the drug to be eliminated from the body.

Some of the more common benzodiazepines and their half-life include diazepam with a half-life of 20-100 hours, clonazepam with a half-life of 18-50 hours, chlordiazepoxide with a half-life of 5-30 hours, nitrazepam with a half-life of 15-38 hours, temazepam with a half-life of 8-22 hours, lorazepam with a half-life of 10-20 hours, alprazolam with a half-life of 10-15 hours, oxazepam with a half-life of 6-10 hours, zopiclone with a half-life of 5-6 hours, zolpidem with a half-life of 2 hours, and zaleplon with a half-life of 2 hours. Understanding the half-life of these drugs is important for determining dosages and timing of administration.

Genetic Conditions and Their Features

Genetic conditions are disorders caused by abnormalities in an individual’s DNA. These conditions can affect various aspects of a person’s health, including physical and intellectual development. Some of the most common genetic conditions and their features are:

– Downs (trisomy 21): Short stature, almond-shaped eyes, low muscle tone, and intellectual disability.
– Angelman syndrome (Happy puppet syndrome): Flapping hand movements, ataxia, severe learning disability, seizures, and sleep problems.
– Prader-Willi: Hyperphagia, excessive weight gain, short stature, and mild learning disability.
– Cri du chat: Characteristic cry, hypotonia, down-turned mouth, and microcephaly.
– Velocardiofacial syndrome (DiGeorge syndrome): Cleft palate, cardiac problems, and learning disabilities.
– Edwards syndrome (trisomy 18): Severe intellectual disability, kidney malformations, and physical abnormalities.
– Lesch-Nyhan syndrome: Self-mutilation, dystonia, and writhing movements.
– Smith-Magenis syndrome: Pronounced self-injurious behavior, self-hugging, and a hoarse voice.
– Fragile X: Elongated face, large ears, hand flapping, and shyness.
– Wolf Hirschhorn syndrome: Mild to severe intellectual disability, seizures, and physical abnormalities.
– Patau syndrome (trisomy 13): Severe intellectual disability, congenital heart malformations, and physical abnormalities.
– Rett syndrome: Regression and loss of skills, hand-wringing movements, and profound learning disability.
– Tuberous sclerosis: Hamartomatous tumors, epilepsy, and behavioral issues.
– Williams syndrome: Elfin-like features, social disinhibition, and advanced verbal skills.
– Rubinstein-Taybi syndrome: Short stature, friendly disposition, and moderate learning disability.
– Klinefelter syndrome: Extra X chromosome, low testosterone, and speech and language issues.
– Jakob’s syndrome: Extra Y chromosome, tall stature, and lower mean intelligence.
– Coffin-Lowry syndrome: Short stature, slanting eyes, and severe learning difficulty.
– Turner syndrome: Short stature, webbed neck, and absent periods.
– Niemann Pick disease (types A and B): Abdominal swelling, cherry red spot, and feeding difficulties.

It is important to note that these features may vary widely among individuals with the same genetic condition. Early diagnosis and intervention can help individuals with genetic conditions reach their full potential and improve their quality of life.

The serum concentration of valproic acid may be elevated by chlorpromazine, although the reason for this is not fully understood. However, this outcome is widely acknowledged.

Chlorpromazine: Photosensitivity Reactions and Patient Precautions

Chlorpromazine, the first drug used for psychosis, is a common topic in exams. However, it is important to note that photosensitivity reactions are a known side effect of its use. Patients taking chlorpromazine should be informed of this and advised to take necessary precautions. Proper education and awareness can help prevent potential harm from photosensitivity reactions.

Rapid Risk Assessment for Sex Offence Recidivism (RRASOR)

The Rapid Risk Assessment for Sex Offence Recidivism (RRASOR) is a well-known actuarial tool that is used to predict the likelihood of sex offence recidivism. It comprises of four items that have been proven to have predictive accuracy for sex offence recidivism. These items include the number of past sex offence convictions of charges, the age of the offender being less than 25, the offender being unrelated to the victim, and the gender of the victim.

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.

Depression, suicidality, and aggression have been linked to low levels of 5-HIAA in the CSF.

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.

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.

The SASQ is a screening questionnaire that consists of a single question asking about the last time an individual had more than a certain number of alcoholic drinks in one day (8 for men and 6 for women). If the response indicates that this occurred within the past 3 months, it suggests that the individual may be engaging in harmful of hazardous drinking.

Alcohol screening tools are available to assist in the diagnosis of alcohol problems. One such tool is the AUDIT (Alcohol Use Disorders Identification Test), which consists of 10 questions and covers harmful use, hazardous use, and dependence. Another tool is the FAST (Fast Alcohol Screening Test), which has just 4 questions and was developed for use in a busy medical setting. The CAGE is a well-known 4 question screening tool, but recent research has questioned its value. Other tools include SASQ (Single alcohol screening questionnaire), PAT (Paddington Alcohol Test), MAST (Michigan Alcoholism Screening Test), and RAPS4 (Rapid Alcohol Problem Screen 4). These tools can help identify hazardous of harmful alcohol consumption and alcohol dependence.

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.

Understanding Turner Syndrome

Turner syndrome is a genetic disorder that affects only females. It occurs when one of the two X chromosomes is missing of partially missing. This happens randomly and does not increase the risk of the condition in future siblings. Although X-inactivation occurs in females, having only one X chromosome can cause issues as not all genes are inactivated in the inactivated X chromosome.

The features of Turner syndrome include short stature, a webbed neck, a broad chest with widely spaced nipples, gonadal dysfunction leading to amenorrhea and infertility, congenital heart disease, and hypothyroidism. Despite these physical characteristics, girls with Turner syndrome typically have normal intelligence, with a mean full-scale IQ of 90. However, they may struggle with nonverbal, social, and psychomotor skills. It is important to understand the symptoms and effects of Turner syndrome to provide appropriate care and support for affected individuals.

Depression screening can be done using two questions that ask about feeling down, depressed, of hopeless and having little interest of pleasure in doing things. A ‘yes’ answer to either question prompts a more in-depth assessment using tools such as the Hospital Anxiety and Depression (HAD) scale of the Patient Health Questionnaire (PHQ-9). The HAD scale consists of 14 questions, while the PHQ-9 asks about 9 problems over the last 2 weeks. NICE grades depression into ‘less severe’ and ‘more severe’ based on a PHQ-9 score of <16 and >16, respectively. The severity of depression can range from subthreshold and mild to moderate and severe. It is important to assess depression severity to determine appropriate treatment options.

Schizophrenia Risk According to Gottesman

Irving I. Gottesman conducted family and twin studies in European populations between 1920 and 1987 to determine the risk of developing schizophrenia for relatives of those with the disorder. The following table displays Gottesman’s findings, which show the average lifetime risk for each relationship:

General population: 1%
First cousin: 2%
Uncle/aunt: 2%
Nephew/niece: 4%
Grandchildren: 5%
Parents: 6%
Half sibling: 6%
Full sibling: 9%
Children: 13%
Fraternal twins: 17%
Offspring of dual matings (both parents had schizophrenia): 46%
Identical twins: 48%

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.

The Cerebellum: Anatomy and Function

The cerebellum is a part of the brain that consists of two hemispheres and a median vermis. It is separated from the cerebral hemispheres by the tentorium cerebelli and connected to the brain stem by the cerebellar peduncles. Anatomically, it is divided into three lobes: the flocculonodular lobe, anterior lobe, and posterior lobe. Functionally, it is divided into three regions: the vestibulocerebellum, spinocerebellum, and cerebrocerebellum.

The vestibulocerebellum, located in the flocculonodular lobe, is responsible for balance and spatial orientation. The spinocerebellum, located in the medial section of the anterior and posterior lobes, is involved in fine-tuned body movements. The cerebrocerebellum, located in the lateral section of the anterior and posterior lobes, is involved in planning movement and the conscious assessment of movement.

Overall, the cerebellum plays a crucial role in motor coordination and control. Its different regions and lobes work together to ensure smooth and precise movements of the body.

The term ‘extinction’ has different meanings in classical and operant conditioning. In classical conditioning, it refers to a decrease in a conditioned response when a conditioned stimulus is repeatedly presented without the unconditioned stimulus. In operant conditioning, it refers to the decrease in an operant response when it is no longer reinforced. The options of negative reinforcement, negative punishment, and positive punishment are not relevant to classical conditioning.

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.

The Case of Phineas Gage and the Importance of the Frontal Lobe

Phineas Gage was a railroad worker who experienced a traumatic accident where an iron pole went through his frontal lobe. Despite surviving the incident, his personality underwent a significant change. This case was crucial in advancing our knowledge of the frontal lobe’s function.

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.

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.

Genome-wide association studies (GWAS) have demonstrated that individuals carrying specific variant alleles in the promoter region of the 5-HT2C receptor gene are less susceptible to significant weight gain when undergoing antipsychotic treatment.

Olanzapine belongs to the thienobenzodiazepine class.

Antipsychotics can be classified in different ways, with the most common being typical (first generation) and atypical (second generation) types. Typical antipsychotics block dopamine (D2) receptors and have varying degrees of M1, Alpha-1, and H1 receptor blockade. Atypical antipsychotics have a lower propensity for extrapyramidal side-effects and are attributed to the combination of relatively lower D2 antagonism with 5HT2A antagonism. They are also classified by structure, with examples including phenothiazines, butyrophenones, thioxanthenes, diphenylbutylpiperidine, dibenzodiazepines, benzoxazoles, thienobenzodiazepine, substituted benzamides, and arylpiperidylindole (quinolone). Studies have found little evidence to support the superiority of atypicals over typicals in terms of efficacy, discontinuation rates, of adherence, with the main difference being the side-effect profile. The Royal College also favors classification by structure.

Kurt Schneider identified five characteristics of formal thought disorders, which include substitution, omission, fusion, drivelling, and derailment. Omission refers to the tendency for individuals to leave out certain thoughts of parts of their thoughts during conversations, without realizing it. On the other hand, Cameron described additional features of formal thought disorders, such as asyndesis, interpenetration, metonymy, and overinclusion. For more information on this topic, interested readers may refer to the Textbook of Psychiatry, 3rd edition, by Puri BK and Treasaden IH.

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.

Genetics plays a role in the development of Alzheimer’s disease, with different genes being associated with early onset and late onset cases. Early onset Alzheimer’s, which is rare, is linked to three genes: amyloid precursor protein (APP), presenilin one (PSEN-1), and presenilin two (PSEN-2). The APP gene, located on chromosome 21, produces a protein that is a precursor to amyloid. The presenilins are enzymes that cleave APP to produce amyloid beta fragments, and alterations in the ratios of these fragments can lead to plaque formation. Late onset Alzheimer’s is associated with the apolipoprotein E (APOE) gene on chromosome 19, with the E4 variant increasing the risk of developing the disease. People with Down’s syndrome are also at high risk of developing Alzheimer’s due to inheriting an extra copy of the APP gene.

Boys typically begin puberty around the age of 12, while girls typically begin around the age of 11.

Puberty

Puberty is a natural process that occurs in both boys and girls. The age range for the onset of puberty is between 8-14 years for females and 9-14 years for males, with the mean age of onset being 11 years for girls and 12 years for boys. The duration of puberty is typically 3-4 years. The onset of puberty is marked by the appearance of secondary sex characteristics, such as breast development in females and testicular enlargement in males. These characteristics evolve over time and are rated into 5 stages according to Tanner’s criteria. The sequence of events differs between boys and girls, with the onset of breast development (thelarche) generally preceding the onset of the first period (menarche) by around 2 years in girls. The pubertal growth spurt occurs during stages 3 to 4 in most boys and during stages 2 and 3 in girls. Precocious puberty, which occurs earlier than usual, is more common in girls than in boys. The age of onset of puberty in girls has been decreasing over time, with environmental factors such as nutrition potentially playing a role in this trend.

Reboxetine is classified as a selective inhibitor of noradrenaline reuptake (NRI), which means it works by preventing the reuptake of noradrenaline and increasing its levels in the body. This medication is typically prescribed as a secondary option for treating acute depressive episodes of major depression when SSRIs are ineffective of not well-tolerated.

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).

Antipsychotic drugs are known to cause weight gain, but some more than others. The reason for this is not due to a direct metabolic effect, but rather an increase in appetite and a decrease in activity levels. The risk of weight gain appears to be linked to clinical response. There are several suggested mechanisms for this, including antagonism of certain receptors and hormones that stimulate appetite. The risk of weight gain varies among different antipsychotics, with clozapine and olanzapine having the highest risk. Management strategies for antipsychotic-induced weight gain include calorie restriction, low glycemic index diet, exercise, and switching to an alternative antipsychotic. Aripiprazole, ziprasidone, and lurasidone are recommended as alternative options. Other options include aripiprazole augmentation, metformin, orlistat, liraglutide, and topiramate.

Kleine-Levin Syndrome: A Mysterious Condition

Kleine-Levin syndrome is a peculiar disorder that typically affects adolescent boys. It is characterized by an excessive need for sleep and an insatiable appetite when awake. The condition is also associated with emotional and behavioral issues such as irritability and aggression.

The onset of symptoms is sudden and can last for several days to weeks before disappearing. This is followed by a period of normalcy, only to be followed by another episode. This pattern can continue for years, but the severity of symptoms tends to decrease over time. During the periods between episodes, those affected appear to be perfectly healthy with no signs of physical of behavioral dysfunction. The media has dubbed this condition as Sleeping Beauty syndrome.

Despite extensive research, the cause of Kleine-Levin syndrome remains unknown. However, the prognosis is generally positive, with most individuals making a full recovery.

The half-life of a drug is the time taken for its concentration to fall to one half of its value. Drugs with long half-lives may require a loading dose to achieve therapeutic plasma concentrations rapidly. It takes about 4.5 half-lives to reach steady state plasma levels. Most drugs follow first order kinetics, where a constant fraction of the drug in the body is eliminated per unit time. However, some drugs may follow zero order kinetics, where the plasma concentration of the drug decreases at a constant rate, despite the concentration of the drug. For drugs with nonlinear kinetics of dose-dependent kinetics, the relationship between the AUC of CSS and dose is not linear, and the kinetic parameters may vary depending on the administered dose.

– 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.

Heuristics: Cognitive Shortcuts that can Lead to Diagnostic Errors

In the 1970s, Tversky and Kahneman proposed that humans use cognitive heuristics, of mental shortcuts, to simplify complex decision-making processes. However, these heuristics can also lead to systematic errors. One such heuristic is the representativeness bias, where individuals judge the likelihood of an event based on how closely it resembles a stereotype. For example, a person described as shy and detail-oriented may be more likely to be perceived as a librarian than a farmer.

Another heuristic is the availability bias, where individuals favor recent and readily available information over more accurate but less accessible information. This can lead to overestimating the frequency of certain events, such as violent crime. The anchoring-and-adjustment bias occurs when individuals lock onto salient features in a patient’s initial presentation and fail to adjust their impression in light of new information.

The framing effect is another bias where individuals react differently to a choice depending on how the information is presented. For example, a pharmaceutical company may present a drug as having a 95% cure rate, making it seem superior to a drug with a 2.5% failure rate. Base rate neglect occurs when individuals ignore underlying incident rates of population-based knowledge, leading to unnecessary testing of treatment.

Confirmation bias is a tendency to interpret information to fit preconceived diagnoses, rather than considering alternative explanations. The conjunction rule is the incorrect belief that the probability of multiple events being true is greater than a single event. Finally, diagnostic momentum occurs when clinicians continue a course of action initiated by previous clinicians without considering new information.

Overall, while heuristics can be useful in simplifying complex decision-making processes, they can also lead to diagnostic errors if not used appropriately. It is important for clinicians to be aware of these biases and actively work to avoid them in their practice.

Understanding the Placebo Effect

In general, a placebo is an inert substance that has no pharmacological activity but looks, smells, and tastes like the active drug it is compared to. The placebo effect is the observable improvement seen when a patient takes a placebo, which results from patient-related factors such as expectations rather than the placebo itself. Negative effects due to patient-related factors are termed the nocebo effect.

Active placebos are treatments with chemical activity that mimic the side effects of the drug being tested in a clinical trial. They are used to prevent unblinding of the drug versus the placebo control group. Placebos need not always be pharmacological and can be procedural, such as sham electroconvulsive therapy.

The placebo effect is influenced by factors such as the perceived strength of the treatment, the status of the treating professional, and the branding of the compound. The placebo response is greater in mild illness, and the response rate is increasing over time. Placebo response is usually short-lived, and repeated use can lead to a diminished effect, known as placebo sag.

It is difficult to separate placebo effects from spontaneous remission, and patients who enter clinical trials generally do so when acutely unwell, making it challenging to show treatment effects. Breaking the blind may influence the outcome, and the expectancy effect may explain why active placebos are more effective than inert placebos. Overall, understanding the placebo effect is crucial in clinical trials and personalized medicine.

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.

Pharmacokinetics in Pregnancy

During pregnancy, there are significant changes in maternal physiology that can affect the pharmacokinetics of drugs. These changes are most pronounced in the third trimester. One of the most notable changes is an increase in plasma volume, which can lead to haemodilution and a decrease in the concentration of plasma albumin. As a result, the total plasma concentrations of albumin-bound drugs may decrease during pregnancy. Additionally, lipophilic drugs may have an increased volume of distribution due to the increase in plasma volume.

Progesterone levels are also elevated during pregnancy, which can lead to delayed gastric emptying and reduced small intestine motility. This may affect the absorption of drugs, but the overall impact on bioavailability is likely to be relatively small.

The activity of hepatic drug-metabolizing enzymes can also change during pregnancy. Estrogens and progesterone can induce some CYP enzymes and inhibit others, leading to altered drug metabolism.

Finally, renal blood flow and the glomerular filtration rate increase during pregnancy, which can enhance the elimination of some drugs. The GFR can increase by up to 50% during pregnancy. These changes in pharmacokinetics during pregnancy must be taken into account when prescribing drugs to pregnant women.

Alternative Routes of Administration for Antidepressants

While most antidepressants are taken orally, there are a few alternative routes of administration available. However, it is important to note that these non-oral preparations should only be used when absolutely necessary, as they may not have a UK licence.

One effective alternative route is sublingual administration of fluoxetine liquid. Buccal administration of selegiline is also available. Crushed amitriptyline has been shown to be effective when administered via this route.

Intravenous administration is another option, with several antidepressants available in IV preparations, including citalopram, escitalopram, mirtazapine, amitriptyline, clomipramine, and allopregnanolone (which is licensed in the US for postpartum depression). Ketamine has also been shown to be effective when administered intravenously.

Intramuscular administration of flupentixol has been shown to have a mood elevating effect, but amitriptyline was discontinued as an IM preparation due to the high volumes required.

Transdermal administration of selegiline is available, and suppositories containing amitriptyline, clomipramine, imipramine, and trazodone have been manufactured by pharmacies, although there is no clear data on their effectiveness. Sertraline tablets and doxepin capsules have also been given rectally.

Suboxone vs. Subutex: What’s the Difference?

Suboxone and Subutex are both medications used to treat opioid addiction. However, there are some key differences between the two.

Suboxone is a combination of buprenorphine and naloxone. The naloxone is added to prevent people from injecting the medication, as this was a common problem with pure buprenorphine tablets. If someone tries to inject Suboxone, the naloxone will cause intense withdrawal symptoms. However, if the tablet is swallowed as directed, the naloxone is not absorbed by the gut and does not cause any problems.

Subutex, on the other hand, contains only buprenorphine and does not include naloxone. This means that it may be more likely to be abused by injection, as there is no deterrent to prevent people from doing so.

Overall, both Suboxone and Subutex can be effective treatments for opioid addiction, but Suboxone may be a safer choice due to the addition of naloxone.

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 patient’s long-term use of a first-generation depot antipsychotic and the involuntary symptoms presented suggest a diagnosis of tardive dyskinesia. Acute anxiety is unlikely as the patient has a long standing relationship with their psychiatrist and the symptom combination does not fit. Akathisia, characterized by restlessness and leg movement, is also an unlikely diagnosis. Neuroleptic malignant syndrome (NMS) can be ruled out as the patient has had symptoms for two years. The patient is compliant with medication, has no psychotic symptoms, and is well-functioning in their job and home life, making a relapse of schizophrenia an incorrect diagnosis.

Memory Forms

Memory is the ability to store, retain, and retrieve information. There are different forms of memory, including sensory memory, short-term/working memory, and long-term memory.

Sensory memory is the capacity for briefly retaining the large amounts of information that people encounter daily. It includes echoic memory (gathered through auditory stimuli), iconic memory (gathered through sight), and haptic memory (acquired through touch).

Short-term memory is the ability to keep a small amount of information available for a short period of time. Atkinson and Shiffrin’s multistore model (1968) suggests the existence of a short-term storehouse with limited capacity. Baddeley and Hitch (1974) further developed the concept of short-term memory, which eventually became known as Baddeley’s multi-storehouse model (2000). This model includes the central executive, visuospatial sketchpad, phonological buffer/loop, and episodic buffer.

Long-term memory includes declarative (of explicit) memories, which can be consciously retrieved, and nondeclarative (of implicit) memories, which cannot. Declarative memory includes episodic memory (stores personal experiences) and semantic memory (stores information about facts and concepts). Non-declarative memory includes procedural memory (recalls motor and executive skills), associative memory (storage and retrieval of information through association with other information), and non-associative memory (refers to newly learned behavior through repeated exposure to an isolated stimulus).

Overall, memory is a complex and essential cognitive function that plays a crucial role in learning, reasoning, and understanding.

The half-life of a drug is the time taken for its concentration to fall to one half of its value. Drugs with long half-lives may require a loading dose to achieve therapeutic plasma concentrations rapidly. It takes about 4.5 half-lives to reach steady state plasma levels. Most drugs follow first order kinetics, where a constant fraction of the drug in the body is eliminated per unit time. However, some drugs may follow zero order kinetics, where the plasma concentration of the drug decreases at a constant rate, despite the concentration of the drug. For drugs with nonlinear kinetics of dose-dependent kinetics, the relationship between the AUC of CSS and dose is not linear, and the kinetic parameters may vary depending on the administered dose.

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.

Antipsychotics were initially classified as typical of atypical based on their propensity for EPS, with only clozapine and quetiapine being considered fully atypical due to their low risk of EPS. However, a more recent classification system categorizes antipsychotics as first- of second-generation (FGAs/SGAs) based on their introduction date.

Kohlberg’s Six Stages of Moral Development

Kohlberg’s theory of moral development consists of six stages that can be categorized into three levels. The first level is the preconventional stage, which is characterized by obedience and punishment orientation, where the focus is on the direct consequences of actions and unquestioning deference to power. The second stage is the self-interest orientation, where right behavior is defined purely by what is in the individual’s own interest.

The second level is the conventional stage, which is characterized by interpersonal accord and conformity, where the focus is on how the individual will appear to others. The behavior should accord with a consensus view on what is good. The second stage is the authority and social order obedience driven, where what is lawful is judged to be morally right. Right behavior is dictated by societal rules, and there is a greater respect for social order and the need for laws.

The third level is the postconventional stage, which is characterized by the social contract orientation, where individual rights determine behavior. The individual views laws and rules as flexible tools for improving human purposes. The fourth stage is the universal ethical principles orientation, where the right action is the one that is consistent with abstract reasoning using universal ethical principles.

It is important to note that the age ranges for Kohlberg’s developmental stages are rough guides, and sources vary widely. Kohlberg developed his stage theory following an experiment he conducted on 72 boys aged 10-16. However, the theory is criticized as sexist as it only included boys.

Understanding Social Loafing

Social loafing is a common phenomenon that occurs when people work in groups. It refers to the tendency of individuals to exert less effort when working in a group than when working alone. This can be attributed to the diffusion of responsibility, where individuals feel less accountable for their actions when working in a group. As a result, they may not put in as much effort as they would if they were working alone. Social loafing can have negative consequences for group performance, as it can lead to a lack of motivation and a decrease in productivity. Therefore, it is important to understand the causes of social loafing and take steps to prevent it from occurring in group settings.

The foramen lacerum is a opening located in the middle cranial fossa at the base of the skull.

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.

While the majority of SSRIs are believed to have minimal impact on the QTc interval, studies have demonstrated that citalopram and escitalopram can lead to QTc prolongation.

Antidepressants and Their Cardiac Effects

SSRIs are generally recommended for patients with cardiac disease as they may protect against myocardial infarction (MI). Untreated depression worsens prognosis in cardiovascular disease. Post MI, SSRIs and mirtazapine have either a neutral of beneficial effect on mortality. Sertraline is recommended post MI, but other SSRIs and mirtazapine are also likely to be safe. However, citalopram is associated with Torsades de pointes (mainly in overdose). Bupropion, citalopram, escitalopram, moclobemide, lofepramine, and venlafaxine should be used with caution of avoided in those at risk of serious arrhythmia (those with heart failure, left ventricular hypertrophy, previous arrhythmia, of MI).

Tricyclic antidepressants (TCAs) have established arrhythmogenic activity which arises as a result of potent blockade of cardiac sodium channels and variable activity at potassium channels. ECG changes produced include PR, QRS, and QT prolongation and the Brugada syndrome. Lofepramine is less cardiotoxic than other TCAs and seems to lack the overdose arrhythmogenicity of other TCAs. QT changes are not usually seen at normal clinical doses of antidepressants (but can occur, particularly with citalopram/escitalopram). The arrhythmogenic potential of TCAs and other antidepressants is dose-related.

Overall, SSRIs are recommended for patients with cardiac disease, while caution should be exercised when prescribing TCAs and other antidepressants, especially in those at risk of serious arrhythmia. It is important to monitor patients closely for any cardiac effects when prescribing antidepressants.

Attitude scales are used to measure a person’s feelings and thoughts towards something. There are several types of attitude scales, including the Thurstone scale, Likert scale, semantic differential scale, and Gutman scale. The Thurstone scale involves creating a list of statements and having judges score them based on their negativity of positivity towards an issue. Respondents then indicate whether they agree of disagree with each statement. The Likert scale asks respondents to indicate their degree of agreement of disagreement with a series of statements using a five-point scale. The semantic differential scale presents pairs of opposite adjectives and asks respondents to rate their position on a five- of seven-point scale. The Gutman scale involves a list of statements that can be ordered hierarchically, with each statement having a corresponding weight. Respondents’ scores on the scale indicate the number of statements they agree with.

Pareidolic illusions are vivid illusions that can occur from indistinct stimuli, such as seeing a face in the clouds. These illusions are a result of fantasy and vivid visual imagery and can intensify with concentration. Affect illusions arise from a particular mood state and disappear with concentration. Autoscopic hallucinations involve seeing oneself, such as in an out-of-body experience. Charles Bonnet syndrome is a type of hallucination that occurs in elderly people with reduced visual acuity. Complete illusions occur in the context of inattention, where an incomplete stimulus is perceived as complete. For more information, refer to Casey PR and Kelly B’s book, Fish’s Clinical Psychopathology: Signs and Symptoms in Psychiatry.

Hepatic Impairment: Recommended Drugs

Patients with hepatic impairment may experience reduced ability to metabolize drugs, toxicity, enhanced dose-related side effects, reduced ability to synthesize plasma proteins, and elevated levels of drugs subject to first-pass metabolism due to reduced hepatic blood flow. The Maudsley Guidelines 14th Ed recommends the following drugs for patients with hepatic impairment:

Antipsychotics: Paliperidone (if depot required), Amisulpride, Sulpiride

Antidepressants: Sertraline, Citalopram, Paroxetine, Vortioxetine (avoid TCA and MAOI)

Mood stabilizers: Lithium

Sedatives: Lorazepam, Oxazepam, Temazepam, Zopiclone 3.75mg (with care)

The initial version of ICD-10 was released in 1992, while the first edition of ICD was published in 1855 to standardize the classification of causes of death. In 1948, ICD underwent a major revision and expanded from solely recording causes of death to encompass the International Lists of Diseases and Causes of Death, which was the 6th edition. DSM 4 was published in 1994, and there were no noteworthy alterations to the ICD/ DSM classifications in 1998.

Phenomena of Memory

There are several phenomena related to memory that people may experience. Jamais vu is when someone cognitively knows they have experienced a situation, but it does not feel familiar to them. Confabulation is when someone falsifies a memory while in clear consciousness. Déjà vu is a feeling of familiarity for a new event that has not been experienced before. Derealisation is a feeling of unreality in perception and altered feelings towards perceived objects. Finally, panoramic recall is when a patient feels like they are rapidly re-enacting long periods of their life.

The inhibition of sexual behavior is caused by the activation of 5-HT2 receptors. However, this effect can be reversed by using 5-HT2 antagonists like cyproheptadine and 5-HT1a agonists like buspirone. These drugs are effective in treating sexual dysfunction caused by selective serotonin reuptake inhibitors (SSRIs).

Antidepressants can cause sexual dysfunction as a side-effect, although the rates vary. The impact on sexual desire, arousal, and orgasm can differ depending on the type of antidepressant. It is important to rule out other causes and consider non-pharmacological strategies such as reducing the dosage of taking drug holidays. If necessary, switching to a lower risk antidepressant of using pharmacological options such as phosphodiesterase inhibitors of mirtazapine augmentation can be considered. The Maudsley Guidelines 14th Edition provides a helpful table outlining the risk of sexual dysfunction for different antidepressants.

Argyll Robertson Pupil: Accommodation Retained

The Argyll Robertson pupil is a notable topic in medical exams, as it is associated with tertiary syphilis, which is a crucial differential diagnosis for various psychiatric conditions like mood disorders, dementia, and psychosis. This type of pupil reacts poorly to light but normally to near stimuli, such as accommodation and convergence. They are typically small and irregular in shape, but they do not usually affect visual acuity. Mydriatic agents are not effective in dilating the Argyll Robertson pupil. Although this type of pupil is often considered pathognomonic of tertiary syphilis, it has also been observed in diabetes.

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.

Freud’s Structural Theory: Understanding the Three Areas of the Mind

According to Freud’s structural model, the human mind is divided into three distinct areas: the Id, the Ego, and the Superego. The Id is the part of the mind that contains instinctive drives and operates on the ‘pleasure principle’. It functions without a sense of time and is governed by ‘primary process thinking’. The Ego, on the other hand, attempts to modify the drives from the Id with external reality. It operates on the ‘reality principle’ and has conscious, preconscious, and unconscious aspects. It is also home to the defense mechanisms. Finally, the Superego acts as a critical agency, constantly observing a person’s behavior. Freud believed that it developed from the internalized values of a child’s main caregivers. The Superego contains the ‘ego ideal’, which represents ideal attitudes and behavior. It is often referred to as the conscience. Understanding these three areas of the mind is crucial to understanding Freud’s structural theory.

Prescribing medication for elderly individuals requires consideration of their unique pharmacokinetics and pharmacodynamics. As the body ages, changes in distribution, metabolism, and excretion can affect how medication is absorbed and processed. For example, reduced gastric acid secretion and motility can impact drug absorption, while a relative reduction of body water to body fat can alter the distribution of lipid soluble drugs. Additionally, hepatic metabolism of drugs decreases with age, and the kidneys become less effective, leading to potential accumulation of certain drugs.

In terms of pharmacodynamics, receptor sensitivity tends to increase during old age, meaning smaller doses may be needed. However, older individuals may also take longer to respond to treatment and have an increased incidence of side-effects. It is important to start with a lower dose and monitor closely when prescribing medication for elderly patients, especially considering the potential for interactions with other medications they may be taking.

Erik Erikson and Daniel Levinson expanded the understanding of adult development. Erikson proposed a life-span model of human development consisting of eight successive psychosocial stages, each associated with an inherent conflict of crisis that the individual must encounter and successfully resolve to proceed with development. Levinson proposed a developmental theory consisting of universal stages of phases that extend from the infancy state to the elderly state, based on biographical interviews of 40 men in America. Both theorists maintained that personality develops in a predetermined order and builds upon each previous stage, and that failure to successfully negotiate a stage can result in a reduced ability to complete further stages and therefore a more unhealthy personality and sense of self. However, Levinson’s theory is age-based rather than event-based, and his model proposed a ‘life sequence’ consisting of a series of alternating stable (structure-building) periods and cross-era transitional (structure-changing) periods, with transitional periods typically lasting 5 years.

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.

Water intoxication can cause polyuria and dilutional hyponatremia, but it does not typically lead to renal impairment. It is important to differentiate this condition from nephrogenic diabetes insipidus, which can develop in a significant percentage of patients on long-term lithium therapy and may present with nocturia as an early sign. While elevated calcium levels may occur in some patients on lithium, hyperparathyroidism is not a common clinical symptom. Tubulointerstitial nephritis is a rare complication of lithium therapy. The syndrome of inappropriate ADH secretion is not typically associated with polyuria of renal impairment and is not commonly linked to lithium therapy.

To avoid potential liver damage, it is recommended to conduct liver function tests (LFTs) before starting agomelatine and periodically at 3, 6, 12, and 24 weeks after beginning treatment. If serum transaminases levels exceed three times the upper normal limit of if symptoms of liver disorder arise, agomelatine treatment should be discontinued.

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.