lecture 28 Flashcards
1
Q
How many people are affected by mental and neurological disorders?
A
- more than 450 million people around the world
2
Q
How does WHO classify the most significant mental and neurological disorders?
A
Four categories:
- mental diseases
- neurological disorders
- learning and developmental disabilities
- substance abuse disorders
- difference between mental and neurological diseases/disorders has come about through historical ideas about how the brain works
3
Q
What is the distinction between mental and neurological?
A
- the classification relates to an antiquated notion that some disorders were organic (the subject of neurology) while others might be purely functional (the subject of psychiatry) – a malfunction in the mental operations of the brain without an organic cause
- while there is no reason to postulate properties or actions of the mind that are not directly associated with the action of the brain, the classification of “mental” illness – disorders that manifest as abnormal operation of the mind – is still used
software vs hardware
but the two are inexorably related
4
Q
What are learning and developmental disabilities?
A
- include functional limitations that manifest in infancy or childhood as a result of disorders of or injuries to the developing nervous system
5
Q
What are the major types of developmental disability?
A
- genetic
- chromosomal (e.g. Down syndrome)
- seg. autosomal syndromes (Prader-willi, Angelman)
- sex linked, single gene (fragile X, Rett)
- autosomal recessibe (Phenylketonuria, Tay Sachs)
- autosomal dominant (neurocutaneous syndromes e.g. neurofibromatosis)
- multifactorial
- genetic and nutritional (neural tube)
- nutritional
- prenatal and childhood (maternal iodine deficiency leads to Developmental iodine deficiency disorder)
- infections
- prenatal or perinatal (toxoplasmosis, rubella, cytomegalovirus, STD e.g. HIV)
- postnatal or childhood (encephalitis, meningitis, cerebral malaria, polio, trachoma, otitis media)
- toxic exposures
- prenatal (alcohol, lead, mercury, antimicrobials, other drugs e.g. thalidomide)
- perinatal complications
- brain injuries associated with premature birth, birth asphyxia (cerebral palsy, cognitive disabilities, seizure disorders)
- injury
- trauatic brain injuries, vehicle crashes, child abuse and neglect, warfare etc (cognitive, motor, speech, vision, hearing, seizure, and behavioural disabilities)
- poverty, economic disadvantage
- mild mental retardation
6
Q
What are mental disorders?
A
- mental disorders are diseases that affect cognition, emotion and behavioural control and substantially interfere both with the ability of children to learn and with the ability of adults to function in their families, at work and in the broader society
- mental disorders tend to begin early in life and often run a chronic recurrent course
7
Q
What is aetiology of mental disorder?
A
- mental disorders have complex aetiologies that involve interactions among multiple genetic and non-genetic risk factors
8
Q
How is gender related to risk of mental disorders?
A
- males have higher rates of attention deficit hyperactivity disorder, autism, and substance use disorders
- females have higher rates of major depressive disorder, most anxiety disorders, and eating disorders
9
Q
What are the most significant mental disorders?
A
- schizophrenia (enlarged ventricles?)
- bipolar affective disorder (manic depression)
- major depressive disorder
- panic disorder
10
Q
Are there organic biases in mental disorders?
A
- development of pharmacological therapies beginning in the early 1950s
- treated the symptoms of schizophrenia, depression, anxiety disorders, and others
- suggests possible underlying pathophysiology
- anti-psychotics
11
Q
What are anxiety disorders?
A
- abnormal experiencing of anxiety can occur in a variety of ways
- commonly classified as follows:
- generalised anxiety disorder (GAD)
- panic attack
- panic disorder
- phobias
- obsessive compulsive disorder
- post-traumatic stress disorder
12
Q
What drugs are effective in treating anxiety disorders?
A
- benzodiazepine
- anzyolytic drugs
- break down anxiety
- ethanol also effective: used almost invariably in social situations where there might be anxiety/desire to reduce social anxiety
- single molecule can change a very complex phenotype
- GABA receptor
- normally gating a chloride channel (depolarises the membrane)
- tells neurons to settle down
- subtly modulating this will alter tone/firing of systems with this particular receptor
- not completely cured/treated but there is something important about the gaba-ergic system and anxiety
13
Q
What is the efficacy of D2 receptor antagonists in the treatment of schizophrenia?
A
- thought disorder - fragmentation of thought
- very complex
- affects those attributes of meaning and significance and the way we interact with the environment
- and yet a single receptor seems to be at the heart or near the heart of this disorder
- many different anti-psychotic medications
- need far less of a drug that has tighter binding for D2 receptor
- spiperone is tightest need less than 1.0 mg/day
- promazine is lowest affinity - need ~1000mg/day
- some people with this disease don’t respond at all to these kinds of drugs
- complex phenomenology, relatively simple pharmacology
14
Q
What are the most significant neurological diseases?
A
- alzheimer’s disease and other dementias
- epilepsy
- parkinson’s disease
- stroke
AD and dementia (and others) biggest risk factor = age
- as society gets older bigger burden of disease
15
Q
What is dementia?
A
- dementia is a deterioration of intellectual function and other cognitive skills that is of sufficient severity to interfere with social or occupational functioning
