Schizophrenia and other psychoses Flashcards
What are the classic characteristics of psychosis?
hallucinations; delusions and disorder of the form of thought with lack of insight
What is hallucination?
a perception which occurs in the absence of an external stimulus
How is a hallucination experienced?
as originating in real space not just in thoughts; same qualities as normal perception and not subject to any conscious manipulation
When are hallucinations significant?
only in the context of other relevant symptoms
What is seen in the brain activity of those experiencing auditory hallucinations?
pattern is very similar to that in normal volunteers geneerating inner speech except supplementary motor area and hippocampus
What is the function of the supplementary motor area in the context of hallucinations?
monitors self geenerated actions
What is the function of the parahippocampal gyrus in the context of hallucinations?
detects mismatch between perceived and expected activity
What is the core problem pathophysiologically in auditory hallucinations?
self-generated inner speech is not recognised as such and so is attributed to external reality
What are the types of auditory hallucination?
second person; third person and though echo
What is though echo?
patient experiences his own thoughts spoken or repeated outloud
What are visual hallucinations often associated with?
altered consciousness or organic impairment
What is passivity phenomenon?
behaviour is experienced as being controlled by an external agency rather than by the individual
What is thought insertion?
“people can put thoughts into my head”
Waht is thought withdrawal?
“people are taking my thoughts away”
What is thought broadcasting?
“everyone knows my thoughts”
What are teh typical themes of delusion in depression?
disease; nihilism; poverty; sin and guilt
what are the typical themes of delusion in schizophrenia?
control; persecution; reference; religion; love
What are teh typical themes of delusion in mania?
grandiosity; persecution; religion
What determines the specific content of a delusion?
cultural norms eg. someone in japan will probbaly not be worried about MI5
What is usually the origin of delusions?
secondary- an attempt to explain anomalous expereinces eg hallucinations, passiviity expereinces
What are self-referential expereinces?
belief that external events are related to oneself
Give examples of self-referential experiences?
TV or radio are transmitting messages for me or newspapers contain hidden codes
What is the differential diagnosis of psychotic symptoms?
schizophrenia; psychoactive substance use; mania; depression; delirium; dementia; other organic cause
What is delusional perception?
a fully formed delusion which arises from a real/ genuine perception
What are the core psychotic symptoms of schizophrenia?
auditory hallucinations; passivity phenomena; delusional perception
What are the characterstics of auditory hallucinationsin SZ?
thought echo; 3rd person; in form of running commentary
What are the negatvie symptoms of SZ?
reduced amount of speech; motivation; interest/pleasure; social interaction; restricted range of afffect
What is seen premorbidly in patients who develop SZ?
subtle motor, cognitive and social deficits in childhood that become greater as time goes on
What are the prodromal ymptoms of SZ?
gradual onset with non-specific- odd ideas and expereinces, eccentrciity, altered affect
What is the most common outcome of SZ?
multiple epsidoes with signficant chronic progressive impairment
How many patients with SZ have only one epsidoe with no-minimal impairment?
20%
What are the bad prognostic indicators in SZ?
poor pre-morbid adjustment; insidious onset; early onset; cognitivie impairment; enlarged ventricles
What are the good prognostic indicators in SZ?
older age of onset; female gender; marked mood disturbance esp. elation; family history
What is the biggest known risk factor for dveloping SZ?
positive family history
What is seen during pregnancy or birth complications of those who go on to develop SZ?
higher rates of perinatal complications= prematurity; prolonged labour; fetal distress; hypoxia; 2nd trimester viral infections or malnutrition
What is seen in the brain with SZ?
enlarged lateral ventricles; reduced frontotempral volume; reduced activation of prefrontal areas on specific tasks
What test do SZ patients tend to do badly in and why?
Stroop test- involves prefrontal areas
What supports the dopamine hypothesis in SZ?
drugs which release dopamine or D2 receptor agonists a psychotic state or make SZ worse
What are the functions of the D2 receptor family ?
inhibit adenyly cyclase; inhibit voltage-activated calcium channels and open K channels
What are the genes implicated in SZ?
neuregulin; dysbindin; DISC-1
What may precipitate onset/relapse of SZ?
stresss
How can you indentify drug-induced psychosis from other causes of psychosis?
if stop drug; psychosis improves within days
What is depressive psychosis typified by?
mood congruent content of psychotic symptoms
What are the features of delirium?
clouding of consciousness- disorentation in time, place and person; fluctuating severity; worse at night; impaired conc. /memory
What are the psychotic symptoms of delirium?
visual hallucinations +/- audtiory; persecutory delusions; psychomotor distubrnace
What do 3rd person auditory hallucinations suggest?
SZ
Give examples of typical antipsychotics?
chlorpromazine; haloperidol
How is antipsychotic action and D2 receptor blockade related?
strong correlation between average dose rewuired and D2 receptor binding activity
What problsm does D2 blockade cause?
EPSE; hypereprolactinaemia
What is the treatment fro acute dystonic reaction?
IV anticholinergics
What problems can 5HT-2 blockade cause and why?
metabolic syndrome; interactions at serotonin receptors my modulate aspects of hte immune response and inflammation
What problems does histamine blockade cause?
sedation and increased appetite
What is clozapine used for?
treatment resistant SZ
What are the problems associated with clozapine?
agranulocytosis; myocarditis
How often should FBCs be done with clozapine?
weekly for first 6 months; fortnightly for next 6 months; every 4 weeks thereafter
What diseases is formal thought disorder seen with?
SZ and mania
What is formal thought disorder?
group of first rank symptoms of delusions of thought interference-thought withdrawal; thought insertion and thought broadcasting
What diseases is passivity phenomenon seen with?
SZ and substance misuse
What diseases are visual hallucinations seen with?
substance misuse and delirium/dementia
