Basic science of psychosis Flashcards
What is Paranoid delusion?
A false fixed fear of being harmed or persecuted by a particular person or group of people.
What are ideas of reference?
An individual experiencing innocuous or coincidental events and believing that they have strong personal relevance.
What is thought insertion?
A delusion in which an individual believes that thoughts are being placed in their head by an outsider
What is thought broadcasting?
The belief that others can hear or are aware of an individuals thoughts.
Is schizophrenia genetic?
Yes- The lifetime risk of monozygotic twins is 45%
What is the appearance of a brain with poor prognosis?
Reduced frontal lobe volume
Reduced frontal lobe grey matter
Enlarged lateral ventricle volume
Grey matter abnormalities in schizophrenia:
Present early in illness and likely pre morbid (Are there before disease)
Loss due to reduced arborisation and not neurone loss
Progressive in initial years of illness
How is white matter investigated?
Diffusion tensor imagine (DTI)
What do high numbers in fractional anisotropy show?
Healthy white matter tracts
What do high numbers in mean diffusivity mean
Less healthy white matter tracts
Distribution of White matter deficits in schizophrenia
Frontotemporal
Periventricular
What effect do drugs that release dopamine (Eg amphetamine) have?
They cause a psychotic state
What class of drug is used to treat symptoms of schizophrenia?
Dopamine receptor antagonists
Subcortical dopamine hyperactivity leads to…
Psychosis
Mesocortical dopamine hypoactivity leads to…
Negative and cognitive symptoms
Which gene alterations are invovled in schizophrenia?
Neuregulin
Dysbindin
DISC-1
Examples of typical antipsychotics?
Chlorpromazine
Haloperidol
Thioridazine
Fluphenazine
Examples of atypical antipsychotics?
Olanzapine
Risperidone
Clozapine
Atypicals compared to typicals?
Less likely to get extra pyramidal side effects
High 5 HT to D2 ratio
Better efficacy against -ve symptoms
Effective in patients unresponsive to typical drugs
What is akathisia?
Restlessness, particularly in the legs
Side effects of 5HT-2 blockade?
Metabolic syndrome
Histamine blockade side effects?
Sedation
Increased appetite
Alpha blocker side effects?
Increased BP and HR.
Side effects of Clozapine?
Agranulocytosis
Cardiac toxicity
