Schizophrenia Flashcards
When is the common onset ?
adolescence
What are the symptoms ?
Positive = hallucinations (mainly auditory )
Negative = affect mood of patient, cognitive impairment, temporal disorientation
How do the symptoms progress?
Start = positive symptoms more prominent
Negative symptoms more prominent with age
What part of the brain have increased activity during auditory hallucinations?
Brocas area in cortex
What do structural brain studies show?
- ventricular enlargement
- decreased volume of temporal lobe (hippocampus)
- increased dendritic pruning
- no gliosis (no increased abundance of glial cells)
How is the organisation of the neurones disrupted in the cortex ?
Decreased no. small neurones in superficial layers
Increased no. large neurones in deeper layers
What is the indirect circumstantial evidence to implicate dopamine in schizophrenia ?
- reserpine is antipsychotic
- Amphetamine causes toxic psychosis in susceptible individuals
- L-DOPA can trigger psychotic episodes
- Chlorpromazine
Explain the action of chlorpromazine
Increases DA turnover
Increased release of dopamine = increase appearance of metabolites = suggests chlorpromazine is DA receptor antagonist
Is there an increase in dopaminergic transmission in schizophrenia ?
- no consistent evidence
- post mortar brain shows increase in D2 r but could be due to drug treatment
What are dopamine receptor antagonists ?
antipsychotics
What are the typical antipsychotic side effects?
weight gain
sedation
postural hypotension
tachycardia urinary retention
movement disorders
What are the movement disorders caused by antipsychotics ?
Chronic = tardive dyskinesia (can be irreversible)
Acute = Parkinson like syndrome
What is Neuregulin ?
Growth factors that interact with a receptor which regulates neuronal differentiation and migration
Look at notes!!!!!
