Schizophrenia Flashcards
Symptoms
Positive symptoms (added to someone’s behaviour)
- Delusions
- Hallucinations
- Odd behaviour
Negative symptoms (losing a normal behaviour)
- Apathy
- Loss of speech
Freud’s theory
Paranoid delusions result from repressed sexual urges which are striving for expression
Genetics- twins
45% concordance rate for schizophrenia in monozygotic twins (identical). 10% for dizygotic twins.
Shows that genetics does have an influence, but there must be factors other than genes
Stress
Study shows that bullying increases psychotic symptoms
Anti-psychotic drugs- Chlorpromazine
Originally marketed as an anti-histamine
Surgeon noticed it calmed normal patients when used as an anti-inflammatory
Decided it might calm schizophrenics and it did
Chlorpromazine block dopamine (DA) receptors so stops the DA working
Reserpine
Taken from snake root plant
Used to treat mental illness in India
Also effective in treating schizophrenia
Depletes vesicles so reduces amount of DA that can be released
Similarities
Both take 2-3 weeks to work
Symptoms present in Parkinson’s disease started to emerge
It was then discovered that Parkinson’s disease was due to a loss of dopamine in the nigro-striatal pathway
Dopamine theory
Drugs that reduce dopamine neurotransmission reduce psychotic symptoms
Drugs that increase dopamine neurotransmission can produce psychotic symptoms
The efficacy of an anti-psychotic drug is correlated with its ability to bind to DA receptors
Cocaine and amphetamine psychosis
Block reuptake- therefore leave more DA in the synapse
Found that there are 2 types of Dopamine receptors
D1 and D2, anti-psychotics that bind to D2 receptors are more efficient at treating schizophrenia
D1- positively coupled to adenylate cyclase
D2- negatively coupled to adenylate cyclase
AC is an enzyme that helps send messages inside the cell
