Biochemical Influenes

Question 0

Evaluation

Answer 0

Unknown if sensitivity to dopamine is cause or consequence.
Excessive dopamine can cause ventricular enlargement.
Dopamine inhibiting drugs take minutes to take effect but a few weeks before effects are seen so not directly responsible.
Phenothiazines have to reduce dopamine below normal levels to the levels of Parkinsonism if they’re to be effective.
Reducing to normal levels should be effective.
Atypicals block fewer dopamine receptors than older drugs but are just as effective.
Oestrogen appear to offer some protection, possibly explaining the lower schizo diagnosis in teen girls.

Question 1

Dopamine Hypothesis

Answer 1

Phenothiazines (drugs that inhibit dopamine activity in the brain) reduce the symptoms of schizo.
L-dopa (synthetic drug that releases dopamine) produces symptoms of paranoid schizo.
Anti psychotic drugs taken by schizos can produce Parkinsonism (opposite of schizo and too little dopamine).
Prolonged cocaine releases dopamine and can produce temp psychosis.
Post mortems of schizos show increase of dopamine in left amygdala and increased dopamine receptor density.
Not always replicated though.