Biochemical Factors Of Schizophrenia

Question 1

What do Phenothiazines do?

Answer 1

They are drugs which act by blocking dopamine at the synapse, and are affective in alleviating some of the major symptoms of schizophrenia

• Phenothiazines tends to only alleviate the positive symptoms and not the negative symptoms
• counter argument: there are different types of schizophrenia and these might have different underlying causes

Question 2

What does L-dopa do?

Answer 2

A drug used to treat Parkinson’s disease, acts by increasing dopamine levels. It can produce symptoms of schizophrenia in previously unaffected individuals

• L-dopa do not worsen symptoms in all people diagnosed with schizophrenia
• Cause and effect can’t be established - research may be correlational (high dopamine levels in schizophrenics) but it can be argued that excess dopamine is an effect of rather than the initial cause.
• drugs may not be the right way to treat if dopamine isn’t the cause, however since anti-psychotics do work it can be argued that high dopamine levels are the cause

Question 3

What did Seeman (1987) find?

Answer 3

Reviewed a number of studies which found increases in dopamine receptor density between 60 and 110% schizophrenics compared to controls.

• such examinations were carried out on people who had taken neuroleptic drugs for years and so it is difficult to tell whether increased dopamine levels are the result of drug therapy rather than the cause of schizophrenia

Question 4

What does the dopamine hypothesis suggest?

Answer 4

It suggests that schizophrenia results from an excess of dopamine activity at certain synaptic sites.
An excess of dopamine activity can be caused by the release of excess dopamine by pre-synaptic neurones, an excess of dopamine receptors or over-sensitivity of dopamine receptors

To argue that an imbalance in neurotransmitters is the only cause of schizophrenia is reductionist