biological explanations - dopamine hypothesis ao1

Question 1

what is dopamine and its role?

Answer 1

• dopamine is a nurotransmitter
• in the brain which causes neurons to fire

Question 2

what is the dopamine hypothesis?

Answer 2

schizophrenia is caused by an excessive amount of dopamine
- this causes neurons that use dopmaine to fire too often and transmit too many messages

Question 3

what does a high level of dopamine lead to?

Answer 3

• acute episodes and positive symptoms (delusions, hallucinations)

Question 4

Evidence for this comes from the fact that amphetamines increase the amounts of dopamine…

Answer 4

• Large doses of amphetamine given to people with no history of psychological disorders produce behaviour which is very similar to paranoid schizophrenia.
• Small doses given to people already suffering from schizophrenia tend to worsen their symptoms.

Question 5

there are more dopamine receptors…

Answer 5

• More receptors lead to more firing and over production of messages.
• Autopsies have found that there are generally a large number of dopamine receptors (Owen et al., 1987) and there was an increase in the amount of dopamine in the left amygdale (falkai et al. 1988) and increased dopamine in the caudate nucleus and putamen (Owen et al, 1978).