Neural explanations for Schizophrenia A03

Question 1

What is the evidence which shows that dopamine is involved in Sz? (There are 3 pieces of evidence)

Answer 1

The role of Amphetamines found by Curran 2004:
They increase dopamine and they:
A) worsen symptoms of Sz in those diagnosed with it
B) induce symptoms in people without Sz

Antipsychotic drugs found by Tauscher 2014:
Which reduce dopamine activity, which reduces the intensity of Sz symptoms

Candidate genes:
Found to be linked to Sz, either act on the production of dopamine or the production of dopamine receptors on the synapses

Question 2

Why is lots of evidence which supports the role of glutamate in Sz a limitation of neural correlates?

Answer 2

Post mortems and brain scans have shown consistently raised levels of the neurotransmitter glutamate in patients with Sz (McCutcheon 2020)

This is a limitation of the dopamine hypothesis because it shows that there are other explanations/neurotransmitters involved - hypothesis is incomplete

Question 3

What did Catherine Tenn (2013) do and find?

Answer 3

Induced Sz symptoms in rats using amphetamines and then relieved the symptoms using drugs which lower dopamine.

This seems to support the dopamine hypothesis.

Question 4

What did Depatie and Lal 2001 find?

Answer 4

Other drugs which increase dopamine, such as ‘apomorphine’ do not cause Sz like symptoms, showing conflicted evidence.