Biological Theory of Schizophrenia

Theory

Schizophrenia is caused by brain dysfunction in the brain. The brain plays a large part in controlling our cognitions and behaviour, so when its function or structure is different then our thoughts and actions are abnormal.

Biological cause for schizophrenia

Overactive Dopamine System → More dopamine neurotransmitters passing through synapses →Caused by dopaminergic neurons firing too easily and too many dopamine receptors showed in brain scans of people who have schizophrenia.

Cause and effect

It would make sense that dopamine activity is a cause of schizophrenia, as dopamine controls movement, perception and mood and schizophrenia symptoms include abnormal movement, percieving things or believing things that do not exist, and fluctuations in mood.

Causes of brain dysfunction

Gene defects or problems whilst the foetus’ brain is still developing could cause brain dysfunction. The symptoms of schizophrenia develop as the person matures.

People who have schizophrenia are shown to have these differences in their brain (4)

The volume of the brain is around 5 percent lower than the average human brain

The frontal lobes are less active due to less blood flow

Temporal lobes lack grey matter

The hippocampus is smaller than average

Criticisms

Problems establishing cause and effect

Focuses too much on nature

Too reductionist