Evaluate

• By only focusing on nature, the theory ignores the effect of nurture on the development of SZ 


  even if evidence shows that the brain of people with SZ look and work differently, this is not enough to cause the disorder by itself. The brain still needs to interact with what is happening in the environment to be able to produce symptoms like hallucinations, delusions and disorganised speech.
• It is possible that brain dysfunction is an effect of SZ not its cause

  because a lot of evidence comes from investigating the brain in post modems or scans after the diagnosis we cannot be sure what came first. Brain function and structure may change after something else has triggered the disorder (brain dysfunction could be a symptom).
• Critics say that the biological theory is too deterministic 


  SZ may not be completely controlled by what is happening in the brain. People may choose to let their symptoms take over rather than control them. Pessimistic to see people with SZ having no free will – can people with SZ really not control their disorder at all?
• Critics say that the biological theory is too reductionist 


  it is too simplistic to try to explain such a complex disorder by just looking at a part of the brain or one neurochemical. A number of different factors may be working together to cause SZ.
• For some psychologists SZ is too broad a label that covers a diversity of symptoms 


  may not be realistic to look for a biological cause that maybe partially constructed by society.