There are two explanations which can be placed under the umbrella term of ‘psychological explanations’, the psychodynamic and cognitive approaches.
The psychodynamic explanation
Freud believed that schizophrenia is caused by issues in the sub-conscious mind of the schizophrenic. If someone experiences something particularly harsh they may regress to a childlike state, before the ego was fully formed. This childlike state is what brings about the symptoms; delusions, grandeur etc.
Evaluation of the psychodynamic explanation
The only real strength of the psychodynamic explanation is that it has face validity; the symptoms of schizophrenia do seem similar to some childlike behaviour.
However, there are many weaknesses of this explanation; for example, there is no research to support Freud’s work in terms of schizophrenia. This is partly because the theory is based upon abstract ideas such as dreams and the subconscious.
Stirling and Hellewell suggest that the schizophrenic behaviour isn’t similar to an infants, this contradicts Freud’s theory.
The cognitive explanation
This explanation says the schizophrenia is caused by faulty thought processing. An example of this could be that a person experiences senses that aren’t real, so they turn to other people to confirm that this sense is real. However, when the people around tell him that this ‘sense’ isn’t real the person feels that everyone else is conspiring against him. So, due to faulty processing, the simple problem of mistaking something unreal for something real has lead eventually to paranoia.
This explanation doesn’t discount the biological explanation; after all, there must be some biological wrong in the first place to create the incorrect reality. Instead it builds on the biological model, and offers an explanation on how the problems can develop into schizophrenia.
Evaluation of the cognitive explanation of schizophrenia
There is a wealth of research evidence to back up the cognitive explanation. For example, Meyer and Lindenberg found a link between excess dopamine in the prefrontal cortex, and the state of working memory. This suggests that there is a scientifically proven link between faulty processing, and high dopamine levels. This supports the connection between the biological and cognitive explanations.
Another strength of this explanation is that it allows us to develop treatments. For example, Yellowlees et al created a machine that creates virtual hallucinations, the sort that a schizophrenic might experience. The aim of this machine is show schizophrenics that their hallucinations are not real. Whilst there is little evidence that this will work, it has only been possible because of the cognitive explanation.