Professor James Watson notes that a feature of the schizophrenic brain is a smaller prefrontal cortex. This may relate to difficulties in problem-solving.
The most devastating feature of schizophrenia, one for which none of the medicines really work, is a diminished prefrontal cortex. That is, schizophrenics find it very hard to plan ahead, to really think about the future. When measured by IQ tests, the IQ of a schizophrenic is generally fifteen points lower than it would be without the disease. There would be some who would normally have very high IQs, but it’s always diminished.
Kraepelin, one of the early investigators of schizophrenia called it Dementia Praecox, as if there was a dementia taking place. So, the most awful feature of schizophrenia is just the inability of the brain just to function – its learning.
So, what we want to find is, what goes wrong with the learning process, why doesn’t the prefrontal cortex function? The ability for people with schizophrenia to solve puzzles is really diminished, their ability to recognize faces, or vocabulary, is diminished, but not to the same extent as just problem-solving.