I have read articles positing that psychosis causes brain damage and schizophrenia is a disease. I would like to say that episodes of fixed, clearly false beliefs (delusions) and false perceptions of reality (hallucinations) does not cause brain damage. A true belief which causes distress, because the patients friends or family disagree with it, does not cause brain damage, thus how can a false belief be the root of brain damage. It is clear that hallucinations are caused by chemicals in the brain, but how could a change in chemicals in the brain cause brain damage? There is no evidence that schizophrenia is a brain disease, like Alzheimers Disease. In fact schizophrenia is a disorder of thought, emotion and perceptions, rather than being a disease of a brain. A disease of the brain is indicated by a gradual collapse in functioning and speech. This is not seen in schizophrenia. In fact people diagnosed with schizophrenia, generally recover from the disorder, even without the aid of medications.
'Yet people with real brain disease - such as Alzheimer's, stroke, or a tumor - don't talk symbolically like [schizophrenics] do.' pg. 24 of Toxic Psychiatry
'Brain damaged people typically display memory difficulties..' from Toxic Psychiatry
'Advanced degrees of brain disease render the individual unable to think in such abstract or metaphorical terms [as schizophrenics do].' from Toxic Psychiatry
'Individuals with schizophrenia, including those who have never been treated, have a reduced volume of gray matter in the brain, especially in the temporal and frontal lobes. Recently neuroscientists have detected gray matter loss of up to 25% (in some areas). The damage started in the parietal, or outer, regions of the brain but spread to the rest of the brain over a five year period. Patients with the worst brain tissue loss also had the worst symptoms, which included hallucinations, delusions, bizarre and psychotic thoughts, hearing voices, and depression.'
from http://www.schizophrenia.com/disease.htm#significant
References
Peter R. Breggin, M.D. - Toxic Psychiatry