Overview of neuropathological theories of schizophrenia: From degeneration to progressive developmental disorder

Based on a review of literature three main hypotheses on the neuropathology of schizophrenia are identified: (1) neurodegeneration, (2) a disorder that is limited to the early development of the brain, and (3) a progressive developmental disorder. Research findings and clinical observations present evidence that the neurodegeneration hypothesis can be considered inaccurate; they also present several arguments against a disorder that is confined to early development. They are compatible, however, with a progressive developmental disorder. The hypothesis that schizophrenia is a disorder of developmentally reduced synaptic connectivity can account for important aspects of schizophrenia and gives an argument for further research into the possibilities and results of early treatment and perhaps even treatment prior to the first psychotic episode.