BRAIN CHANGES AND NEGATIVE SYMPTOMS IN SCHIZOPHRENIA

Negative symptoms (and cognitive impairments) in schizophrenia are a correlate of early onset and poor outcome. It is plausible that they are related to an arrest of brain development, for which there is now considerable evidence, but the precise relationship is elusive. In one post-mortem study negative symptoms were related to a reduction in brain length and in an MRI study to an asymmetry of sulcal CSF. It is proposed that the phenomena of psychosis (including negative symptoms) can be understood as part of the diversity of human personality structure generated by a process of sexual selection acting on a sexual dimorphism for cerebral asymmetry.