The biological basis of schizotypal personality disorder

Schizotypal personality disorder is the DSM equivalent of the ICD category schizotypal disorder. It may be seen as part of the schizophrenia spectrum of disorders. Patients with schizotypal personality disorder (SPD) share many features with schizophrenic patients. These include symptoms of social isolation and cognitive impairment. They also share imaging and biochemical evidence of brain dysfunction, and genetic similarities. SPD patients, however, for some reason do not become chronically psychotic. The study of schizotypal patients is of great importance in attempting to clarify the genetic and biological basis of the schizophrenia spectrum. It is also important in helping to delineate the differences between schizophrenic and schizotypal patients, and to distinguish those factors that protect the schizotypal patient from becoming floridly psychotic. In this article we present recent findings regarding the biological basis of schizotypal personality disorder. We illustrate the contribution of these findings to our understanding of risk and protective factors in the schizophrenia spectrum.