Abnormal orienting in schizotypal personality disorder

Previous studies have found evidence for skin conductance (SC) orienting abnormalities in psychosis-prone subjects, but there have been no previous studies on subjects with a diagnosis of schizotypal personality disorder. This study assesses whether clinical schizotypal subjects show abnormal habituation to orienting stimuli. Thirteen subjects with both high scores on the Schizotypal Personality Questionnaire (SPQ) and a DSM-III-R clinical diagnosis of schizotypal personality disorder were compared to 30 controls with no such diagnosis and with low scores on the SPQ. While normals showed the expected habituation in SC orienting across trials, schizotypal subjects failed to show a decrement in responding across the first three trials. In a second study on 30 new subjects, individual differences in schizotypy correlated significantly (p = 0.47) and in the predicted direction with a dimensional measure of the orienting deficit. It is hypothesized that this retarded habituation in schizotypals reflects a deficit in preattentive template matching, which may in turn partly relate to the working memory and prefrontal deficits observed in schizotypal and schizophrenia patients.