Abnormalities of auditory event‐related potentials in students with schizotypal personality disorder

Biological, phenomenological and cognitive similarities are known to exist between schizophrenia and schizotypal personality disorder (SPD). This study examined whether, and to what extent, abnormalities in event‐related potentials (ERPs) already extensively reported in schizophrenia can also be observed in persons psychometrically identified with SPD. Event‐related potentials were examined in nine SPD subjects and nine controls recruited from among 1693 college students, using the Schizotypal Personality Questionnaire (SPQ) and the Structured Clinical Interview for DSM‐III‐R (SCID I and II). Event‐related potentials were recorded during an auditory oddball task. Smaller P300 amplitude and prolonged P300 latency were found in SPD subjects as compared with controls. Our findings indicate that such individuals do have deficits in information processing similar to that found in schizophrenia. We can conclude that P300 abnormalities may not be specific for SPD but that abnormalities shown in SPD are possibly a vulnerability marker for developing schizophrenia.