INFORMATION-PROCESSING MARKERS OF VULNERABILITY TO SCHIZOPHRENIA - PERFORMANCE OF PATIENTS WITH SCHIZOTYPAL AND NONSCHIZOTYPAL PERSONALITY-DISORDERS

Deficits in performance on tests of information processing have been p roposed to be markers of vulnerability to schizophrenia. Very few of t he previous studies of these information-processing deficits, however, have examined subjects who have clinical diagnoses of schizotypal per sonality disorders; most studies instead have focused on schizophrenic patients and their relatives or subjects selected on the basis of psy chometric evidence of schizotypal traits. In this study, patients with DSM-III schizotypal (n = 29) and non-odd cluster (n = 33) personality disorders were examined with the Continuous Performance Test (CPT) an d a backward masking test and compared with a group of normal voluntee rs (n = 31). Patients with schizotypal personality disorder manifested a specific deficit in performance, making significantly more errors o f omission in the degraded stimulus condition of the CPT compared with the nondegraded condition, whereas non-odd cluster patients and the n ormal volunteers performed the same in both conditions. No differences in performance between the groups were found for any of the backward- masking measures. These data suggest that specific deficits in CPT per formance, possibly reflecting reduced processing capacity or load resp onsiveness of the vigilance system, are associated with schizotypal pe rsonality disorder and fail to replicate previous studies finding back ward-masking deficits in various nonclinical schizotypal populations.