Negative and positive dimensions of schizotypal personality disorder

The positive (perceptual-cognitive) and negative (social-interpersonal) dimensions of schizotypal personality traits were examined in biological relatives of individuals with Axis I disorder. The subjects were young adult offspring from three contrasting parental groups, including schizophrenic disorder, affective disorder, and normal controls. Cognitive correlates, including digit span (presumed to assess working memory) and P3 amplitudes, were also examined. Preliminary results showed that positive and negative dimensions were distinguished by different prevalence patterns in the offspring subjects, and by a different pattern of correlations with cognitive measures. Negative dimensions were more frequent in offspring from the schizophrenic parental group than in the offspring from affective disorder and normal control parental groups. Digits forward and backward, and P3 amplitude decrements, characterized a subset of offspring with negative features from the schizophrenic parental group. Positive dimensions did not differ between the psychiatric parental groups, and did not covary with digit span or P3 amplitude assessments. These results support the view that positive and negative dimensions may reflect separable pathophysiologic processes.