Working memory and Wisconsin Card Sorting Test performance in schizotypic individuals: a replication and extension

The present study examined spatial working memory and Wisconsin Card Sorting Test (WCST) performance in psychosis-prone individuals, either those with extremely high scores on the Social Anhedonia Scale (SocAnh; n = 49) or deviant scores on the Perceptual Aberration-Magical Ideation Scales (Per-Mag; n = 66). Sixty-three individuals with normal scores on the Chapman Psychosis-Proneness Scales served as control subjects. In order to evaluate working memory performance, participants were administered three tasks, namely, sensorimotor, degraded stimulus, and delayed-response tasks. Although the SocAnh and Per-Mag groups displayed poorer performance than control subjects on the working memory task, they did not differ significantly from each other. The SocAnh group exhibited slower reaction times on the working memory task compared to the control group. The groups did not differ in their performance on sensorimotor or degraded stimulus control tasks. Both psychosis-prone groups differed significantly from control subjects in terms of their WCST performance. Working memory performance was inversely associated with the number of perseverative errors (r = -0.17) and the number of trials to complete the first category on the WCST (r = -0.15). These findings extend the literature by indicating that some psychosis-prone individuals with social-interpersonal schizotypal deficits also display subtle spatial working memory impairments. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.