Smooth pursuit eye tracking and visual fixation in psychosis-prone individuals

Subjects identified by Perceptual Aberration-Magical Ideation (Per-Mag) sco res (n = 97), Social Anhedonia (SocAnh) scores (n = 45), and Physical Anhed onia (PhysAnh) scores (n = 31) as well as normal controls (n = 94), underwe nt psychophysiological and clinical assessment. This is the first published investigation of pursuit system functioning in three groups of questionnai re-identified at-risk individuals. Pursuit during a simple non-monitor trac king task was measured using root-mean-square error (RMSE) scores and pursu it gain scores. Fixation performance was measured in terms of number of sac cades away from the central fixation point. The at-risk subjects were more likely to display aberrant smooth pursuit tracking than controls, though th ere were no significant differences between the at-risk subjects endorsing items relevant to positive-symptom schizotypy and those endorsing items per taining to negative-symptom schizotypy. The groups did not differ significa ntly in their visual fixation performance. Participants were also evaluated for the presence of Axis I symptomatology and psychotic-like experiences. Neither the experimental subjects nor the control subjects displayed a sign ificant association between ocular motor performance and psychotic-like exp eriences. These findings are consistent with prior evidence that pursuit tr acking is a trait characteristic, independent of clinical status. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.