EYE-MOVEMENT IMPAIRMENT AND SCHIZOTYPAL PSYCHOPATHOLOGY

Objective: Eye movement dysfunction in relation to a smooth pursuit ta sk has been documented in schizophrenic patients and in patients with the related personality disorder, schizotypal personality disorder. To investigate which quantitative measures are associated with the eye m ovement dysfunction and whether the dysfunction is more related to the psychotic-like or the deficit-like symptoms of schizotypal personalit y disorder, ratings of eye movements in several groups of subjects wer e compared. Method The study groups consisted of 26 patients with schi zotypal personality disorder, 42 patients with other personality disor ders (22 who also had two or more schizotypal personality traits and 2 0 who had fewer than two), and 37 normal comparison subjects. Smooth p ursuit eye tracking of sinusoidal and constant velocity targets was re corded by an infrared eye tracking system. Two raters evaluated pursui t gain and large and small saccades in the direction of the target and in the direction opposite to that of the target (quantitative ratings ) and constant velocity (qualitative rating). Results: Patients with s chizotypal personality disorder and patients with other personality di sorders and two or more schizotypal traits, but not those with fewer t han two schizotypal traits, had significantly poorer qualitative ratin gs of tracking than the normal comparison subjects. Neither gain nor a ny of the saccadic measures significantly differed between groups. The number of large Eye Movement Impairment and Schizotypal Psychopatholo gyEye Movement Impairment and Schizotypal PsychopathologyEye Movement Impairment and Schizotypal Psychopathologysaccades in the direction of the target was the only quantitative variable that predicted low, qua litative ratings. Qualitatively poor tracking was associated with the deficit-like, but not the psychotic-like, symptoms of schizotypal pers onality disorder. Conclusions: Patients with schizotypal personality d isorder demonstrate qualitatively poorer tracking than comparison grou ps, and the impaired tracking is associated with deficit-like symptoms .