EXPRESS SACCADES AND SMOOTH-PURSUIT EYE-MOVEMENT FUNCTION IN SCHIZOPHRENIC, AFFECTIVE-DISORDER, AND NORMAL SUBJECTS

Saccadic and smooth pursuit eye movements were recorded in three groups of subjects: a schizophrenic group, a non-schizophrenic psychotic patient comparison group, and a normal control group. Schizophrenic subjects demonstrated a greater decrease in saccadic response time than did normal controls in a gap task (when the fixation point was turned off 150 msec before the target appeared). The psychiatric comparison subjects did not differ from normal controls. Further, only schizophrenic subjects demonstrated a relation between smooth pursuit and saccadic eye movement performance, such that subjects with impaired smooth pursuit showed a larger decrease in saccadic response time in the gap task. The relation between performance on the gap task and quality of smooth pursuit and its relevance for a prefrontal deficit hypothesis of schizophrenia are discussed.