Eye tracking in relation to age, sex, and illness.

Impaired eye-tracking performance in psychotic patients has been previously demonstrated. Nine groups of ten patients each were used to determine if, when equated for age and sex, some of the eye-tracking dysfunction observed by others could be alternately explained in terms of aging, sex, or the presence of Parkinson-like symptoms. Horizontal eye tracking was recorded while patients visually tracked a target moving at 5degrees/sec and 20degrees/sec. Both sinusoidal and triangular target movements were used. Results indicated that Parkinson patients were the poorest eye trackers and that young normal men were the best. Additionally, men were better eye trackers than women and normal controls were better eye trackers than were schizophrenic patients or their parents.