Smooth pursuit eye movements of schizophrenics and normal people under stress

Eye movements while watching an oscillating pendulum were recorded in 24 chronic schizophrenies and 24 matched normal controls. As others have reported previously, abnormal tracking movements were significantly commoner in the schizophrenics. However, in a series of experiments with normal subjects it was found that conditions designed to distract attention, or to produce declining arousal and attention, produced abnormal tracking movements indistinguishable from those observed in schizophrenics. As chronic schizophrenics are known to perform badly on a variety of psychomotor tasks and there is evidence that this is due to impaired attention or heightened distractibility, it seems likely that these same factors are responsible for their poor eye-tracking performance.