Saccadic eye movements in psychiatric patients.

Saccadic eye movements were examined in 110 psychiatric patients and 26 controls, evaluating three parameters, the frequency of dysmetric saccades, nonfixation and the saccadic reaction time. Dysmetric saccades (dysmetria) were defined as saccadic reactions undershooting the target, nonfixation was defined as a deviation of the gaze from the target with the target stationary. While the nonfixation score and the saccadic reaction time were slightly increased in most of the psychiatric patient groups as compared to controls, an increase of the dysmetria score was confined to patients with schizophrenic and schizoaffective disorders. Dysmetria is thus interpreted as the expression of a relatively specific impairment of attention in these patients.