Saccadic reaction times in acute and remitted schizophrenics

Abstract

Schizophrenics are known to have various disturbances of the visuomotor system. Whereas smooth pursuit eye movement disorders have been repeatedly confirmed, there are relatively few reports regarding possible disturbances of the saccadic system. In this study, the saccadic reaction times of 47 schizophrenic inpatients were investigated upon admission and later in the remitted state; 28 age- and sex-matched normal volunteers were tested as controls. Psychopathology and outcome were evaluated according to the Brief Psychiatric Rating Scale and the Prognostic Scale. Light stimuli were presented at random direction, location (ranging from 0° to 20°) and duration (800, 1000, and 1200 ms). The eye movements were recorded by electro-oculography. Compared with the control group, schizophrenics revealed prolonged saccadic reaction times, which correlated with pronounced negative symptoms and an unfavourable course of the illness. The saccadic reaction times remained prolonged in schizophrenic patients. These findings suggest attentional deficits in schizophrenics.