[Saccadic reaction times and visuospatial disorders of attention in schizophrenic patients with negative symptoms]

Schizophrenics display various oculomotor disturbances. In this study we investigated saccadic reaction times in 47 unmedicated schizophrenics (ICD-9) as well as 28 age and sex matched normal controls. Using a cluster analysis according to the BPRS we determined two subgroups each with high and low negative symptoms; we expected poorer results from patients with negative symptoms on account of existing attentional deficits. The eye movements were recorded with electrooculography. Stimuli were presented at random with amplitudes of 5 degrees at a minimum and 20 degrees maximally; the distances between the angles were kept as short as possible, and we chose a fast stimulus rate (800, 1.000 and 1.200 ms). Only the group of schizophrenics with pronounced negative symptoms showed significantly delayed saccadic reaction times, whereas other schizophrenic patients did not differ from the controls. An unfavorable course of the illness also was associated with delayed reaction times. The saccadic reaction times were delayed in both the right and left visual field to the same degree. The poorer performance of the schizophrenics with pronounced negative symptoms are being discussed in relation to attentional deficits regarding visuospatial functions.