Eye-head synkinesia in schizophrenic adults during a repetitive visual search task

This study investigated the role of head movements in the functional visual field of three groups of schizophrenics and a normal control group during the performance of a repetitive visual search task. The experimental apparatus consisted of a semicircular panel with six columns of lights extending up to 90 degrees to the right of the subject's initial visual fixation point. The task involved identifying which column contained an extra light by pressing the appropriate response key. A string connected to a potentiometer measured head movements. All schizophrenic groups showed an excess of head movements in comparison to controls, reflecting abnormal coupling of head and eye movements. These results confirm previous anecdotal reports in schizophrenic adults and extend findings in schizophrenic children, which have been interpreted as reflecting maturational lag of the nervous system.