Effect of visual information on postural control in patients with schizophrenia

Lateralized motor and attentional abnormalities contribute to schizophrenia, but little is known about possible abnormalities in neural machinery involved in postural control. We examined postural stability of 22 patients with schizophrenia taking medication and 14 healthy control participants using computerized force platform posturography. The shift in the center point of pressure in the condition of eyes open versus eyes closed characterizes the effect of visual information on body posture. Closing the eyes had less of an effect on the center point of velocity (velocity sm/s) in the patients with schizophrenia than in the control group (median change, 36% vs. 70%, p = 0.0006). Change in the body position during eye closure tended to be directed rightwards in the control group but leftwards in the group with schizophrenia (p = 0.025). The results show that visual component had less dominance in the balance control of these patients with schizophrenia. The lateralized effect of visual information on posture was also impaired.