Visual Influence on Center of Contact Pressure in Advanced Parkinson's Disease

Abstract The visual influence on upright posture was studied in seven patients with Parkinson's disease (PD), Yahr stage III to IV, and seven age-matched controls. The position of the center of contact pressure (CCP) between the feet and floor was analyzed by a photoelastic method. When the patients' eyes were closed, the CCP position shifted significantly backward in PD (open, 48.6 ± 7.6%; closed, 45.0 ± 4.8%; p p p p