Influences of visual feedback indicator scales on human upright postural control

Human upright postural control is highly related to visual information. In order to investigate the influence of visual feedback on static upright postural control, postural sway of eight healthy adults was investigated under visual feedback circumstances. In the investigation, postural feedback information was visualized by an indicator composed of a movable spot and a stationary circle, and postural control of subjects was inspected both in time domain and frequency domain. The experiment results indicate that reduction of the visual feedback indicator scale inspires a postural power shift to the higher frequencies, and this reduction also induces a fall-after-rise pattern of postural energy distribution in the frequency range of 0.5~1 Hz.