A proposal of a rehabilitation method for elderly people having poor equilibrium sense using visual and auditory stimulation

Our goal is to develop a visual and auditory stimulation system to improve the poor sense of balance of the elderly. We examine how visual and auditory stimulation contribute to improve the poor sense of balance. We have investigated the effectiveness of a rehabilitation system using visual and auditory stimulation. First, we studied the influence of visual stimulation on postural control by measuring a sway of the center of gravity and head positions of subjects experiencing optokinetic stimulation. The subjects were healthy young males. The experiment was performed in a quiet and dark room. A random dot screen was used for the optokinetic stimulation. The experimental results show that the sway of the center of gravity and head position was about 1.3 times greater when optokinetic stimulation was used than when it was not. Next, we investigated the influence of auditory stimulation on postural control by measuring the sway of their centers of gravity. In this experiment, a sound image was rotated around the subject through speakers which produced white noise. From the result, the sway of gravity center increased when the sound image was rotated. This demonstrated much the same characteristics as visual stimulation. This means that the sways of the head position and the gravity center increase when either visual or auditory stimulation are moved. We conclude that moving visual and auditory stimulation may control the sense of balance. Therefore, a rehabilitation method using visual and auditory stimulation would be useful for improving a poor sense of balance.