Purpose The purpose of this study was to investigate the effect of auditory stimulus using white noise on stability and balance during sit-to-stand and standing tasks of chronic stroke patients. Methods Eighteen chronic stroke patients participated in this study. They asked to perform the tasks of sit-to-stand, standing with eyes open and standing with eyes closed before and after listening to white noise. Eight infrared cameras and one force plate were used to evaluate the stability and balance before and after the white noise stimulus during each task. Results There was no significant difference between before and after white noise stimulus in all tasks. On the other hand, the anteroposterior range of CoP was significantly decreased after white noise stimulus in standing with eyes-closed (p<.05), and the sagittal angle of CoP-CoM was significantly decreased after white noise stimulus in standing with eyes-open and eyes-closed (p<.05). Conclusion Auditory stimulus using white noise improves the balance of chronic stroke patients. Therefore it is thought to be helpful for the independent daily life of chronic stroke patients.
Purpose The purpose of the study was to investigate the effect of vibratory stimulus on the static postural control of 8 healty senior adults. Methods To achieve this goal, all subjects participated in two different kinds of static postural control tasks. Task 1 was a static postural control task, where both-legs stand on the ground. Second task was an unstable static postural control task using only single leg stance. As they maintain their balance, 6 different vibratory stimulus were provided on the sole of their feet(personal threshold 0%, 80%, 90%, 100%, 110%, 120%). Results The results of the study were as follows: First, there was no significant differences in postural control ability according to different types of vibrator intensity. Second, there was a significant difference in single-leg postural control ability according to vibrator intensity. Third, there was a significant difference in anterio-posterior stability according to the different types of vibrator intensity. Conclusion Stochastic resonance using vibratory stimulus was more effective in the single leg stance task, rather than the double leg stance task. Moreover, sub-threshold vibratory stimulus(80%, 90%) intensity were more effective than higher vibratory stimulus(100%, 110%, 120%).
