P33. Noisy galvanic vestibular stimulation improves dynamic walking stability in healthy subjects

Introduction We examined the effect of galvanic vestibular stimulation (GVS) delivered as zero-mean white noise current (noisy GVS) on the walking performance in healthy subjects. Methods The walking performance of 15 healthy subjects (mean age 23.0 ± 1.3 years) at slow, preferred and fast walking speed was examined during two different conditions: (1) walking with eyes closed and zero amplitude sham noisy GVS, and (2) walking with eyes closed and non-zero amplitude noisy GVS set to 80% of the individual sensory threshold for GVS. We examined 10 gait parameters: stride time, stride length, base of support, swing time percentage, double support time percentage as well as the CV of stride time, stride length and base of support, gait asymmetry and bilateral phase synchronization. Results Noisy GVS significantly improved stride time CV by 34% ( p p p p p Conclusion Noisy GVS is effective in improving locomotion function in healthy subjects. It predominantly targets the variability and bilateral coordination characteristics of the walking pattern, which are critically linked to dynamic walking stability. The predominant impact of noisy GVS during slow walking supports the principle of a speed-depended role of sensory feedback in locomotion control.