Effects of Muscle Vibration on Independent Finger Movements

Abstract

Previous studies had demonstrated that small amplitude muscle vibration (MV) could increase the motor pathway excitability of the vibrated hand muscle and inhibit the excitability motor pathways of neighboring muscles in healthy individuals. The purpose of this study is to examine whether the vibration-induced neurophysiological changes reflect in the voluntary control of finger movements. We tested the hypothesis that MV to individual hand muscle (abductor pollicis brevis, APB; first dorsal interosseus, FDI; or abductor digiti minimi, ADM) affects the control of finger abduction/adduction. Each fingertip position was captured using a motion capture system during four experiment conditions: no MV, MV to APB, MV to FDI, and MV to ADM. Two consecutive 10-s trials in each condition were tested for each finger. We calculated individuation index (find) and index of selective activation (ISA) to compare finger independency with and without MV. The results indicated that muscle vibration could enhance the independency of finger movements.