Effect of simultaneous vibrations to two tendons on velocity of the induced illusory movement

A typical prosthetic limb has sensory shortcomings, one of which is lack of kinesthesia. Conventional methods to evoke kinesthesia, which would be required for a precise control of prosthetic limbs, include tendon vibration and skin stretch, but these produce only the sensation of small movements. In this study, tendon vibration is extended to evoke sensations of a more rapid movement. A stimulation method in which vibration is applied to two tendons is proposed, in contrast to most studies in which a single tendon was vibrated. Experimental results indicated that vibration applied to both ends of a muscle produces sensations of more rapid movement than vibration to just one. However, no significant difference in sensation was found between vibrating tendons of synergistic muscles and a single tendon.