Facilitation of finger movement learning by body ownership illusion

Abstract

Imitation is commonly observed in various motor learning. Although it is a computationally difficult problem that involves solving self-other correspondence problem and calculating appropriate motor commands that reproduce the observed motion, human adults and children seem to be somehow able to effectively perform this process. In this study, we have found that imitative motor learning of a sequential finger movement, similar to piano playing, can be facilitated when the learner is under the body ownership transfer illusion. We presented a computer-generated animation of a hand performing the movement as the instructor, and induced the illusion by visuo-tactile stimulation using a moving computer-generated cone-shaped object and a vibration motor. We tested two conditions, synchronized and unsynchronized visuo-tactile stimulation, and found that the learning was significantly improved when synchronized stimulation was given. The result suggests existence of a common mechanism shared by both perception of body ownership and imitative motor learning.