Embodiment of an Avatar with Unnatural Arm Movements.

We developed an "unnatural avatar" of which the lower arms could be bent in reversed/unnatural directions. Participants controlled the avatar in a virtual environment to perform reaching tasks. We measured their senses of body ownership and agency. Compared to a normal avatar, the embodiment towards the unnatural avatar was significantly lower. However, senses of body ownership and agency towards both avatars were higher when the avatar's movements were synchronized with the movements of the participants compared to when there was a delay of one second. These results suggest that visuo-motor synchrony induces embodiment even towards avatars with reversed/unnatural limb movements.