Effects of the Number of Bodies on Ownership of Multiple Bodies

Virtually reality can induce body ownership (Sense of being one’s own body) of a not innate body or multiple bodies. However, the relationship between the number of bodies and body ownership has not been clarified. In a study that investigated body ownership for one, two, and four virtual bodies, the greater the number of bodies, the closer the body ownership tended to approach the strength of ownership for a single body. Therefore, in the present study, we investigated whether increasing the number of bodies strengthens body ownership for multiple bodies. In the experiment, multiple virtual bodies that moved in synchronization with the participant’s movement were lined up in a single file line, and the participant observed the multiple virtual bodies through a head-mounted display from the position of the hindmost virtual body. We measured body ownership and drifts in self-location. Our results showed that contrary to expectations, the greater the number of bodies, the weaker body ownership.