JMIR Publications

ABSTRACT

Background:

The sense of embodiment (SoE) is the feeling of one’s own body, and research on the SoE has been extended from the rubber hand illusion to the full-body ownership illusion with virtual avatar.

Objective:

The key to utilizing virtual avatar is understanding and controlling the SoE, and it can be extended to several medical application. In this study, we aimed it by considering three subcomponents of SoE: sense of agency, ownership, and self-location.

Methods:

We defined a human avatar (HA), point light avatar (PLA), and out-of-body point light avatar (OBPLA) and compared them with three user studies. In study 1, twenty-eight participants were recruited and compared three avatar conditions (HA, PLA, and OBPLA). In study 2, twenty-nine new participants were recruited and there were two avatar conditions (HA ad PLA) and two motion synchrony conditions (Synchrony and Asynchrony). In study 3, twenty-nine another participants were recruited and there were two avatar conditions (PLA and OBPLA) and two motion synchrony conditions (Synchrony and Asynchrony). Dependent measures included sense of agency, ownership, and self-location, emotional response, presence, and simulator sickness.

Results:

The findings of first study showed that the three avatar generation methodologies can control the sense of ownership and self-location in a stepwise manner while maintaining a high sense of agency. In the second and third studies, we found dependencies among the three subcomponents of SoE, and observed that they affected users’ subjective experiences.

Conclusions:

Our findings may have implications in boosting the effects of virtual avatar applications to medical areas, by understanding and controlling the SoE with the full-body illusion.