Voluntary self-tapping induces self-localization shift

Abstract

Rubber Hand Illusion (RHI) is known to provide a proprioceptive drift toward the direction where the rubber hand is tapped. On the other hand, Out-of-Body Experiences (OBEs) induce an entire body shift from a third-person Point of View (PoV) . These experiences are known to trigger external passive tactile cues. Telexistence allows an entire body shift from a first-person PoV, compared to RHI and OBE. However, the precise origin of the entire localization is not revealed when we actively provide the internal voluntary tactile cue. Therefore, in this paper, we focus on the effects of tactile cues to determine self-localization during the action of self-tapping. Participants viewed and tapped their own body on the back, and evaluated where on their body they perceived the tapping. The experiments show that the localized position tends to shift forward when an individual is tapped by a third-person; in contrast, the localized position tends to shift backward when an individual is tapping his own back. The subjective report indicates that participants perceived themselves as leaving their own bodies, or that someone appeared in front of them suddenly. Thus, we consider that self-produced tactile cue induces telexistence experience.