Combined Induction of Rubber-Hand Illusion and Out-of-Body Experiences.
Frontiers in Psychology January 1, 2012 Isadora Olivé, Alain Berthoz
Self-consciousness relies on body ownership (attributing self-identity to the body) and self-location (localizing the sense of self). The rubber-hand illusion (RHI) and out-of-body experience (OBE) are thought to target body-part and full-body representations separately, but their relationship is unclear. Using a virtual-reality task combining adapted RHI and OBE, a spatial dissociation between visual and proprioceptive hand feedback was created during rest or action. Proprioceptive drift of the left hand and shifts in subjective-straight-ahead (SSA) toward the manipulation side were equivalent in both conditions. The combined effect depended on visual representation of body parts, with no main or modulatory role for motor programs. This demonstrates a systematic relationship between body-part and full-body illusions, suggesting a common mechanism underpinning ownership and self-location.