Body ownership and kinaesthetic illusions: Dissociated bodily experiences for distinct levels of body consciousness?

Seeing an embodied humanoid avatar move its arms can make an observer feel as though their own static arms are moving, treating the avatar's kinematic signals like those from a biological body. Two experiments showed that the sense of body ownership over an avatar seen from a first-person perspective was closely linked to visuomotor synchrony. However, kinaesthetic illusions did not depend on this synchrony, indicating that the avatar is inevitably processed at the sensorimotor level as one's own body, whether consciously considered as such or not. The findings suggest that body ownership and kinaesthetic illusions may be underpinned by distinct representations: the body image and the body schema.

Study at a glance

Abstract

Seeing an embodied humanoid avatar move its arms can induce in the observer the illusion that its own (static) arms are moving accordingly, the kinematic signals emanating from this avatar thus being considered like those from the biological body. Here, we investigated the causal relationship between these kinaesthetic illusions and the illusion of body ownership, manipulated through visuomotor synchronisation. The results of two experiments revealed that the sense of body ownership over an avatar seen from a first-person perspective was intimately linked to visuomotor synchrony. This was not the case for kinaesthetic illusions indicating that when superimposed on the biological body, the avatar is inevitably treated at the sensorimotor level as one's own body, whether consciously considered as such or not. The question of whether these two bodily experiences (body ownership and kinaesthetic illusion) are underpinned by distinct representations, the body image, and the body schema, is discussed.