Touch, tools, and telepresence : embodiment in mediated environments

We tend to think of our body image as fixed. However, human brains appear to support highly negotiable body images. As a result, our brains show a remarkable flexibility in incorporating non-biological elements (tools and technologies) into the body image, provided reliable, real-time intersensory correlations can be established, and artifacts can be plausibly mapped onto an already existing body image representation. A particularly interesting and relevant phenomenon in this respect is a recently reported crossmodal perceptual illusion known as the rubber-hand illusion (RHI). When a person is watching a fake hand being stroked and tapped in precise synchrony with his or her own unseen hand, the person will, within a few minutes of stimulation, start experiencing the fake hand as an actual part of his or her own body. In this paper, we will review recent work on the RHI and argue that such experimental transformation of the intimate ties between body morphology, proprioception and self-perception enhances our fundamental understanding of the phenomenal experience of self. Moreover, it will enable us to significantly improve the design of interactive media, including the design of avatars in virtual environments and digital games, as well as a range of human-like telerobotic devices.