Combining mediated social touch with vision : from self-attribution to telepresence?

Combining mediated social touch (i.e., interpersonal touch over a distance by means of a tactile display) with vision allows people to both see and feel their remote interaction partner’s touches. This is expected to increase the user’s sense of telepresence (i.e., the experience of "being there" in the same environment as one’s remote interaction partner), thereby perhaps providing part of the imediacy that marks natural unmediated physical contact. Such a possible effect of combining touch with vision is expected to depend partly on the central nervous system’s ability to categorize tools and technological artifacts as an actual part of one’s body. Since such so-called self-attribution is facilitated by a morphological congruence between the artifact and the human body, we anticipated that the effect of combining touch with vision would be larger when people could see the mediated touches being performed on a morphologically congruent as compared to an incongruent input medium. In our experiment, we compared two input media: a sensor-equipped mannequin that enabled a one-to-one mapping between seen and felt touch, and a morphologically incongruent touch screen that displayed a set of buttons. When participants saw the touches being initiated on the morphologically congruent mannequin input medium, they, as expected, reported a higher sense of telepresence. In addition, they perceived of the mediated touches as more touchlike with the mannequin as compared to the touch screen input medium. These findings illustrate that visual feedback, especially when morphologically correct, can improve mediated social touch. Our experiment, however, suggests that other mechanisms than self-attribution might be involved.