Seeing and identifying with a virtual body decreases pain perception.

Division of Psychosomatic Medicine, Department of General Internal Medicine, Inselspital, Bern University Hospital and University of Bern, Switzerland.
European journal of pain (London, England) (Impact Factor: 3.37). 05/2011; 15(8):874-9. DOI: 10.1016/j.ejpain.2011.03.013
Source: PubMed

ABSTRACT Pain and the conscious mind (or the self) are experienced in our body. Both are intimately linked to the subjective quality of conscious experience. Here, we used virtual reality technology and visuo-tactile conflicts in healthy subjects to test whether experimentally induced changes of bodily self-consciousness (self-location; self-identification) lead to changes in pain perception. We found that visuo-tactile stroking of a virtual body but not of a control object led to increased pressure pain thresholds and self-location. This increase was not modulated by the synchrony of stroking as predicted based on earlier work. This differed for self-identification where we found as predicted that synchrony of stroking increased self-identification with the virtual body (but not a control object), and positively correlated with an increase in pain thresholds. We discuss the functional mechanisms of self-identification, self-location, and the visual perception of human bodies with respect to pain perception.

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