Visuo-tactile stimulation, but not type of movement, modulates pain during the vision of a moving virtual limb.

Evidence has revealed a relationship between pain and the observation of limb movement, but it is unknown whether different types of movements have diverse modulating effects. In this immersive virtual reality study, we explored the effect of the vision of different virtual arm movements (arm vs wrist) on heat pain threshold of healthy participants. 40 healthy participants underwent four conditions in virtual reality, while heat pain thresholds were measured. Visuo-tactile stimulation was used to attempt to modulate the feeling of virtual limb ownership while the participants kept their arms still. Effects on pain threshold were present for type of stimulation but not type of movement. The type of observed movement does not appear to influence pain modulation, at least not during acute pain states.