Highlights• Seeing your embodied virtual body in virtual reality increases pain threshold.• To increase pain threshold your virtual and real body should be co-located.• For the arm, this analgesic effect diminishes when there are 30 cm between virtual and real arm. AbstractSeeing one's own body has been reported to have analgesic properties. Analgesia has also been described when seeing an embodied virtual body co-located with the real one. However, there is a controversy regarding whether this effect holds true when seeing an illusory-owned body part, such as during the rubber-hand illusion. A critical difference between these paradigms is the distance between real and surrogate body part. Co-location of real arm and surrogate is possible in an immersive virtual environment, but not during illusory ownership of a rubber arm. The present study aimed at testing whether the distance between real and virtual arm can explain such differences in terms of pain modulation. Employing a paradigm of embodiment of a virtual body allowed us to evaluate heat pain thresholds (HPT) at co-location and at 30-cm distance between real and virtual arm. We observed significantly higher HPT at co-location than at 30-cm distance.The analgesic effects of seeing a virtual co-located arm are eliminated when increasing the distance between real and virtual arm which explains why seeing an illusorily owned rubber arm does not consistently result in analgesia. These findings are relevant for the use of virtual reality in pain management. PerspectiveLooking at a virtual body has analgesic properties similar to looking at one's real body. We identify the importance of co-location between real and surrogate body for this to occur and thereby respond to a scientific controversy. This information is useful for immersive virtual reality in pain management.Analgesia, body ownership, pain, rubber hand illusion, virtual environments. M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT were attached to the dorsal distal phalanges of their right index and middle fingers for the delivery of tactile stimuli. Noise isolation was ensured by administration of pink noise.Familiarization phase. Participants were first familiarized with the virtual body illusion: they donned the head-mounted display through which they saw a virtual male body located at the same place of their own body. When they looked down they saw this virtual body sitting on a P = 0.034); there was no significant interaction between synchrony of VTS and distance on MultipleHands (z = 1.19, n.s).

Changes in body representation may affect pain perception. The effect of a distorted body image, such as the telescoping effect in amputee patients, on pain perception, is unclear. This study aimed to investigate whether distorting an embodied virtual arm in virtual reality (simulating the telescoping effect in amputees) modulated pain perception and anticipatory responses to pain in healthy participants. Twenty-seven right-handed participants were immersed in virtual reality and the virtual arm was shown with three different levels of distortion with a virtual threatening stimulus either approaching or contacting the virtual hand. We evaluated pain/discomfort ratings, ownership, and skin conductance responses (SCRs) after each condition. Viewing a distorted virtual arm enhances the SCR to a threatening event with respect to viewing a normal control arm, but when viewing a reddened-distorted virtual arm, SCR was comparatively reduced in response to the threat. There was a positive relationship between the level of ownership over the distorted and reddened-distorted virtual arms with the level of pain/discomfort, but not in the normal control arm. Contact with the threatening stimulus significantly enhances SCR and pain/discomfort, while reduced SCR and pain/discomfort were seen in the simulated-contact condition. These results provide further evidence of a bi-directional link between body image and pain perception.