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Abstract

Background: The rubber hand illusion (RHI) is an experimental paradigm which manipulates the sense of body ownership mediated by multisensory perceptual correlations. Synchronous brushing of a visible rubber hand and the person’s own hand produces a feeling of body ownership for the rubber hand while inducing disembodiment, a disruption of body ownership, in the real hand. Previous research has demonstrated that disembodiment induces cooling of the disembodied body part as well as desensitization to tactile stimuli. Objectives: We wanted to investigate whether disembodiment of a body part induced by the RHI affects the perception of penetration and pain induced by an acupuncture needle, and which individual factors are related to it. Methods: Participants had to fill out questionnaires such as the perception of bodily senses (PBS), fear of pain (FPQ), and beck’s anxiety index (BAI) questionnaire. We elicited RHI using the standard experimental protocol and applied acupuncture needle stimulation to the real hand while measuring concurrent psychophysiological changes such as skin conductance rate (SCR). Subjective responses such as the perception of the RHI, needle penetration and pain were also collected. Results: RHI was successfully induced in most of the participants. Psychophysiological markers did not reveal a significant difference in pain and penetration perception of acupuncture needle stimuli depending on the induction of rubber hand illusion. However, visual expectation of needle stimulation seemed to influence the patterns of responses, as well as differences in individual traits seemed to matter in different tendencies of responses. Conclusions: Psychophysiological changes do not seem to predict differential responses to acupuncture stimulation during modification of body ownerships, but visually induced expectations seem to influence the patterns of psychophysiological responses as well as the perception of penetration and pain to acupuncture needle stimulation.