title: The body fades away: investigating the effects of transparency of an embodied virtual body on pain threshold and body ownership.
abstract: The feeling of "ownership" over an external dummy/virtual body (or body part) has been proven to have both physiological and behavioural consequences. For instance, the vision of an "embodied" dummy or virtual body can modulate pain perception. However, the impact of partial or total invisibility of the body on physiology and behaviour has been hardly explored since it presents obvious difficulties in the real world. In this study we explored how body transparency affects both body ownership and pain threshold. By means of virtual reality, we presented healthy participants with a virtual co-located body with four different levels of transparency, while participants were tested for pain threshold by increasing ramps of heat stimulation. We found that the strength of the body ownership illusion decreases when the body gets more transparent. Nevertheless, in the conditions where the body was semi-transparent, higher levels of ownership over a see-through body resulted in an increased pain sensitivity. Virtual body ownership can be used for the development of pain management interventions. However, we demonstrate that providing invisibility of the body does not increase pain threshold. Therefore, body transparency is not a good strategy to decrease pain in clinical contexts, yet this remains to be tested.
authors.affiliation: Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Event-Lab, Facultat de Psicologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Matteo
authors.initials: M
authors.lastname: Martini
authors.affiliation: Event-Lab, Facultat de Psicologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Konstantina
authors.initials: K
authors.lastname: Kilteni
authors.affiliation: Event-Lab, Facultat de Psicologia, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Antonella
authors.initials: A
authors.lastname: Maselli
authors.affiliation: Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.|Event-Lab, Facultat de Psicologia, Universitat de Barcelona, Barcelona, Spain.|Institució Catalana Recerca i Estudis Avançats (ICREA), Barcelona, Spain.|Departamento de Psicología Básica, Universitat de Barcelona, Barcelona, Spain.
authors.forename: Maria V
authors.initials: MV
authors.lastname: Sanchez-Vives
mesh_terms: D001828:Body Image / Q000523:psychology*; D003198:Computer Simulation; D005260:Female; D006225:Hand / Q000502:physiology; D006358:Hot Temperature; D006801:Humans; D007088:Illusions / Q000502:physiology / Q000523:psychology*; D059225:Nociception / Q000502:physiology; D010067:Ownership; D010146:Pain / Q000503:physiopathology / Q000523:psychology*; D017288:Pain Threshold / Q000502:physiology / Q000523:psychology*; D055698:Touch Perception / Q000502:physiology; D014584:User-Computer Interface; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult