Matamala-Gomez Marta, Nierula Birgit, Donegan Tony, Slater Mel, Sanchez-Vives Maria V
Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona 08036, Spain.
Event-Lab, Department of Clinical Psychology and Psychobiology, Universitat de Barcelona, 08035 Barcelona, Spain.
J Clin Med. 2020 Jan 21;9(2):291. doi: 10.3390/jcm9020291.
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.
身体表征的变化可能会影响疼痛感知。诸如截肢患者的伸缩效应等身体形象扭曲对疼痛感知的影响尚不清楚。本研究旨在调查在虚拟现实中扭曲具身化虚拟手臂（模拟截肢者的伸缩效应）是否会调节健康参与者的疼痛感知和对疼痛的预期反应。27名右利手参与者沉浸在虚拟现实中，虚拟手臂以三种不同程度的扭曲呈现，同时有一个虚拟威胁刺激接近或接触虚拟手。我们在每种情况后评估疼痛/不适评分、所有权感和皮肤电导率反应（SCR）。与观看正常对照手臂相比，观看扭曲的虚拟手臂会增强对威胁事件的SCR，但当观看变红的扭曲虚拟手臂时，对威胁的SCR会相对降低。对扭曲和变红的扭曲虚拟手臂的所有权感水平与疼痛/不适水平之间存在正相关，但在正常对照手臂中不存在。与威胁刺激的接触显著增强SCR和疼痛/不适，而在模拟接触条件下SCR和疼痛/不适则降低。这些结果为身体形象与疼痛感知之间的双向联系提供了进一步的证据。
