Pozeg Polona, Palluel Estelle, Ronchi Roberta, Solcà Marco, Al-Khodairy Abdul-Wahab, Jordan Xavier, Kassouha Ammar, Blanke Olaf
From the Laboratory of Cognitive Neuroscience, Brain Mind Institute (P.P., R.R., M.S., O.B.), and Center for Neuroprosthetics (P.P., E.P., R.R., M.S., O.B.), School of Life Sciences, École Polytechnique Fédérale de Lausanne, Campus Biotech, Geneva, Switzerland; University Grenoble Alpes & CNRS (E.P.), TIMC-IMAG, Grenoble, France; Spinal Cord Unit (A.-W.A.-K., X.J.), Clinique Romande de Réadaptation SUVACare, Sion; and Division of Neurorehabilitation, Department of Clinical Neuroscience (A.K.), and Department of Neurology (O.B.), University Hospital of Geneva, Switzerland.
Neurology. 2017 Oct 31;89(18):1894-1903. doi: 10.1212/WNL.0000000000004585. Epub 2017 Oct 6.
To investigate changes in body ownership and chronic neuropathic pain in patients with spinal cord injury (SCI) using multisensory own body illusions and virtual reality (VR).
Twenty patients with SCI with paraplegia and 20 healthy control participants (HC) participated in 2 factorial, randomized, repeated-measures design studies. In the virtual leg illusion (VLI), we applied asynchronous or synchronous visuotactile stimulation to the participant's back (either immediately above the lesion level or at the shoulder) and to the virtual legs as seen on a VR head-mounted display. We tested the effect of the VLI on the sense of leg ownership (questionnaires) and on perceived neuropathic pain (visual analogue scale pain ratings). We compared illusory leg ownership with illusory global body ownership (induced in the full body illusion [FBI]), by applying asynchronous or synchronous visuotactile stimulation to the participant's back and the back of a virtual body as seen on a head-mounted display.
Our data show that patients with SCI are less sensitive to multisensory stimulations inducing illusory leg ownership (as compared to HC) and that leg ownership decreased with time since SCI. In contrast, we found no differences between groups in global body ownership as tested in the FBI. VLI and FBI were both associated with mild analgesia that was only during the VLI specific for synchronous visuotactile stimulation and the lower back position.
The present findings show that VR exposure using multisensory stimulation differently affected leg vs body ownership, and is associated with mild analgesia with potential for SCI neurorehabilitation protocols.
使用多感官自我身体错觉和虚拟现实（VR）研究脊髓损伤（SCI）患者的身体所有权变化和慢性神经性疼痛。
20例患有截瘫的SCI患者和20名健康对照参与者（HC）参与了2项析因、随机、重复测量设计研究。在虚拟腿部错觉（VLI）中，我们对参与者的背部（病变水平上方或肩部）以及VR头戴式显示器上看到的虚拟腿部施加异步或同步视觉触觉刺激。我们测试了VLI对腿部所有权感（问卷）和感知神经性疼痛（视觉模拟量表疼痛评分）的影响。通过对参与者的背部和头戴式显示器上看到的虚拟身体背部施加异步或同步视觉触觉刺激，我们将虚幻的腿部所有权与虚幻的整体身体所有权（在全身错觉[FBI]中诱发）进行了比较。
我们的数据表明，SCI患者对诱导虚幻腿部所有权的多感官刺激的敏感性低于HC，并且腿部所有权随SCI后的时间而降低。相比之下，我们发现在FBI测试中，两组在整体身体所有权方面没有差异。VLI和FBI均与轻度镇痛相关，且仅在VLI期间，对于同步视觉触觉刺激和下背部位置具有特异性。
目前的研究结果表明，使用多感官刺激的VR暴露对腿部与身体所有权的影响不同，并且与轻度镇痛相关，具有用于SCI神经康复方案的潜力。
