HypnoVR, Strasbourg, France.
Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, University of Strasbourg, Strasbourg, France.
J Med Internet Res. 2022 Jul 29;24(7):e33255. doi: 10.2196/33255.
Virtual reality hypnosis (VRH) is a promising tool to reduce pain. However, the benefits of VRH on pain perception and on the physiological expression of pain require further investigation.
In this study, we characterized the effects of VRH on the heat pain threshold among adult healthy volunteers while monitoring several physiological and autonomic functions.
Sixty healthy volunteers were prospectively included to receive nociceptive stimulations. The first set of thermal stimuli consisted of 20 stimulations at 60°C (duration 500 milliseconds) to trigger contact heat evoked potentials (CHEPs). The second set of thermal stimuli consisted of ramps (1°C/second) to determine the heat pain threshold of the participants. Electrocardiogram, skin conductance responses, respiration rate, as well as the analgesia nociception index were also recorded throughout the experiment.
Data from 58 participants were analyzed. There was a small but significant increase in pain threshold in VRH (50.19°C, SD 1.98°C) compared to that in the control condition (mean 49.45°C, SD 1.87; P<.001, Wilcoxon matched-pairs signed-rank test; Cohen d=0.38). No significant effect of VRH on CHEPs and heart rate variability parameters was observed (all P>0.5; n=22 and n=52, respectively). During VRH, participants exhibited a clear reduction in their autonomic sympathetic tone, as shown by the lower number of nonspecific skin conductance peak responses (P<.001, two-way analysis of variance; n=39) and by an increase in the analgesia nociception index (P<.001, paired t-test; n=40).
The results obtained in this study support the idea that VRH administration is effective at increasing heat pain thresholds and impacts autonomic functions among healthy volunteers. As a nonpharmacological intervention, VRH has beneficial action on acute experimental heat pain. This beneficial action will need to be evaluated for the treatment of other types of pain, including chronic pain.
虚拟现实催眠（VRH）是一种很有前途的减轻疼痛的工具。然而，VRH 对疼痛感知和疼痛的生理表现的益处需要进一步研究。
本研究旨在通过监测多种生理和自主功能，描述 VRH 对成年健康志愿者热痛阈的影响。
前瞻性纳入 60 名健康志愿者接受伤害性刺激。第一组热刺激由 20 次 60°C 的刺激组成（持续时间 500 毫秒），以引发接触热诱发电位（CHEPs）。第二组热刺激由斜坡（1°C/秒）组成，以确定参与者的热痛阈。在整个实验过程中，还记录了心电图、皮肤电反应、呼吸频率以及镇痛痛觉指数。
分析了 58 名参与者的数据。与对照条件相比，VRH 时的疼痛阈值略有显著升高（50.19°C，SD 1.98°C）（平均 49.45°C，SD 1.87；P<.001，Wilcoxon 配对符号秩检验；Cohen d=0.38）。VRH 对 CHEPs 和心率变异性参数无显著影响（均 P>0.5；n=22 和 n=52）。在 VRH 期间，参与者表现出自主交感神经张力明显降低，具体表现为非特异性皮肤电反应峰的数量减少（P<.001，双向方差分析；n=39）和镇痛痛觉指数增加（P<.001，配对 t 检验；n=40）。
本研究结果支持 VRH 给药可有效提高热痛阈并影响健康志愿者自主功能的观点。作为一种非药物干预措施，VRH 对急性实验性热痛具有有益作用。这种有益作用需要进一步评估其对其他类型疼痛（包括慢性疼痛）的治疗效果。
