Osaka University, Institute for Advanced Co-Creation Studies, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Osaka University Graduate School of Medicine, Department of Neurosurgery, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; ATR Computational Neuroscience Laboratories, Department of Neuroinformatics, 2-2-2 Hikaridai, Seika-cho, Kyoto 619-0288, Japan.
Osaka University, Institute for Advanced Co-Creation Studies, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; Osaka University Graduate School of Medicine, Department of Neurosurgery, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan; ATR Computational Neuroscience Laboratories, Department of Neuroinformatics, 2-2-2 Hikaridai, Seika-cho, Kyoto 619-0288, Japan.
J Pain. 2022 Dec;23(12):2080-2091. doi: 10.1016/j.jpain.2022.07.009. Epub 2022 Aug 3.
Phantom limb pain is attributed to abnormal sensorimotor cortical representations, although the causal relationship between phantom limb pain and sensorimotor cortical representations suffers from the potentially confounding effects of phantom hand movements. We developed neurofeedback training to change sensorimotor cortical representations without explicit phantom hand movements or hand-like visual feedback. We tested the feasibility of neurofeedback training in fourteen patients with phantom limb pain. Neurofeedback training was performed in a single-blind, randomized, crossover trial using two decoders constructed using motor cortical currents measured during phantom hand movements; the motor cortical currents contralateral or ipsilateral to the phantom hand (contralateral and ipsilateral training) were estimated from magnetoencephalograms. Patients were instructed to control the size of a disk, which was proportional to the decoding results, but to not move their phantom hands or other body parts. The pain assessed by the visual analogue scale was significantly greater after contralateral training than after ipsilateral training. Classification accuracy of phantom hand movements significantly increased only after contralateral training. These results suggested that the proposed neurofeedback training changed phantom hand representation and modulated pain without explicit phantom hand movements or hand-like visual feedback, thus showing the relation between the phantom hand representations and pain. PERSPECTIVE: Our work demonstrates the feasibility of using neurofeedback training to change phantom hand representation and modulate pain perception without explicit phantom hand movements and hand-like visual feedback. The results enhance the mechanistic understanding of certain treatments, such as mirror therapy, that change the sensorimotor cortical representation.
幻肢痛归因于异常的感觉运动皮质代表，但幻肢痛与感觉运动皮质代表之间的因果关系受到幻手运动潜在混杂效应的影响。我们开发了神经反馈训练，以改变感觉运动皮质代表，而无需进行明确的幻手运动或类似手的视觉反馈。我们在 14 名幻肢痛患者中测试了神经反馈训练的可行性。神经反馈训练在一项单盲、随机、交叉试验中进行，使用两种解码器，这些解码器是使用在幻手运动期间测量的运动皮质电流构建的；对来自脑磁图的幻手对侧或同侧（对侧和同侧训练）的运动皮质电流进行估计。患者被指示控制一个磁盘的大小，该磁盘与解码结果成正比，但不要移动他们的幻手或其他身体部位。视觉模拟量表评估的疼痛在对侧训练后明显大于同侧训练后。仅在对侧训练后，幻手运动的分类准确性才显著提高。这些结果表明，所提出的神经反馈训练改变了幻手的代表，并调节了疼痛，而无需明确的幻手运动或类似手的视觉反馈，从而显示了幻手代表与疼痛之间的关系。观点：我们的工作证明了使用神经反馈训练来改变幻手代表和调节疼痛感知而无需明确的幻手运动和类似手的视觉反馈是可行的。这些结果增强了对某些治疗方法（如镜像疗法）的机制理解，这些治疗方法改变了感觉运动皮质代表。
