Qi Xingang, Jia Tianzhe, Sun Baijintao, Xia Jiahui, Wang ChenXi, Hong Zilong, Zhang Yi, Yang Hanfeng, Zhang Chuan, Liu Jixin
Department of Radiology, Affiliated Hospital of North Sichuan Medical College, Sichuan 637000, PR China; Center for Brain Imaging, School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi 710126, PR China; International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment & Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710126, PR China.
Center for Brain Imaging, School of Life Science and Technology, Xidian University & Engineering Research Center of Molecular and Neuro Imaging, Ministry of Education, Xi'an, Shaanxi 710126, PR China; International Joint Research Center for Advanced Medical Imaging and Intelligent Diagnosis and Treatment & Xi'an Key Laboratory of Intelligent Sensing and Regulation of trans-Scale Life Information, School of Life Science and Technology, Xidian University, Xi'an, Shaanxi 710126, PR China.
Neuroimage. 2025 May 15;312:121237. doi: 10.1016/j.neuroimage.2025.121237. Epub 2025 Apr 23.
High-definition transcranial alternating current stimulation (HD-tACS) targeting alpha rhythms (8-13 Hz) shows promise as a pain-relieving intervention, but individual responses vary widely. Understanding the neurobiological mechanism behind this variability is crucial for optimizing HD-tACS parameters to enhance its efficacy in pain relief. In a double-blind, within-subject, sham-controlled experimental study, 34 healthy participants were recruited. We investigated how individual differences in brain oscillations during rest and capsaicin-induced sustained pain states influence the efficacy of alpha HD-tACS. Participants underwent EEG assessments at rest and during capsaicin-induced sustained pain. They then received either sham or active HD-tACS on the sensorimotor cortex (SM1) or dorsolateral prefrontal cortex (DLPFC). We found significant reductions in delta and theta band power at the C4 electrode during sustained pain correlated with individual pain intensity. Additionally, stimulating the SM1 and DLPFC significantly relieved sustained pain. Resting alpha band power and changes in theta band power during sustained pain (the difference in theta band power between sustained pain and rest) at the C4 electrode were both significantly correlated with the pain-relieving efficacy of alpha HD-tACS on SM1. Notably, changes in theta band power mediated the relationship between resting alpha band power and pain-relieving efficacy. These results were not found with alpha HD-tACS on DLPFC. Our results suggest that the variations in theta band power during sustained pain may be crucial for understanding the variability in the efficacy of alpha HD-tACS targeting SM1. The factors influencing the efficacy of alpha HD-tACS on the DLPFC might be multifaceted.
针对阿尔法节律（8 - 13赫兹）的高清晰度经颅交流电刺激（HD - tACS）显示出作为一种止痛干预措施的前景，但个体反应差异很大。了解这种变异性背后的神经生物学机制对于优化HD - tACS参数以提高其止痛效果至关重要。在一项双盲、受试者内、假对照实验研究中，招募了34名健康参与者。我们研究了静息状态和辣椒素诱导的持续性疼痛状态下脑振荡的个体差异如何影响阿尔法HD - tACS的疗效。参与者在静息状态和辣椒素诱导的持续性疼痛期间接受脑电图评估。然后他们在感觉运动皮层（SM1）或背外侧前额叶皮层（DLPFC）接受假刺激或主动HD - tACS。我们发现，持续性疼痛期间C4电极处的δ波和θ波功率显著降低与个体疼痛强度相关。此外，刺激SM1和DLPFC可显著缓解持续性疼痛。静息阿尔法波功率以及持续性疼痛期间C4电极处θ波功率的变化（持续性疼痛和静息状态下θ波功率的差异）均与阿尔法HD - tACS对SM1的止痛效果显著相关。值得注意的是，θ波功率的变化介导了静息阿尔法波功率与止痛效果之间的关系。在DLPFC上进行阿尔法HD - tACS时未发现这些结果。我们的结果表明，持续性疼痛期间θ波功率的变化可能对于理解针对SM1的阿尔法HD - tACS疗效的变异性至关重要。影响阿尔法HD - tACS对DLPFC疗效的因素可能是多方面的。
