经皮神经电刺激镇痛的脑电波功率谱研究

The modulatory effect of transcutaneous electrical nerve stimulation （TENS） on tonic heat pain in the human brain：topographic mapping of absolute EEG power spectra

目的研究经皮神经电刺激（TENS）对静息闭眼状态和疼痛状态脑电波的调制作用。方法采用128导高密度脑电记录仪记录15名健康男性大学生在静息闭眼、热痛刺激、TENS刺激和TENS调制对侧疼痛4个条件下的脑电波活动。用简易麦-吉评分量表来测量被试的主观疼痛感受，采用快速傅立叶转换（FFT）进行脑电波功率谱分析。结果@TENS刺激和静息闭眼状态：TENS显著地增强了头皮表面额部区域的Beta-1的活动，脑电波频谱值从静息状态（290±201）μV2增加到TENS刺激时的（385±224）μV2（t=3．323，P〈0．01）。（2）TENS调制和疼痛刺激：TENS显著的降低了被试在简易麦-吉量表里视觉评分（t=2．26，P〈0．05）和现有疼痛指数的评分（t=2．12，P〈0．05）。在疼痛诱发的脑电波背景下，TENS调制显著的增加了枕部和顶部Alpha-1的活动[疼痛时脑电波频谱值为（332±221）μV2，TENS调制时为（378±243）μV2，t=-3．683，P〈0．01]，同时增强了额部和枕部Beta-1的活动[疼痛时脑电波频谱值为（348±213）μV2，TENS调制时为（397±240）μV2，t-2．362，P〈0．05]。结论TENS作为一种外周感觉刺激，主要激活了感觉运动皮层的活动，TENS对侧调制疼痛时Alpha-1波段能量的增高反应了TENS可能使大脑对外界伤害性刺激的反应降低，缓解了被试对疼痛的情绪反应。

Objective To investigate the effect of transcutaneous electrical nerve stimulation （TENS） on baseline eyes-closed brain activation and on pain-related EEG activity when TENS is applied contralatarally to the hancl of pain. Method 128-channel electroencephalography （EEG） was recorded in four conditions including baseline,heat pain test, TENS stimulation and eontralateral TENS modulation in 15 right-handed healthy young males. The Short Form MeGill Pain Questionnaire was employed to assess pain sensation. Fast Fourier Transforma- tion analysis （FFT） was performed to calculate absolute EEG power spectra based on 7 bands spectrum. Results （1） The fronto-eentral beta-1 activity was significantly enhanced by TENS compared to eyes-closed [ eyes-dosed ： （290 ± 201 ）μV2, TENS ： （ 385 ± 224 ）μV2, t = 3. 323, P 〈 0.01 ]. （2）TENS markedly relived pain sensation assessed by SF-MPQ and significantly increased the posterior-anterior alpha-1 power [ pain：（332 ± 221 ）μV2 ,TENS modulation ： （378 ± 243 ） μV2, t = 3. 683, P 〈 0.01 ] and ffonto-eentral and posterior beta-1 activities [ pain ： （ 348 ±213μV2,TENS modulation：（397 ±240）μV2, t=2.362, P〈0.05]. Conclusion TENS,used as a peripheral nerve stimulation, mainly activates sensorimotor cortex. The increased Alpha-1 activity implies that TENS is like- ly able to relieve pain affeetive.