CAS Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
Department of Psychology, University of Chinese Academy of Sciences, Beijing, China.
Brain Struct Funct. 2021 Jan;226(1):151-162. doi: 10.1007/s00429-020-02173-9. Epub 2020 Nov 24.
Although the analgesic effects of conventional transcutaneous electrical nerve stimulation (TENS) and acupuncture-like TENS are evident, their respective neural mechanisms in humans remain controversial. To elucidate and compare the supraspinal neural mechanisms of the analgesic effects produced by conventional TENS (high frequency and low intensity) and acupuncture-like TENS (low frequency and high intensity), we employed a between-subject sham-controlled experimental design with conventional, acupuncture-like, and sham TENS in 60 healthy human volunteers. In addition to assessing the TENS-induced changes of subjective ratings of perceived pain, we examined the TENS associated brainstem activities (fractional amplitude of low frequency fluctuations, fALFF) and their corresponding resting state functional connectivity (RSFC) with higher-order brain areas using functional magnetic resonance imaging. The analgesic effect of conventional TENS was only detected in the forearm that received TENS, coupled with decreased pons activity and RSFC between pons and contralateral primary somatosensory cortex. In contrast, acupuncture-like TENS produced a spatially diffuse analgesic effect, coupled with increased activities in both subnucleus reticularis dorsalis (SRD) and rostral ventromedial medulla (RVM), and decreased RSFC between SRD and medial frontal regions as well as between SRD and lingual gyrus. To sum up, our data demonstrated that conventional TENS and acupuncture-like TENS have different analgesic effects, which are mediated by different supraspinal neural mechanisms.
尽管传统经皮电神经刺激（TENS）和类似针刺的 TENS 的镇痛效果明显，但它们在人类中的各自神经机制仍存在争议。为了阐明和比较传统 TENS（高频低强度）和类似针刺的 TENS（低频高强度）产生的镇痛作用的脊髓上神经机制，我们采用了一项在 60 名健康志愿者中进行的、基于受试者的假刺激对照实验设计，分别使用了传统 TENS、类似针刺的 TENS 和假刺激 TENS。除了评估 TENS 引起的感知疼痛的主观评分变化外，我们还使用功能磁共振成像检查了 TENS 相关的脑干活动（低频波动的分数幅度，fALFF）及其与高级脑区的对应静息状态功能连接（RSFC）。只有在接受 TENS 的前臂中才能检测到传统 TENS 的镇痛效果，同时伴随着脑桥活动的减少和脑桥与对侧初级体感皮层之间的 RSFC 减少。相比之下，类似针刺的 TENS 产生了空间弥散的镇痛效果，伴随着背侧网状核（SRD）和腹内侧前脑髓质（RVM）活动的增加，以及 SRD 与内侧额区之间以及 SRD 与舌回之间的 RSFC 减少。总之，我们的数据表明，传统 TENS 和类似针刺的 TENS 具有不同的镇痛效果，这些效果是由不同的脊髓上神经机制介导的。
