Wang Jue, Deng Xin-Ping, Wu Yun-Ying, Li Xiao-Long, Feng Zi-Jian, Wang Hong-Xiao, Jing Ying, Zhao Na, Zang Yu-Feng, Zhang Jian
School of Psychology, Shanghai University of Sport, Shanghai, China.
Institute of Psychological Sciences, Hangzhou Normal University, Hangzhou, China.
Front Neurosci. 2020 Mar 19;14:186. doi: 10.3389/fnins.2020.00186. eCollection 2020.
Functional magnetic resonance imaging (fMRI) studies have shown that the effect of repetitive transcranial magnetic stimulation (rTMS) can induce changes in remote brain regions. In the stimulated regions, low-frequency (≤1 Hz) rTMS induces inhibitory effects, while high-frequency (≥5 Hz) stimulation induces excitatory effects. However, these stereotypical effects arising from low- and high-frequency stimulation are based on measurements of motor evoked potentials (MEPs) induced by pulsed stimulation. To test the effects of rTMS on remote brain regions, the current study recruited 31 young healthy adults who participated in three rTMS sessions (10 Hz high frequency, 1 Hz low frequency, and sham) on three separate days. The stimulation target was based on individual fMRI activation in the motor cortex evoked by a finger movement task. Pre- and post-rTMS resting-state fMRI (RS-fMRI) were acquired. Regional homogeneity (ReHo) and degree centrality (DC) were calculated to measure the local and global connectivity, respectively. Compared with the sham session, high-frequency (10 Hz) rTMS significantly increased ReHo and DC in the right cerebellum, while low-frequency (1 Hz) stimulation did not significantly alter ReHo or DC. Then, using a newly developed PAIR support vector machine (SVM) method, we achieved accuracy of 93.18-97.24% by split-half validation for pairwise comparisons between conditions for ReHo or DC. While the univariate analyses suggest that high-frequency rTMS of the left motor cortex could affect distant brain activity in the right cerebellum, the multivariate SVM results suggest that both high- and low-frequency rTMS significantly modulated widespread brain activity. The current findings are useful for increasing the understanding of the mechanisms of rTMS, as well as guiding precise individualized rTMS treatment of movement disorders.
功能磁共振成像（fMRI）研究表明，重复经颅磁刺激（rTMS）的效应可诱导远隔脑区发生变化。在受刺激区域，低频（≤1Hz）rTMS诱导抑制性效应，而高频（≥5Hz）刺激诱导兴奋性效应。然而，这些由低频和高频刺激产生的刻板效应是基于脉冲刺激诱发的运动诱发电位（MEP）测量得出的。为了测试rTMS对远隔脑区的影响，本研究招募了31名年轻健康成年人，他们在三个不同的日子参加了三次rTMS治疗（10Hz高频、1Hz低频和假刺激）。刺激靶点基于手指运动任务诱发的运动皮层中个体的fMRI激活情况。在rTMS治疗前后采集静息态fMRI（RS-fMRI）。分别计算局部一致性（ReHo）和度中心性（DC）以测量局部和全局连通性。与假刺激治疗相比，高频（10Hz）rTMS显著增加了右侧小脑的ReHo和DC，而低频（1Hz）刺激并未显著改变ReHo或DC。然后，使用新开发的配对支持向量机（SVM）方法，通过对ReHo或DC条件之间的配对比较进行折半验证，我们实现了93.18 - 97.24%的准确率。虽然单变量分析表明左侧运动皮层的高频rTMS可影响右侧小脑的远隔脑区活动，但多变量SVM结果表明高频和低频rTMS均显著调节广泛的脑区活动。当前的研究结果有助于增进对rTMS机制的理解，以及指导对运动障碍进行精确的个体化rTMS治疗。
