Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, 300192, China.
Neuroscience Center, Chinese Academy of Medical Sciences, Beijing, 100730, China.
Exp Brain Res. 2019 Oct;237(10):2735-2746. doi: 10.1007/s00221-019-05621-z. Epub 2019 Aug 21.
Repetitive transcranial magnetic stimulation combined with motor training (rTMS-MT) can be an effective method for enhancing motor function. However, the effects of rTMS-MT on inter-hemispheric lateralization remain unclear. Nineteen healthy volunteers were recruited. The volunteers were randomized to receive 2 weeks of rTMS-MT or MT to improve the motor function of the nondominant hand. Hand dexterity was tested by the Nine-Hole Peg Test. Resting motor threshold (RMT), motor evoked potentials (MEP) and electroencephalography (EEG) in the resting state with eyes closed were recorded, to calculate inter-hemispheric lateralization before and after rTMS-MT or MT. rTMS-MT and MT improved the dexterity and MEP amplitude of the nondominant hand. Furthermore, there were significant changes in the lateralization of not only power spectral density, but also information transmission efficiency between regions following rTMS-MT, especially between the central cortices of both hemispheres. However, although the lateralization change of the power spectral density between the central cortices was observed following MT, there was no such change for information transmission efficiency between any cortices. These results suggested that rTMS-MT could modulate inter-hemispheric lateralization. Changes in inter-hemispheric lateralization might be an important neural mechanism by which rTMS-MT improves motor function. These results could be helpful for understanding the brain mechanism of rTMS-MT.
重复经颅磁刺激联合运动训练（rTMS-MT）可有效增强运动功能。然而，rTMS-MT 对大脑两半球间侧化的影响尚不清楚。本研究纳入 19 名健康志愿者，随机分为 rTMS-MT 组和运动训练（MT）组，分别接受 2 周的 rTMS-MT 或 MT 以改善非优势手的运动功能。采用九孔插板测试评估手的灵巧度。在静息闭目状态下记录静息运动阈值（RMT）、运动诱发电位（MEP）和脑电图（EEG），以计算 rTMS-MT 或 MT 前后大脑两半球间的侧化。rTMS-MT 和 MT 均能提高非优势手的灵巧度和 MEP 振幅，rTMS-MT 后不仅功率谱密度，而且脑区间信息传递效率的侧化均发生显著变化，尤其是双侧中央皮质之间。而 MT 后仅观察到中央皮质间功率谱密度的侧化改变，但各皮质间信息传递效率无此改变。这些结果提示 rTMS-MT 可调节大脑两半球间的侧化。大脑两半球间侧化的改变可能是 rTMS-MT 改善运动功能的重要神经机制。这些结果有助于理解 rTMS-MT 的脑机制。
