Hand movement in humans is verified as asymmetries and lateralization, and two hemispheres make some distinct but complementary contributions in the control of hand movement. However, little research has been done on whether the information transfer of the motor system is different between left and right hand movement. Considering the importance of functional corticomuscular coupling (FCMC) between the motor cortex and contralateral muscle in movement assessment, this study aimed to explore the differences between left and right hand by investigating the interaction between muscle and brain activity. Here, we applied the transfer spectral entropy (TSE) algorithm to quantize the connection between electroencephalogram (EEG) over the brain scalp and electromyogram (EMG) from extensor digitorum (ED) and flexor digitorum superficialis (FDS) muscles recorded simultaneously during a gripping task. Eight healthy subjects were enrolled in this study. Results showed that left hand yielded narrower and lower beta synchronization compared to the right. Further analysis indicated coupling strength in EEG-EMG(FDS) combination was higher at beta band than that in EEG-EMG(ED) combination, and exhibited distinct differences between descending (EEG to EMG direction) and ascending (EMG to EEG direction) direction. This study presents the distinctions of beta-range FCMC between left and right hand, and confirms the importance of beta synchronization in understanding the mechanism of motor stability control. The cortex-muscle FCMC might be used as an evaluation approach to explore the difference between left and right movement system.

中文翻译：

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β范围的皮质束耦合反映手运动中的不对称性。

事实证明，人类的手部运动具有不对称性和侧向性，并且两个半球在控制手部运动方面做出了一些独特但互补的贡献。但是，关于左手和右手运动之间电机系统的信息传递是否不同的研究很少。考虑到运动皮层和对侧肌肉之间功能性皮层肌肉耦合（FCMC）在运动评估中的重要性，本研究旨在通过研究肌肉与大脑活动之间的相互作用来探索左右手之间的差异。这里，我们应用了传递光谱熵（TSE）算法来量化在抓紧任务期间同时记录的头皮上的脑电图（EEG）与伸指（ED）和指浅屈肌（FDS）肌肉的肌电图（EMG）之间的关系。八名健康受试者参加了这项研究。结果显示，与右手相比，左手产生更窄和更低的beta同步。进一步的分析表明，EEG-EMG（FDS）组合在β波段的耦合强度高于EEG-EMG（ED）组合，并且在下降（EEG到EMG方向）和上升（EMG到EEG方向）之间表现出明显的差异。 。这项研究提出了左手和右手之间β范围FCMC的区别，并确认了Beta同步对理解电机稳定性控制机制的重要性。皮质肌肉FCMC可以用作评估左右运动系统之间差异的评估方法。