Similarity of Hand Muscle Synergies Elicited by Transcranial Magnetic Stimulation and Those Found During Voluntary Movement
Similarity of Hand Muscle Synergies Elicited by Transcranial Magnetic Stimulation and Those Found During Voluntary Movement
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经颅磁刺激引起的手部肌肉协同作用与自主运动期间发现的手部肌肉协同作用的相似性
DOI：
10.1152/jn.00537.2020
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发表时间：
2022
影响因子：
2.5
通讯作者：
Tunik, Eugene
中科院分区：
文献类型：
--
作者：
Yarossi, Mathew;Brooks, Dana H.;Erdoğmuş, Deniz;Tunik, Eugene
在人类和动物模型中的趋同证据表明，外源性刺激运动皮质(M1)在手中引起的反应具有类似于在自愿抓握运动中发现的模块结构。本研究的目的是建立肌肉对M1的经颅磁刺激(TMS)反应的模块化在多大程度上类似于涉及手指分割的自主性手部运动时肌肉激活的模块化。对8名健康人的8块手-前臂肌肉进行了肌电记录。使用非负矩阵因式分解来定义模块化，以识别在高密度TMS映射M1和美国手语字母表中的自愿手势形成期间记录的EMG数据的复杂激活模式的低等级近似(空间肌肉协同)。对协同作用的分析显示，来自经颅多发性硬化症的患者与来自自愿行动的患者之间的相似性大于偶然性。这两组数据都包括由单一固有手部肌肉主导的协同效应，估计是为了满足手指高度分割运动的需求。这些结果表明，在手势的形成过程中，皮质脊髓与个体固有肌肉的连接可能与通过协同作用而激活的模块化多肌相结合。这是第一次研究手部肌肉对运动皮质的经颅磁刺激(TMS)反应的模块化反应与来自手部随意运动的模块化反应的相似性。我们表明，TMS诱发的手部肌肉协同效应，在静止时测量，反映了在涉及手指分割的自愿行为中发现的那些。这项工作为进一步使用TMS研究人体运动系统中的肌肉激活模块提供了基础。
Converging evidence in human and animal models suggests that exogenous stimulation of the motor cortex (M1) elicits responses in the hand with similar modular structure to that found during voluntary grasping movements. The aim of this study was to establish the extent to which modularity in muscle responses to transcranial magnetic stimulation (TMS) to M1 resembles modularity in muscle activation during voluntary hand movements involving finger fractionation. Electromyography (EMG) was recorded from eight hand-forearm muscles in eight healthy individuals. Modularity was defined using non-negative matrix factorization to identify low-rank approximations (spatial muscle synergies) of the complex activation patterns of EMG data recorded during high-density TMS mapping of M1 and voluntary formation of gestures in the American Sign Language alphabet. Analysis of synergies revealed greater than chance similarity between those derived from TMS and those derived from voluntary movement. Both data sets included synergies dominated by single intrinsic hand muscles presumably to meet the demand for highly fractionated finger movement. These results suggest that corticospinal connectivity to individual intrinsic hand muscles may be combined with modular multimuscle activation via synergies in the formation of hand postures.NEW & NOTEWORTHYThis is the first work to examine the similarity of modularity in hand muscle responses to transcranial magnetic stimulation (TMS) of the motor cortex and that derived from voluntary hand movement. We show that TMS-elicited muscle synergies of the hand, measured at rest, reflect those found in voluntary behavior involving finger fractionation. This work provides a basis for future work using TMS to investigate muscle activation modularity in the human motor system.