Yaw Postural Perturbation Through Robotic Platform: Aging Effects on Muscle Synergies
Yaw Postural Perturbation Through Robotic Platform: Aging Effects on Muscle Synergies
复制标题
通过机器人平台的偏航姿势扰动：衰老对肌肉协同作用的影响
DOI：
10.1109/biorob.2018.8488085
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
E. Palermo
中科院分区：
文献类型：
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作者：
Juri Taborri;Ilaria Mileti;Z. Prete;S. Rossi;E. Palermo
衰老导致肌肉系统恶化，这可能导致平衡障碍，增加福尔斯的风险。该研究旨在评估老化对肌肉激活的影响，以响应RotoBiT 1D施加的偏航旋转。八名年轻人和八名老年人参加了这项研究。通过RotoBiT 1D平台在两种速度条件下对受试者施加围绕偏航轴的55°右S形旋转，其特征在于角速度峰值分别等于80¼/s和100 °/s。采用无线表面肌电图仪记录双侧上肢16块肌肉的电活动。进行非负矩阵分解以提取肌肉协同作用。肌肉协同作用的数量是通过使用变异性帐户来选择的。计算相似性余弦，以量化与肌肉协同向量相关的组内和组间相似性。肌肉协同作用的数量在年轻人中为4至6个，在老年人中为3至6个，尽管在组间或速度条件下没有发现统计学差异。至于组内相似性，年轻的成年人显示值总是高于相似性阈值，而在老年人中观察到较低的相似性，证实了姿势反应的异质性。肌肉协同向量的整体结构在组间并不相似，组间的相似性随着速度的增加而降低。在涉及头部和上肢肌肉的协同作用方面，差异更大。研究结果揭示了不同的肌肉协同组织的肌肉协同矢量。这样一个不同的组织要求更深入的调查，以确定老年人跌倒的原因。
Aging causes a worsening in muscle system, which could cause balance impairments, increasing the risk of falls. The study aims at evaluating the effects of aging on muscle activation in response to a yaw rotation imposed by the RotoBiT1D. Eight younger and eight older adults were enrolled in the study. A right sigmoidal rotation of 55° around the yaw axis was imposed to the subject by means of the RotoBiT1D platform in two velocity conditions, characterized by an angular velocity peak equal to 80¼/s and 100 °/s, respectively. The activations of 16 bilateral muscles of upper body were recorded through wireless surface electromyography. A Non-Negative Matrix Factorization was performed to extract the muscle synergies. The number of muscle synergies was selected by using the Variability Account For. The cosine of similarity was computed for the quantification of intra-group and inter-group similarity related to the muscle synergy vectors. The number of muscle synergies ranged from 4 to 6 in younger and from 3 to 6 in older, even though no statistical difference was found between groups or velocity conditions. As regards intra-group similarity, younger adults showed values always above the similarity threshold; while a lower similarity was observed in older adults, confirming the heterogeneity of postural response. The overall structure of muscle synergy vectors was not similar between groups and the inter-group similarity decreased with the increase of the velocity. The differences were greater in synergies involving head and upper limb muscles. Findings unveiled a different muscle synergy organization in terms of muscle synergy vectors. Such a different organization calls for a deeper investigation towards the aim of identifying causes of fall in elderly.