Cheung Vincent C K, Zheng Xiao-Chang, Cheung Roy T H, Chan Rosa H M
1 School of Biomedical Sciences and Gerald Choa Neuroscience Centre, and the KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research of Common DiseasesThe Chinese University of Hong Kong Hong Kong China.
2 Department of Rehabilitation SciencesThe Hong Kong Polytechnic University Hong Kong China.
IEEE Open J Eng Med Biol. 2020 Feb 14;1:33-40. doi: 10.1109/OJEMB.2019.2963666. eCollection 2020.
Motor variability - performance variations across task repetitions - has been assumed to be undesirable. But recent studies argue that variability facilitates early motor learning by allowing exploratory search of reward-generating motion, and that variability's structure may be modulated by neural circuits for furthering learning. What are the neural sources of learning-relevant motor variability and its modulation in humans of different ages? Elderlies and young adults played a 3-session virtual bowling while multi-muscle electromyographic signals were collected. We quantified trial-to-trial variability of muscle synergies - neuromotor control modules - and of their activations. In elderlies, bowling-score gain correlated with change of activation timing variability of specific synergies, but in young adults, with variability changes of synergy-activation magnitude, and of the synergies themselves. Variability modulation of specific muscle synergies and their activations contribute to early motor learning. Elderly and young individuals may rely on different aspects of motor variability to drive learning.
运动变异性——任务重复过程中的表现变化——一直被认为是不理想的。但最近的研究认为，变异性通过允许对产生奖励的动作进行探索性搜索来促进早期运动学习，并且变异性的结构可能会被神经回路调节以进一步促进学习。在不同年龄段的人类中，与学习相关的运动变异性及其调节的神经来源是什么？老年人和年轻人进行了为期三阶段的虚拟保龄球游戏，同时收集多肌肉肌电信号。我们量化了肌肉协同作用（神经运动控制模块）及其激活的逐次试验变异性。在老年人中，保龄球得分的提高与特定协同作用的激活时间变异性的变化相关，但在年轻人中，与协同作用激活幅度和协同作用本身的变异性变化相关。特定肌肉协同作用及其激活的变异性调节有助于早期运动学习。老年人和年轻人可能依赖运动变异性的不同方面来驱动学习。
