A limited set of muscle synergies for force control during a postural task
A limited set of muscle synergies for force control during a postural task
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DOI：
10.1152/jn.00681.2004
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发表时间：
2005-01-01
影响因子：
2.5
通讯作者：
Macpherson, JM
中科院分区：
文献类型：
--
作者：
Ting, LH;Macpherson, JM
最近开发的计算技术已被用来减少肌肉激活模式的高度复杂性，以一个简单的协同组织，并带来新的见解，长期存在的自由度的问题，在电机控制。我们使用了非负因子分解的方法，以确定在猫的姿势反应的肌肉协同作用，并检查这种协同作用的自然行为的功能意义。我们假设，肌肉协同作用所提供的神经控制的简化必须与生物力学水平上的自由度的类似减少相匹配。从暴露于16个方向的支撑表面平移的猫的8-15条后肢肌肉记录肌电图数据。结果表明，四种协同作用可以解释所有肌肉和所有方向的自动姿势反应的95%以上。每一个协同作用被激活的一组特定的扰动方向，而且，每个都与一个独特的向量的端点下的肢体的力量。我们认为，在主动平衡控制的背景下，姿势的协同作用反映了神经命令信号，指定端点的肢体力量。
Recently developed computational techniques have been used to reduce muscle activation patterns of high complexity to a simple synergy organization and to bring new insights to the long-standing degrees of freedom problem in motor control. We used a nonnegative factorization approach to identify muscle synergies during postural responses in the cat and to examine the functional significance of such synergies for natural behaviors. We hypothesized that the simplification of neural control afforded by muscle synergies must be matched by a similar reduction in degrees of freedom at the biomechanical level. Electromyographic data were recorded from 8-15 hindlimb muscles of cats exposed to 16 directions of support surface translation. Results showed that as few as four synergies could account for >95% of the automatic postural response across all muscles and all directions. Each synergy was activated for a specific set of perturbation directions, and moreover, each was correlated with a unique vector of endpoint force under the limb. We suggest that, within the context of active balance control, postural synergies reflect a neural command signal that specifies endpoint force of a limb.