Arm dominance affects feedforward strategy more than feedback sensitivity during a postural task
Arm dominance affects feedforward strategy more than feedback sensitivity during a postural task
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在姿势任务中，手臂优势对前馈策略的影响大于反馈灵敏度
DOI：
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发表时间：
2015
影响因子：
2
通讯作者：
E. Perreault
中科院分区：
文献类型：
--
作者：
Elise H. E. Walker;E. Perreault
惯用手是人类运动控制的一个特征，目前尚未完全了解。最近的研究表明，主导臂和非主导臂各自擅长不同的行为，并提出这种行为不对称源于大脑皮层的偏侧化：主导侧专门用于预测轨迹控制，而非主导侧专门用于阻抗控制。长潜伏期牵张反射是一种调节姿势的自动机制，并已被证明有助于肢体阻抗。为了确定长潜伏反射是否也会导致上肢的不对称运动行为，我们研究了在需要不同程度的阻抗控制的姿势任务期间手臂优势对牵张反射的影响。我们的结果表明，非优势手臂的双关节肌肉的反射反应略有但明显更大，这与增加的阻抗控制是一致的。这些差异仅归因于非优势双关节肌肉中较高水平的自愿背景活动，表明姿势稳定性的前馈策略可能在手臂之间有所不同。反射敏感性被定义为对匹配的背景活动水平的反射反应的强度，对于 23 岁至 51 岁的广泛受试者群体，各组之间没有显着差异。这些结果表明，在广泛的受试者群体中，前馈策略的臂间差异在姿势过程中比反馈敏感性的差异更具影响力。有趣的是，将我们的分析限制在 40 岁以下的受试者中，结果表明，相对于优势臂，非优势臂的长潜伏期反射敏感性略有增加。尽管我们的二次分析的受试者数量很少，但这表明可能需要进一步的研究来评估反射偏侧化在整个发育过程中的影响。
Handedness is a feature of human motor control that is still not fully understood. Recent work has demonstrated that the dominant and nondominant arm each excel at different behaviors and has proposed that this behavioral asymmetry arises from lateralization in the cerebral cortex: the dominant side specializes in predictive trajectory control, while the nondominant side is specialized for impedance control. Long-latency stretch reflexes are an automatic mechanism for regulating posture and have been shown to contribute to limb impedance. To determine whether long-latency reflexes also contribute to asymmetric motor behavior in the upper limbs, we investigated the effect of arm dominance on stretch reflexes during a postural task that required varying degrees of impedance control. Our results demonstrated slightly but significantly larger reflex responses in the biarticular muscles of the nondominant arm, as would be consistent with increased impedance control. These differences were attributed solely to higher levels of voluntary background activity in the nondominant biarticular muscles, indicating that feedforward strategies for postural stability may differ between arms. Reflex sensitivity, which was defined as the magnitude of the reflex response for matched levels of background activity, was not significantly different between arms for a broad subject population ranging from 23 to 51 years of age. These results indicate that inter-arm differences in feedforward strategies are more influential during posture than differences in feedback sensitivity, in a broad subject population. Interestingly, restricting our analysis to subjects under 40 years of age revealed a small increase in long-latency reflex sensitivity in the nondominant arm relative to the dominant arm. Though our subject numbers were small for this secondary analysis, it suggests that further studies may be required to assess the influence of reflex lateralization throughout development.
影响因子：
2.5
作者：
Krutky, Matthew A.;Ravichandran, Vengateswaran J.;Perreault, Eric J.
通讯作者：
Perreault, Eric J.
影响因子：
2.5
作者：
Bagesteiro, LB;Sainburg, RL
通讯作者：
Sainburg, RL