Effect of motor planning on use of motor abundance
Effect of motor planning on use of motor abundance
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DOI：
10.1016/j.neulet.2007.02.037
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发表时间：
2007-04-24
影响因子：
2.5
通讯作者：
Stehman, Andrea Janelle
中科院分区：
文献类型：
--
作者：
de Freitas, Sandra Maria Sbeghen Ferreira;Scholz, John Peter;Stehman, Andrea Janelle
本研究探讨的假设，在何种程度上，电机冗余是用来协调关节运动达到电机规划的影响和增强时，任务需要更大的运动灵活性。受试者达到手臂的长度相同的中央放置的目标的条件下，目标位置是确定的或不确定的，使用一个双步骤的范例。通过将每个百分距离处关节配置的跨试验方差划分为对应于使用不同关节角度组合以实现等效手部位置（GEV）的分量和导致可变手部位置的分量来评估该假设位置（NGEV）。沿着路径的指针尖端移动变异性和可变目标误差在条件之间没有差异。较大的整体联合方差被发现为不确定的目标条件。这种增加的大部分是GEV，这是显着更高的不确定条件下控制的运动范围和运动方向。相比之下，NGEV不同的两个条件之间的运动范围的控制早期达到，这表明，目标的不确定性导致试验间的时间变化沿着的运动path.Results表明，更灵活的模式，关节协调时，神经系统必须计划达到运动到一个不确定的目标方向。(c)2007爱思唯尔爱尔兰有限公司保留所有权利。
This study examined the hypothesis that the degree to which motor redundancy is used to coordinate joint motions for reaching is influenced by motor planning and enhanced when the task requires greater movement flexibility. Subjects reached at arm's length to the same centrally placed target under conditions where the target location was either certain or uncertain, using a double-step paradigm. The hypothesis was evaluated by partitioning the across-trials variance of the joint configuration at each percent of the reach into a component corresponding to the use of different joint angle combinations to achieve an equivalent hand position (GEV) and a component leading to a variable hand position (NGEV). Pointer-tip movement variability along the path and variable targeting error did not differ between conditions. Larger overall joint variance was found for the uncertain target condition. Most of this increase was GEV, which was significantly higher in the uncertain condition for control of both movement extent and movement direction. In contrast, NGEV differed between the two conditions only for the control of movement extent early in the reach, suggesting that target uncertainty led to inter-trial timing variability along the movement path. The results suggest that more flexible patterns of joint coordination are used when the nervous system must plan reaching movements to an uncertain target direction. (c) 2007 Elsevier Ireland Ltd. All rights reserved.