Control of movement variability and the regulation of limb impedance.
Control of movement variability and the regulation of limb impedance.
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DOI：
10.1152/jn.00970.2007
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发表时间：
2007-12
影响因子：
2.5
通讯作者：
D. Lametti;Guillaume Houle;D. Ostry
中科院分区：
文献类型：
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作者：
D. Lametti;Guillaume Houle;D. Ostry
人类通常会向不同方向上具有不同精度要求的目标进行移动。例子从日常发生的事情，如抓住咖啡杯的手柄，到外科医生定位手术刀的更精细的例子。在这种情况下达到准确性可能与神经系统调节肢体对位移的抵抗力或阻抗的能力有关。为了验证这个想法，受试者从随机的起始位置移动到具有形状依赖精度要求的目标。我们使用机器人设备来评估肢体阻抗和运动变异性模式，就像受试者到达目标一样。我们表明，在所需的精度是高的方向上的阻抗增加。独立的目标形状，肢体僵硬的模式被认为是预测运动变异的空间模式。因此，神经系统可以在完全可预测的环境中调节肢体阻抗，以帮助达到准确性。
Humans routinely make movements to targets that have different accuracy requirements in different directions. Examples extend from everyday occurrences such as grasping the handle of a coffee cup to the more refined instance of a surgeon positioning a scalpel. The attainment of accuracy in situations such as these might be related to the nervous system's capacity to regulate the limb's resistance to displacement, or impedance. To test this idea, subjects made movements from random starting locations to targets that had shape-dependent accuracy requirements. We used a robotic device to assess both limb impedance and patterns of movement variability just as the subject reached the target. We show that impedance increases in directions where required accuracy is high. Independent of target shape, patterns of limb stiffness are seen to predict spatial patterns of movement variability. The nervous system is thus seen to modulate limb impedance in entirely predictable environments to aid in the attainment of reaching accuracy.