Movement speed effects on limb position drift
Movement speed effects on limb position drift
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DOI：
10.1007/s00221-003-1601-7
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发表时间：
2003-11-01
影响因子：
2
通讯作者：
Sainburg, RL
中科院分区：
文献类型：
--
作者：
Brown, LE;Rosenbaum, DA;Sainburg, RL
先前的研究表明，即使在连续盲操作过程中肢体位置发生了明显的漂移，生成的手路径的拓扑和测量特性仍然保持显著不变。我们测试了这一有趣效应的两种可能的解释。根据一种假设，位置漂移是由于肢体位置信息的退化。这一假设预测，在运动逆转时静态手位置的漂移不应取决于运动速度。根据另一种假设，位置漂移是由于运动信息的退化。这一假说预测，在运动逆转时，静态手位的漂移应该随运动速度而变化。我们通过改变正常成年人在没有视觉反馈的情况下来回进行手动定位运动所需的运动速度来测试这两种假设。移动距离和方向被很好地保存了下来，尽管移动之间的手的位置发生了很大的变化。与运动误差假设一致，但与位置假设不一致，手的位置漂移速率取决于运动速度。这些数据与定义轨迹控制坐标系原点的手部位置和运动轨迹由不同的神经机制控制的观点一致。
Previous research has shown that even when limb position drifts considerably during continuous blind performance, the topological and metrical properties of generated hand paths remain remarkably invariant. We tested two possible accounts of this intriguing effect. According to one hypothesis, position drift is due to degradation of limb-position information. This hypothesis predicted that drift of static hand positions at movement reversals should not depend on movement speed. According to the other hypothesis, position drift is due to degradation of movement information. This hypothesis predicted that drift of static hand positions at movement reversals should vary with movement speed. We tested these two hypotheses by varying the required movement speed when normal human adults performed back-and-forth manual positioning movements in the absence of visual feedback. Movement distance and direction were well preserved even though hand positions between movements drifted considerably. In accord with the movement error hypothesis, but not in accord with the position hypothesis, the rate at which hand positions drifted depended on movement speed. The data are consistent with the idea that hand position, which defines the origin of the trajectory control coordinate system, and movement trajectory are controlled by distinct neural mechanisms.