Admiraal Marjan A, Kusters Martijn J M A M, Gielen Stan C A M
Department of Biophysics, University of Nijmegen, the Netherlands.
Motor Control. 2004 Jul;8(3):312-38. doi: 10.1123/mcj.8.3.312.
A central problem in motor control relates to the coordination of the arm's many degrees of freedom. This problem concerns the many arm postures (kinematics) that correspond to the same hand position in space and the movement trajectories between begin and end position (dynamics) that result in the same arm postures. The aim of this study was to compare the predictions for arm kinematics by various models on human motor control with experimental data and to study the relation between kinematics and dynamics. Goal-directed arm movements were measured in 3-D space toward far and near targets. The results demonstrate that arm postures for a particular target depend on previous arm postures, contradicting Donders's law. The minimum-work and minimum-torque-change models, on the other hand, predict a much larger effect of initial posture than observed. These data suggest that both kinematics and dynamics affect postures and that their relative contribution might depend on instruction and task complexity.
运动控制中的一个核心问题与手臂多个自由度的协调有关。这个问题涉及到许多与空间中相同手部位置相对应的手臂姿势（运动学），以及在起始和结束位置之间导致相同手臂姿势的运动轨迹（动力学）。本研究的目的是将各种人类运动控制模型对手臂运动学的预测与实验数据进行比较，并研究运动学与动力学之间的关系。在三维空间中测量了朝向远近目标的目标导向手臂运动。结果表明，特定目标的手臂姿势取决于先前的手臂姿势，这与唐德斯定律相矛盾。另一方面，最小功和最小扭矩变化模型预测的初始姿势影响比观察到的要大得多。这些数据表明，运动学和动力学都会影响姿势，它们的相对贡献可能取决于指令和任务复杂性。
