Soechting J F, Buneo C A, Herrmann U, Flanders M
Department of Physiology, University of Minnesota, Minneapolis 55455, USA.
J Neurosci. 1995 Sep;15(9):6271-80. doi: 10.1523/JNEUROSCI.15-09-06271.1995.
Donders' law, as applied to the arm, predicts that to every location of the hand in space there corresponds a unique posture of the arm as defined by shoulder and elbow angles. This prediction was tested experimentally by asking human subjects to make pointing movements to a select number of target locations starting from a wide range of initial hand locations. The posture of the arm was measured at the start and end of every movement by means of video cameras. It was found that, in general, the posture of the arm at a given hand location does depend on the starting location of the movement and that, consequently, Donders' law is violated in this experimental condition. Kinematic and kinetic factors that could account for the variations in arm posture were investigated. It proved impossible to predict the final posture of the arm purely from kinematics, based on the initial posture of the arm. One hypothesis was successful in predicting final arm postures, namely that the final posture minimizes the amount of work that must be done to transport the arm from the starting location.
应用于手臂的东德斯定律预测，对于空间中手部的每个位置，都对应着一种由肩部和肘部角度定义的独特手臂姿势。通过要求人类受试者从广泛的初始手部位置开始，向选定的多个目标位置进行指向运动，对这一预测进行了实验测试。在每次运动的开始和结束时，通过摄像机测量手臂的姿势。结果发现，一般来说，在给定手部位置时手臂的姿势确实取决于运动的起始位置，因此，在这种实验条件下，东德斯定律被违背了。研究了可能导致手臂姿势变化的运动学和动力学因素。事实证明，仅根据手臂的初始姿势从运动学角度无法预测手臂的最终姿势。有一个假设成功地预测了手臂的最终姿势，即最终姿势使将手臂从起始位置移动所需完成的工作量最小化。
