Farshchiansadegh Ali, Melendez-Calderon Alejandro, Ranganathan Rajiv, Murphey Todd D, Mussa-Ivaldi Ferdinando A
Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, Illinois, United States of America.
Department of Biomedical Engineering, Northwestern University, Evanston, Illinois, United States of America.
PLoS Comput Biol. 2016 Apr 1;12(4):e1004861. doi: 10.1371/journal.pcbi.1004861. eCollection 2016 Apr.
The laws of physics establish the energetic efficiency of our movements. In some cases, like locomotion, the mechanics of the body dominate in determining the energetically optimal course of action. In other tasks, such as manipulation, energetic costs depend critically upon the variable properties of objects in the environment. Can the brain identify and follow energy-optimal motions when these motions require moving along unfamiliar trajectories? What feedback information is required for such optimal behavior to occur? To answer these questions, we asked participants to move their dominant hand between different positions while holding a virtual mechanical system with complex dynamics (a planar double pendulum). In this task, trajectories of minimum kinetic energy were along curvilinear paths. Our findings demonstrate that participants were capable of finding the energy-optimal paths, but only when provided with veridical visual and haptic information pertaining to the object, lacking which the trajectories were executed along rectilinear paths.
物理定律决定了我们运动的能量效率。在某些情况下，比如移动，身体的力学原理在决定能量最优行动过程中起主导作用。在其他任务中，比如操作，能量消耗关键取决于环境中物体的可变属性。当这些运动需要沿着不熟悉的轨迹移动时，大脑能否识别并遵循能量最优运动？这种最优行为的发生需要哪些反馈信息？为了回答这些问题，我们要求参与者在握住一个具有复杂动力学的虚拟机械系统（平面双摆）时，将其优势手在不同位置之间移动。在这个任务中，最小动能的轨迹是沿着曲线路径的。我们的研究结果表明，参与者能够找到能量最优路径，但前提是要提供与物体相关的真实视觉和触觉信息，缺乏这些信息时，轨迹则是沿着直线路径执行的。
