Département de Physiologie, Université de Montréal, Montréal, QC, Canada.
J Neurophysiol. 2011 Jun;105(6):3022-33. doi: 10.1152/jn.00975.2010. Epub 2011 Mar 30.
There is considerable debate on the extent to which biomechanical properties of movements are taken into account before and during voluntary movements. For example, while several models have described reach planning as primarily kinematic, some studies have suggested that implicit knowledge about biomechanics may also exert some influence on the planning of reaching movements. Here, we investigated whether decisions about reaching movements are influenced by biomechanical factors and whether these factors are taken into account before movement onset. To this end, we designed an experimental paradigm in which humans made free choices between two potential reaching movements where the options varied in path distance as well as biomechanical factors related to movement energy and stability. Our results suggest that the biomechanical properties of potential actions strongly influence the selection between them. In particular, in our task, subjects preferred movements whose final trajectory was better aligned with the major axis of the arm's mobility ellipse, even when the launching properties were very similar. This reveals that the nervous system can predict biomechanical properties of potential actions before movement onset and that these predictions, in addition to purely abstract criteria, may influence the decision-making process.
在进行自主运动之前和期间，运动的生物力学特性在多大程度上被考虑，这存在相当大的争议。例如，虽然有几个模型将伸手规划描述为主要的运动学特性，但一些研究表明，关于生物力学的内隐知识也可能对伸手运动的规划产生一些影响。在这里，我们研究了伸手运动的决策是否受到生物力学因素的影响，以及这些因素是否在运动开始之前被考虑到。为此，我们设计了一个实验范式，在这个范式中，人类在两种潜在的伸手运动之间做出自由选择，其中选项在路径距离以及与运动能量和稳定性相关的生物力学因素方面有所不同。我们的结果表明，潜在动作的生物力学特性强烈影响着它们之间的选择。特别是在我们的任务中，即使发射特性非常相似，受试者也更喜欢最终轨迹与手臂可动性椭圆的主轴更好对齐的动作。这表明神经系统可以在运动开始之前预测潜在动作的生物力学特性，这些预测除了纯粹的抽象标准外，可能会影响决策过程。
