UPMC University, Paris 06, UMR 7222, ISIR, Paris, France.
J Neurophysiol. 2010 Aug;104(2):1090-102. doi: 10.1152/jn.00162.2010. Epub 2010 Jun 10.
Posture and movement are fundamental, intermixed components of motor coordination. Current approaches consider either that 1) movement is an active, anticipatory process and posture is a passive feedback process or 2) movement and posture result from a common passive process. In both cases, the presence of a passive component renders control scarcely robust and stable in the face of transmission delays and low feedback gains. Here we show in a model that posture and movement could result from the same active process: an optimal feedback control that drives the body from its estimated state to its goal in a given (planning) time by acting through muscles on the insertion position (bias) of compliant linkages (tendons). Computer simulations show that iteration of this process in the presence of noise indifferently produces realistic postural sway, fast goal-directed movements, and natural transitions between posture and movement.
姿势和运动是运动协调的基本、混合组成部分。目前的方法要么认为 1）运动是一种主动的、预期的过程，姿势是一种被动的反馈过程，要么认为 2）运动和姿势是由共同的被动过程产生的。在这两种情况下，由于存在被动成分，在面对传输延迟和低反馈增益时，控制几乎不稳健和稳定。在这里，我们在一个模型中表明，姿势和运动可能是由相同的主动过程产生的：一种最优的反馈控制，通过作用于柔顺连杆（肌腱）的插入位置（偏差）上的肌肉，在给定的（规划）时间内，将身体从其估计状态驱动到其目标，从而产生姿势摆动、快速目标导向运动和姿势与运动之间的自然转换。计算机模拟表明，在存在噪声的情况下，迭代该过程会产生现实的姿势摆动、快速的目标导向运动以及姿势和运动之间的自然转换。
