Clark J E, Phillips S J
Department of Kinesiology, University of Maryland, College Park 20742-2611.
Child Dev. 1993 Aug;64(4):1143-57.
Using a dynamical systems approach, we examined the development of intralimb coordination over the first year of independent walking. The segmental motion of the thigh and shank and their intralimb coordinative relationship were modeled dynamically as a system of coupled limit cycles. To test the predictions of such a dynamic model in the development of intralimb coordination, 3 infants were filmed from the onset of their first upright independent walking steps, and weekly for the next month and then every month thereafter until they had been walking for 1 year. 3 adults also were included for comparison. Analysis of the kinematic data derived from the film revealed that at the emergence of walking, the limit cycle system displayed instability in several aspects. With walking experience, however, the limit cycle regime became more attractive, such that by 3 months of walking the infants appeared to have found an adult-like stable coordinative relationship between the 2 segments. This pattern of instability followed by stability is consistent with the transitional behaviors of dynamical systems. Several potential control parameters are discussed that might contribute to the stabilization of the walking behavior. The utility of employing a dynamical systems approach for understanding developing behavioral systems is discussed.
我们采用动态系统方法，研究了独立行走第一年中肢体内部协调性的发展。大腿和小腿的节段性运动及其肢体内部的协调关系被动态建模为一个耦合极限环系统。为了检验这种动态模型在肢体内部协调性发展方面的预测，对3名婴儿从首次直立独立行走开始拍摄，在接下来的一个月每周拍摄一次，之后每月拍摄一次，直至他们行走满1年。还纳入了3名成年人作为对照。对从影片中获取的运动学数据的分析表明，在行走初现之时，极限环系统在几个方面表现出不稳定性。然而，随着行走经验的积累，极限环状态变得更具吸引力，以至于到行走3个月时，婴儿似乎已在这两个节段之间建立起类似成人的稳定协调关系。这种从不稳定到稳定的模式与动态系统的过渡行为相一致。讨论了几个可能有助于稳定行走行为的潜在控制参数。还讨论了采用动态系统方法理解行为系统发展的效用。
