Rein Robert, Davids Keith, Button Chris
Groupe de Recherche Apprentissage et Contexte, Ecole des Hautes Etudes en Sciences Sociales, Paris, France.
Exp Brain Res. 2010 Mar;201(2):307-22. doi: 10.1007/s00221-009-2040-x. Epub 2009 Oct 23.
The identification of attractors is one of the key tasks in studies of neurobiological coordination from a dynamical systems perspective, with a considerable body of literature resulting from this task. However, with regards to typical movement models investigated, the overwhelming majority of actions studied previously belong to the class of continuous, rhythmical movements. In contrast, very few studies have investigated coordination of discrete movements, particularly multi-articular discrete movements. In the present study, we investigated phase transition behavior in a basketball throwing task where participants were instructed to shoot at the basket from different distances. Adopting the ubiquitous scaling paradigm, throwing distance was manipulated as a candidate control parameter. Using a cluster analysis approach, clear phase transitions between different movement patterns were observed in performance of only two of eight participants. The remaining participants used a single movement pattern and varied it according to throwing distance, thereby exhibiting hysteresis effects. Results suggested that, in movement models involving many biomechanical degrees of freedom in degenerate systems, greater movement variation across individuals is available for exploitation. This observation stands in contrast to movement variation typically observed in studies using more constrained bi-manual movement models. This degenerate system behavior provides new insights and poses fresh challenges to the dynamical systems theoretical approach, requiring further research beyond conventional movement models.
从动态系统的角度来看，识别吸引子是神经生物学协调研究中的关键任务之一，由此产生了大量的文献。然而，就所研究的典型运动模型而言，先前研究的绝大多数动作都属于连续的、有节奏的运动类别。相比之下，很少有研究调查离散运动的协调性，特别是多关节离散运动。在本研究中，我们调查了篮球投篮任务中的相变行为，参与者被要求从不同距离投篮。采用普遍存在的标度范式，将投篮距离作为候选控制参数进行操控。使用聚类分析方法，在八名参与者中只有两名参与者的表现中观察到不同运动模式之间的明显相变。其余参与者使用单一运动模式，并根据投篮距离进行变化，从而表现出滞后效应。结果表明，在涉及退化系统中许多生物力学自由度的运动模型中，个体间更大的运动变化可供利用。这一观察结果与使用更受限的双手运动模型的研究中通常观察到的运动变化形成对比。这种退化系统行为为动态系统理论方法提供了新的见解，并带来了新的挑战，需要超越传统运动模型进行进一步研究。
