The Dynamical Analysis of Inter-Trial Fluctuations Near Goal Equivalent Manifolds
The Dynamical Analysis of Inter-Trial Fluctuations Near Goal Equivalent Manifolds
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DOI：
10.1007/978-1-4939-1338-1_9
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发表时间：
2014-01-01
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影响因子：
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通讯作者：
Dingwell, Jonathan B.
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文献类型：
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作者：
Cusumano, Joseph P.;Mahoney, Joseph M.;Dingwell, Jonathan B.
利用任务流形的概念，许多数据分析方法已被用来解释冗余如何影响重复运动表现期间观察到的可变性结构。在这里，我们描述了将任务流形视角与试验间任务动态分析相结合的研究。目标等效流形 (GEM) 与最优控制思想一起用于制定简单模型，作为关于试验间波动如何产生和调节的可实验检验的假设。在实验环境中，这些现象学模型使我们能够展示如何围绕给定的 GEM 在时空上组织纠错控制。为了说明我们的方法，我们将其应用于研究虚拟沙狐球任务中观察到的变异性。 GEM 附近的 Inter-Trial 动力学的几何稳定性属性是从波动时间序列数据中提取的。我们发现受试者对垂直于 GEM 的本征方向上的波动表现出很强的控制能力，而他们对几乎但不完全与其相切的本征方向上的波动的控制却很弱。我们证明了我们的动态分析在坐标变换下是稳健的，并讨论了我们的结果如何支持最小干预原则的广义解释，该原则表明除了目标级误差最小化之外还涉及竞争成本。
Using the concept of task manifolds, a number of data analysis methods have been used to explain how redundancy influences the structure of variability observed during repeated motor performance. Here we describe investigations that integrate the task manifold perspective with the analysis of Inter-Trial task dynamics. Goal equivalent manifolds (GEMs), together with optimal control ideas, are used to formulate simple models that serve as experimentally testable hypotheses on how Inter-Trial fluctuations are generated and regulated. In an experimental context, these phenomenological models allow us to show how error-correcting control is spatiotemporally organized around a given GEM. To illustrate our approach, we apply it to study the variability observed in a virtual shuffleboard task. The geometric stability properties of the Inter-Trial dynamics near the GEM are extracted from fluctuation time series data. We find that subjects exhibit strong control of fluctuations in an eigendirection transverse to the GEM, whereas they only weakly control fluctuations in an eigendirection nearly, but not exactly, tangent to it. We demonstrate that our dynamical analysis is robust under coordinate transformations, and discuss how our results support a generalized interpretation of the minimum intervention principle that suggests the involvement of competing costs in addition to goal-level error minimization.