Retention and interference of learned dexterous manipulation: interaction between multiple sensorimotor processes
Retention and interference of learned dexterous manipulation: interaction between multiple sensorimotor processes
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DOI：
10.1152/jn.00348.2014
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发表时间：
2015-01-01
影响因子：
2.5
通讯作者：
Santello, Marco
中科院分区：
文献类型：
--
作者：
Fu, Qiushi;Santello, Marco
一个物体可以在多种情况下使用，每种情况都需要不同的手部动作。中枢神经系统如何建立和维持对这种灵巧操作的记忆仍不清楚。我们进行了实验，其中人类受试者必须学习并回忆在两种环境（A 和 B）中执行的操作。这两种环境都涉及举起同一个 L 形物体，该物体的几何形状暗示了其不对称的质量分布。正确的性能要求在物体提升开始时在垂直手柄上产生扭矩以防止其倾斜。扭矩方向取决于上下文，即对象方向，该方向通过对象绕垂直轴旋转 180 度而改变。通过 A(1)B(1)A(2) 上下文切换范式，受试者在八次试验的第一部分中学习了 A(1)，如扭矩接近所需的扭矩所示。然而，当受试者在 A(1) 之后立即切换到 B-1 时（负迁移），以及在通过另一组 8 个电梯学习 B 后切换到 A(2) 时必须回忆起 A(1) 时（检索干扰），受试者在预期所需扭矩方面犯了很大的错误。经典的感觉运动学习理论将这种干扰归因于内部模型的多速率、多状态错误驱动的更新。然而，通过系统地改变块间休息时间和块内试验次数，我们的结果提出了干扰和灵巧操作保留的另一种解释。具体来说，我们通过一种新颖的计算模型识别并量化了两种感觉运动机制之间的非线性相互作用：短暂的、上下文无关的、依赖于使用的感觉运动记忆和上下文敏感的、基于错误的学习过程。
An object can be used in multiple contexts, each requiring different hand actions. How the central nervous system builds and maintains memory of such dexterous manipulations remains unclear. We conducted experiments in which human subjects had to learn and recall manipulations performed in two contexts, A and B. Both contexts involved lifting the same L-shaped object whose geometry cued its asymmetrical mass distribution. Correct performance required producing a torque on the vertical handle at object lift onset to prevent it from tilting. The torque direction depended on the context, i.e., object orientation, which was changed by 180 degrees object rotation about a vertical axis. With an A(1)B(1)A(2) context switching paradigm, subjects learned A(1) in the first block of eight trials as indicated by a torque approaching the required one. However, subjects made large errors in anticipating the required torque when switching to B-1 immediately after A(1) (negative transfer), as well as when they had to recall A(1) when switching to A(2) after learning B through another block of eight lifts (retrieval interference). Classic sensorimotor learning theories attribute such interferences to multi-rate, multistate error-driven updates of internal models. However, by systematically changing the interblock break duration and within-block number of trials, our results suggest an alternative explanation underlying interference and retention of dexterous manipulation. Specifically, we identified and quantified through a novel computational model the nonlinear interaction between two sensorimotor mechanisms: a shortlived, context-independent, use-dependent sensorimotor memory and a context-sensitive, error-based learning process.