Composition and decomposition in bimanual dynamic learning.
Composition and decomposition in bimanual dynamic learning.
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DOI：
10.1523/jneurosci.3473-08.2008
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发表时间：
2008-10-15
影响因子：
5.3
通讯作者：
Wolpert, Daniel M.
中科院分区：
文献类型：
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作者：
Howard, Ian S.;Ingram, James N.;Wolpert, Daniel M.
我们熟练地操纵物体的能力通常涉及运动系统学习以补偿物体的动力学。当两只手臂学会操纵一个物体时，它们可以合作，而当它们操纵单独的物体时，它们独立地控制每个物体。我们研究了如何学习这两个双手的情况下，通过施加力场的武器之间的转移。在一个耦合的情况下，一个单一的动态之间共享的武器，并在一个非耦合的情况下，单独的动态是由每个arm.In组成实验中，我们发现，当受试者已经学会了非耦合力场，他们能够转移到一个耦合场，这是两个字段的总和。然而，随着时间的推移，每个臂的贡献重新分配，因此，当它们返回到非耦合场时，误差最初增加，但很快恢复到以前的水平。在分解实验中，受试者学习了耦合场后，当暴露于非耦合场时，他们的错误增加了，非耦合场是耦合场的正交分量。然而，当重新引入耦合场时，受试者迅速重新适应。这些结果表明，非耦合和耦合的背景下的动力学表示是部分独立的。我们发现了额外的支持这一假设的显着学习相反的旋度场时，上下文，耦合与非耦合，交替与旋度场方向。这些结果表明，运动系统是能够使用部分单独的表示的动力学的两个手臂作用于一个单一的对象和两个手臂作用于单独的对象。
Our ability to skillfully manipulate an object often involves the motor system learning to compensate for the dynamics of the object. When the two arms learn to manipulate a single object they can act cooperatively, whereas when they manipulate separate objects they control each object independently. We examined how learning transfers between these two bimanual contexts by applying force fields to the arms. In a coupled context, a single dynamic is shared between the arms, and in an uncoupled context separate dynamics are experienced independently by each arm. In a composition experiment, we found that when subjects had learned uncoupled force fields they were able to transfer to a coupled field that was the sum of the two fields. However, the contribution of each arm repartitioned over time so that, when they returned to the uncoupled fields, the error initially increased but rapidly reverted to the previous level. In a decomposition experiment, after subjects learned a coupled field, their error increased when exposed to uncoupled fields that were orthogonal components of the coupled field. However, when the coupled field was reintroduced, subjects rapidly readapted. These results suggest that the representations of dynamics for uncoupled and coupled contexts are partially independent. We found additional support for this hypothesis by showing significant learning of opposing curl fields when the context, coupled versus uncoupled, was alternated with the curl field direction. These results suggest that the motor system is able to use partially separate representations for dynamics of the two arms acting on a single object and two arms acting on separate objects.