An implicit memory of errors limits human sensorimotor adaptation
An implicit memory of errors limits human sensorimotor adaptation
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DOI：
10.1038/s41562-020-01036-x
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发表时间：
2021-02-04
影响因子：
29.9
通讯作者：
Shadmehr, Reza
中科院分区：
文献类型：
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作者：
Albert, Scott T.;Jang, Jihoon;Shadmehr, Reza
人类的运动适应达到了上限。Albert等人报告说，这种限制与内隐学习有关。当扰动是可变的时，随着潜意识学习系统对误差的敏感性降低，适应极限降低。在扩展运动适应过程中，尽管残余误差持续存在，但学习似乎已经饱和。这种适应极限不是固定的，而是随扰动方差而变化的；方差越大，残差越大。这些总体适应的变化可能与内隐或外显学习系统有关。在这里，我们发现当适应完全依赖于外显系统时，残差消失，学习不受扰动变异性的影响。相反，当学习完全或部分依赖于内隐学习时，残余误差再次出现。在高变异环境中，总内隐适应的减少是由于错误敏感性的变化，而不是由于遗忘。这些观察结果表明，当错误在一致的方向上发生时，隐式系统对错误变得更加敏感。因此，运动适应中的残余误差至少部分是由内隐学习系统引起的，该系统根据过去错误的一致性调节其错误敏感性。
Human motor adaptation reaches an upper limit. Albert et al. report that this limit is linked to implicit learning. When perturbations are variable, the adaptation limit decreases as subconscious learning systems become less sensitive to error.During extended motor adaptation, learning appears to saturate despite persistence of residual errors. This adaptation limit is not fixed but varies with perturbation variance; when variance is high, residual errors become larger. These changes in total adaptation could relate to either implicit or explicit learning systems. Here, we found that when adaptation relied solely on the explicit system, residual errors disappeared and learning was unaltered by perturbation variability. In contrast, when learning depended entirely, or in part, on implicit learning, residual errors reappeared. Total implicit adaptation decreased in the high-variance environment due to changes in error sensitivity, not in forgetting. These observations suggest a model in which the implicit system becomes more sensitive to errors when they occur in a consistent direction. Thus, residual errors in motor adaptation are at least in part caused by an implicit learning system that modulates its error sensitivity in response to the consistency of past errors.