Wong Aaron L, Lindquist Martin A, Haith Adrian M, Krakauer John W
Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland;
Department of Biostatistics, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland;
J Neurophysiol. 2015 Jul;114(1):219-32. doi: 10.1152/jn.00218.2015. Epub 2015 Apr 22.
Motor skill learning involves a practice-induced improvement in the speed and/or accuracy of a discrete movement. It is often thought that paradigms involving repetitive practice of discrete movements performed in a fixed sequence result in a further enhancement of skill beyond practice of the individual movements in a random order. Sequence-specific performance improvements could, however, arise without practice as a result of knowledge of the sequence order; knowledge could operate by either enabling advanced motor planning of the known sequence elements or by increasing overall motivation. Here, we examined how knowledge and practice contribute to performance of a sequence of movements. We found that explicit knowledge provided through instruction produced practice-independent improvements in reaction time and execution quality. These performance improvements occurred even for random elements within a partially known sequence, indicative of a general motivational effect rather than a sequence-specific effect of advanced planning. This motivational effect suggests that knowledge influences performance in a manner analogous to reward. Additionally, practice led to similar improvements in execution quality for both known and random sequences. The lack of interaction between knowledge and practice suggests that any skill acquisition occurring during discrete sequence tasks arises solely from practice of the individual movement elements, independent of their order. We conclude that performance improvements in discrete sequence tasks arise from the combination of knowledge-based motivation and sequence-independent practice; investigating this interplay between cognition and movement may facilitate a greater understanding of the acquisition of skilled behavior.
运动技能学习涉及通过练习使离散动作的速度和/或准确性得到提高。人们通常认为，涉及按固定顺序重复练习离散动作的范式，会比以随机顺序单独练习这些动作更能提升技能。然而，特定序列的表现提升可能在没有练习的情况下因对序列顺序的了解而出现；这种了解可能通过对已知序列元素进行高级运动规划或通过增强整体动机来起作用。在这里，我们研究了知识和练习如何影响一系列动作的表现。我们发现，通过指导提供的明确知识在反应时间和执行质量方面产生了与练习无关的提升。即使对于部分已知序列中的随机元素，这些表现提升也会出现，这表明是一种普遍的动机效应，而非高级规划的特定序列效应。这种动机效应表明，知识以类似于奖励的方式影响表现。此外，练习使已知序列和随机序列的执行质量都得到了类似的提升。知识和练习之间缺乏相互作用表明，在离散序列任务中发生的任何技能习得都仅源于对单个动作元素的练习，而与它们的顺序无关。我们得出结论，离散序列任务中的表现提升源于基于知识的动机和与序列无关的练习的结合；研究认知与动作之间的这种相互作用可能有助于更深入地理解熟练行为的习得。
