Coxon James P, Peat Nicola M, Byblow Winston D
Movement Neuroscience Laboratory, Department of Sport & Exercise Science, The University of Auckland, Auckland, New Zealand; and Centre for Brain Research, The University of Auckland, Auckland, New Zealand.
Movement Neuroscience Laboratory, Department of Sport & Exercise Science, The University of Auckland, Auckland, New Zealand; and.
J Neurophysiol. 2014 Jul 1;112(1):156-64. doi: 10.1152/jn.00893.2013. Epub 2014 Apr 9.
Motor learning requires practice over a period of time and depends on brain plasticity, yet even for relatively simple movements, there are multiple practice strategies that can be used for skill acquisition. We investigated the role of intracortical inhibition in the primary motor cortex (M1) during motor skill learning. Event-related transcranial magnetic stimulation (TMS) was used to assess corticomotor excitability and inhibition thought to involve synaptic and extrasynaptic γ-aminobutyric acid (GABA). Short intracortical inhibition (SICI) was assessed using 1- and 2.5-ms interstimulus intervals (ISIs). Participants learned a novel, sequential pinch-grip task on a computer in either a repetitive or interleaved practice structure. Both practice structures showed equivalent levels of motor performance at the end of acquisition and at retention 1 wk later. There was a novel task-related modulation of 1-ms SICI. Repetitive practice elicited a greater reduction of 1- and 2.5-ms SICI, i.e., disinhibition, between rest and task acquisition, compared with interleaved practice. These novel findings support the use of a repetitive practice structure for motor learning because the associated effects within M1 have relevance for motor rehabilitation.
运动学习需要一段时间的练习，并且依赖于大脑可塑性，然而，即使对于相对简单的动作，也有多种可用于技能习得的练习策略。我们研究了运动技能学习过程中初级运动皮层（M1）内抑制的作用。采用事件相关经颅磁刺激（TMS）来评估被认为涉及突触和突触外γ-氨基丁酸（GABA）的皮质运动兴奋性和抑制。使用1毫秒和2.5毫秒的刺激间隔（ISI）评估短皮质内抑制（SICI）。参与者在计算机上以重复或交错练习结构学习一种新颖的、连续的捏握任务。在习得结束时和1周后的保持期，两种练习结构都表现出同等水平的运动表现。存在一种与任务相关的1毫秒SICI新调制。与交错练习相比，重复练习在休息和任务习得之间引起1毫秒和2.5毫秒SICI更大程度的降低，即去抑制。这些新发现支持在运动学习中使用重复练习结构，因为M1内的相关效应与运动康复有关。
