Shiga Kyosuke, Miyaguchi Shota, Inukai Yasuto, Otsuru Naofumi, Onishi Hideaki
Graduate School, Niigata University of Health and Welfare, Niigata 950-3198, Japan.
Institute for Human Movement and Medical Sciences, Niigata University of Health and Welfare, Niigata 950-3198, Japan.
Behav Brain Res. 2024 Feb 29;459:114770. doi: 10.1016/j.bbr.2023.114770. Epub 2023 Nov 19.
A theory has been posited that microscale learning, which involves short intervals of a few seconds during explicit motor skill learning, considerably enhances performance. This phenomenon correlates with diminished beta-band activity in the frontal and parietal regions. However, there is a lack of neurophysiological studies regarding the relationship between microscale learning and implicit motor skill learning. In the present study, we aimed to determine the effects of transcranial alternating current stimulation (tACS) during short rest periods on microscale learning in an implicit motor task. We investigated the effects of 20-Hz β-tACS delivered during short rest periods while participants performed an implicit motor task. In Experiments 1 and 2, β-tACS targeted the right dorsolateral prefrontal cortex and the right frontoparietal network, respectively. The participants performed a finger-tapping task using their nondominant left hand, and microscale learning was separately analyzed for micro-online gains (MOnGs) and micro-offline gains (MOffGs). Contrary to our expectations, β-tACS exhibited no statistically significant effects on MOnGs or MOffGs in either Experiment 1 or Experiment 2. In addition, microscale learning during the performance of the implicit motor task was improved by MOffGs in the early learning phase and by MOnGs in the late learning phase. These results revealed that the stimulation protocol employed in this study did not affect microscale learning, indicating a novel aspect of microscale learning in implicit motor tasks. This is the first study to examine microscale learning in implicit motor tasks and may provide baseline information that will be useful in future studies.
有一种理论认为，微观学习（即在明确的运动技能学习过程中涉及几秒钟的短时间间隔）能显著提高表现。这种现象与额叶和顶叶区域的β波段活动减少有关。然而，关于微观学习与内隐运动技能学习之间的关系，缺乏神经生理学研究。在本研究中，我们旨在确定在短暂休息期间经颅交流电刺激（tACS）对一项内隐运动任务中的微观学习的影响。我们研究了在参与者执行一项内隐运动任务时，在短暂休息期间施加20赫兹β-tACS的效果。在实验1和实验2中，β-tACS分别针对右侧背外侧前额叶皮层和右侧额顶叶网络。参与者用其非优势左手执行一项手指敲击任务，并分别针对微观在线增益（MOnGs）和微观离线增益（MOffGs）分析微观学习情况。与我们的预期相反，在实验1或实验2中，β-tACS对MOnGs或MOffGs均未表现出统计学上的显著影响。此外，在早期学习阶段，MOffGs改善了内隐运动任务执行过程中的微观学习，而在后期学习阶段，MOnGs起到了改善作用。这些结果表明，本研究采用的刺激方案并未影响微观学习，这揭示了内隐运动任务中微观学习的一个新方面。这是第一项研究内隐运动任务中微观学习的研究，可能会为未来的研究提供有用的基线信息。
