「練習ハ不可能ヲ可能二ス」の教訓にあるように，日々の練習の積み重ねによって運動技能は向上するが，近年，練習間に休憩をとることがスキルの獲得を促進する可能性が報告され，「マイクロオフライン学習」の概念が提唱されつつある．しかし，どのようなタイプの運動学習にもこれが当てはまるのか？／休憩をどのように過ごすことが学習にとってベストなのか？といった点についての検討はなされていない．本研究はこの点を実験的に検討していくことで，マイクロオフライン学習の概念をスポーツや楽器演奏の現場に広めることを目指す．
本研究では，2023年度に学習内容が自明な明示的学習を，2024年度・2025年度に明示的に理解し難い暗黙的学習を対象に複数の実験を積み上げ，異なる適応プロセスにより実現されると考えられる複数の運動学習課題において，①課題間の休息が学習を促進するか（マイクロオフライン学習が観察されるか）？；②課題間に運動想起を行うことがマイクロオフライン学習をどのように変調させるか？の2点に着目して研究を推進することを計画している．2023年度には明示的学習の一例として，手指によるシークエンス学習を対象に検証を行った．
16名の健常成人男女を対象に特定の配列（5桁の数列）を非利き手でなるべく早く繰り返し入力するシークエンス課題を行わせた．10秒1セットとし，10秒間インターバルを挟みながらこれを30セット行わせた．セット内の最初と最後のシークエンスにかかった時間の差異をマイクロオンライン学習量（＝練習中に学習がどのように進んだか），セット間の最後と最初のシークエンスにかかった時間の差異をマイクロオフライン学習量（＝休息中に学習がどのように進んだか）として，定量評価した．その結果，インターバルに休息を挟んだRest条件ではマイクロオフライン学習がしっかりと観察されたのに対して，インターバルに運動想起をおこなったRecall条件ではマイクロオフライン学習が阻害された．つまり，ここで用いたような明示的学習においては，インターバルはしっかりと休息を挟むことが肝要であり，意識的な運動想起が運動の自動化をかえって阻害したのではないかと考えられた．
As the dictum "Practice makes the impossible possible," motor skills improve through daily practice. Recently, however, it has been reported that taking short periods of rest between practices may facilitate skill acquisition, and the concept of "micro-offline learning" is being proposed. However, does this apply to any type of motor learning? How should we spend the rests for learning? This study aims to experimentally examine these points and to spread the concept of micro-offline learning to the field of sports and musical instrument performance.
In this study, we will conduct multiple experiments from 2023 to 2025. In 2023, I target explicit learning which we can understand the learning content self-explanatory. In 2024-2-25, I target implicit learning which we can hardly understand the learning contents explicitly. Regarding each type of motor learning, we will examine the following points: 1) Whether the short period of rests between practices facilitates learning (i.e., whether micro-offline learning is observed)? (2) How does motor recall between tasks modulate micro-offline learning? In FY2023, we conducted a study on hand-sequence learning as an example of explicit learning.
Sixteen healthy adults were required to perform a sequence task in which they repeatedly input a specific sequence (5-digit number sequence) as quickly as possible with their non-dominant hand. 30 sets of the task with 10-second intervals between sets were performed. The difference in the time taken for the first and last sequences within a set was quantitatively evaluated as the amount of micro-online learning (i.e., how learning progressed during practice), and the difference in the time taken for the last and first sequences between sets was quantitatively evaluated as the amount of micro-offline learning (i.e., how learning progressed during rest). The results showed that micro-offline learning was observed in the Rest condition where participants only took breaks during the interval, whereas micro-offline learning was inhibited in the Recall condition where they made efforts to imagine the practiced sequence during the interval. Thus, in explicit learning such as the one used here, it is essential that the interval be interspersed with a rest period, and conscious motor recall may actually inhibit motor automaticity.