NREM2 and sleep spindles are instrumental to the consolidation of motor sequence memories

Although numerous studies have convincingly demonstrated that sleep plays a critical role in motor sequence learning (MSL) consolidation, the specific contribution of the different sleep stages in this type of memory consolidation is still contentious. To probe the role of stage 2 non-REM sleep (NREM2) in this process, we used a conditioning protocol in three different groups of participants who either received an odor during initial training on a motor sequence learning task and were re-exposed to this odor during different sleep stages of the post-training night (i.e., NREM2 sleep [Cond-NREM2], REM sleep [Cond-REM], or were not conditioned during learning but exposed to the odor during NREM2 [NoCond]). Results show that the Cond-NREM2 group had significantly higher gains in performance at retest than both the Cond-REM and NoCond groups. Also, only the Cond-NREM2 group yielded significant changes in sleep spindle characteristics during cueing. Finally, we found that a change in frequen...尽管已有大量研究确凿证实，睡眠在运动序列学习（motor sequence learning, MSL）的记忆巩固过程中发挥着关键作用，但不同睡眠阶段在该类记忆巩固中的具体贡献仍存在争议。为探究第二阶段非快速眼动睡眠（stage 2 non-REM sleep, NREM2）在该过程中的作用，我们采用条件化实验范式，将被试划分为三组：第一组在运动序列学习任务的初始训练阶段接受气味刺激，并于训练后夜间的不同睡眠阶段再次暴露于该气味——具体为第二阶段非快速眼动睡眠阶段[Cond-NREM2]；第二组同样在训练时接受气味刺激，但于快速眼动睡眠（rapid eye movement sleep, REM）阶段再次暴露[Cond-REM]；第三组在学习阶段未接受条件化刺激，但在第二阶段非快速眼动睡眠期间暴露于气味[NoCond]。实验结果显示，在重测阶段，Cond-NREM2组的行为表现提升幅度显著高于Cond-REM组与NoCond组。此外，仅Cond-NREM2组在气味线索提示期间，其睡眠纺锤波特征出现了显著变化。最后，我们发现______的频率出现变化……