Abstract:
Targeted memory reactivation (TMR), or the presentation of learning-related cues during sleep, has been shown to benefit memory consolidation for specific memory traces when applied during non-rapid eye movement (NREM) sleep. Prior studies suggest that TMR during REM sleep may play a role in memory generalization processes, but evidence remains scarce. We tested the hypothesis that TMR exerts a differential effect on distinct mnemonic processes as a function of the sleep state (REM vs. NREM) in which TMR is delivered. Mnemonic discrimination and generalization of semantic categories were investigated using an adapted version of the Mnemonic Similarity Task, before and after sleep. Forty-eight participants encoded pictures from eight semantic categories, each associated with a sound. In the pre-sleep immediate test, they had to discriminate \"old\" (targets) from \"similar\" (lures) or \"new\" (foils) pictures. During sleep, half of the sounds were replayed in slow wave sleep (SWS) or REM sleep. Recognition, discrimination, and generalization memory indices were tested in the morning. These indices did not differ between SWS and REM TMR groups or reactivated and non-reactivated item categories. Additional results suggest a positive effect of TMR on performance for highly similar items mostly relying on mnemonic discrimination processes. During sleep, EEG activity after cue presentation increased in the delta-theta and sigma band in the SWS group, and in the beta band in the REM TMR group. These results do not support the hypothesis of a differential processing of novel memory traces when TMR is administered in distinctive physiological sleep states.
摘要:
目标记忆重新激活(TMR),或者在睡眠中呈现与学习相关的线索,已显示,当在非快速眼动(NREM)睡眠期间应用时,对特定记忆痕迹的记忆巩固有益。先前的研究表明,REM睡眠期间的TMR可能在记忆泛化过程中发挥作用,但证据仍然很少.我们检验了以下假设:TMR对睡眠状态的不同记忆过程产生不同的影响(REM与NREM)在其中交付TMR。使用经过改编的记忆相似度任务研究了语义类别的记忆区分和概括,睡觉前和睡觉后。48名参与者编码了来自8个语义类别的图片,每个都与声音有关。在睡前即时测试中,他们必须区分“老”(目标)和“类似”(诱饵)或“新”(箔)图片。在睡眠中,一半的声音在慢波睡眠(SWS)或REM睡眠中播放。认可,歧视,早上测试了泛化记忆指数。这些指数在SWS和REMTMR组或重新激活和非重新激活的项目类别之间没有差异。其他结果表明,TMR对高度相似的项目的性能有积极影响,这些项目大多依赖于记忆区分过程。在睡眠中,提示呈现后的EEG活动在SWS组中的δ-θ和σ带增加,在REMTMR组的β波段。这些结果不支持以下假设:当在独特的生理睡眠状态下施用TMR时,对新型记忆轨迹进行差异处理。