University of South Carolina School of Medicine Greenville, Greenville, South Carolina.
Department of Psychology and Program in Neuroscience, Furman University, Greenville, South Carolina.
PLoS One. 2020 Feb 13;15(2):e0220419. doi: 10.1371/journal.pone.0220419. eCollection 2020.
Across a broad spectrum of memory tasks, retention is superior following a night of sleep compared to a day of wake. However, this result alone does not clarify whether sleep merely slows the forgetting that would otherwise occur as a result of information processing during wakefulness, or whether sleep actually consolidates memories, protecting them from subsequent retroactive interference. Two influential studies suggested that sleep protects memories against the subsequent retroactive interference that occurs when participants learn new yet overlapping information (interference learning). In these studies, interference learning was much less detrimental to memory following a night of sleep compared to a day of wakefulness, an indication that sleep supports this important aspect of memory consolidation. In the current replication study, we repeated the protocol of and, additionally, we examined the impact of intrinsic motivation on performance in sleep and wake participants. We were unable to replicate the finding that sleep protects memories against retroactive interference, with the detrimental effects of interference learning being essentially the same in wake and sleep participants. We also found that while intrinsic motivation benefitted task acquisition it was not a modulator of sleep-wake differences in memory processing. Although we cannot accept the null hypothesis that sleep has no role to play in reducing the negative impact of interference, the findings draw into question prior evidence for sleep's role in protecting memories against interference. Moreover, the current study highlights the importance of replicating key findings in the study of sleep's impact on memory processing before drawing strong conclusions that set the direction of future research.
在广泛的记忆任务中，与白天保持清醒相比，睡眠后保留信息的能力更强。然而，仅这一结果并不能明确睡眠是否仅仅减缓了因白天清醒时的信息处理而导致的遗忘，或者睡眠是否实际上巩固了记忆，从而防止了随后的回溯性干扰。两项有影响力的研究表明，睡眠可以保护记忆免受随后的回溯性干扰，而回溯性干扰发生在参与者学习新的但重叠的信息（干扰学习）时。在这些研究中，与白天保持清醒相比，睡眠后进行干扰学习对记忆的损害要小得多，这表明睡眠支持记忆巩固的这一重要方面。在当前的复制研究中，我们重复了[1]和[2]的实验方案，此外，我们还研究了内在动机对睡眠和清醒参与者表现的影响。我们无法复制睡眠保护记忆免受回溯性干扰的发现，干扰学习的不利影响在清醒和睡眠参与者中基本相同。我们还发现，虽然内在动机有益于任务的获取，但它不是睡眠-清醒记忆处理差异的调节因素。尽管我们不能接受睡眠在减少干扰的负面影响方面没有作用的假设，但这些发现对睡眠在保护记忆免受干扰方面的作用提出了质疑。此外，当前的研究强调了在得出关于睡眠对记忆处理影响的强有力结论之前，在复制睡眠影响记忆处理的关键发现方面的重要性，这些结论为未来的研究指明了方向。
