Cross Zachariah R, Santamaria Amanda, Coussens Scott W, Kohler Mark J
Northwestern University, Chicago, 60611, Illinois, United States of America; La Trobe University, 3086, Melbourne, Victoria, Australia.
University of South Australia, Adelaide, 5072, South Australia, Australia.
Neuropsychologia. 2025 Sep 4;219:109270. doi: 10.1016/j.neuropsychologia.2025.109270.
Sleep neurophysiology undergoes significant changes across the lifespan, which coincide with age-related differences in memory, particularly for emotional information. However, the mechanisms that underlie these effects remain poorly understood. One potential mechanism is the aperiodic component, which reflects "neural noise", differs across age, and is predictive of perceptual and cognitive processes. In this study, we investigated how intrinsic (i.e., resting-state) aperiodic neural activity modulates sleep-based emotional memory consolidation across the human lifespan. In a within-subjects, repeated measures design, forty-two participants aged 7-72 years (M = 26.60, SD = 17.45; 26 female) completed a learning and baseline recognition emotional memory task before a 2hr afternoon sleep opportunity and an equivalent period of wake. Recognition accuracy was also assessed post-delay. We found that aperiodic slopes follow a u-shaped trajectory across the lifespan: slopes flatten from childhood to young adulthood, before steepening thereafter, with this effect most prominent in frontal regions. Age-related differences in aperiodic slopes also explained interindividual differences in emotional memory consolidation, with less age-related flattening of slopes associated with stronger consolidation of negative stimuli post-sleep but not post-wake. Lastly, independent of aperiodic activity, age-related differences in NREM oscillatory activity predicted emotional memory consolidation. These findings suggest that the efficiency of sleep-based emotional memory consolidation is modulated by age-related differences in aperiodic neural and NREM oscillatory activities, providing novel insights into the neurophysiological mechanisms underpinning emotional memory across the lifespan.
睡眠神经生理学在整个生命周期中会发生显著变化，这与记忆中与年龄相关的差异相吻合，尤其是在处理情绪信息方面。然而，这些影响背后的机制仍知之甚少。一种潜在机制是非周期性成分，它反映了“神经噪声”，随年龄而异，并可预测感知和认知过程。在本研究中，我们调查了内在（即静息状态）非周期性神经活动如何在人类整个生命周期中调节基于睡眠的情绪记忆巩固。在一项被试内重复测量设计中，42名年龄在7至72岁之间的参与者（M = 26.60，SD = 17.45；26名女性）在下午有2小时的睡眠机会和同等时长的清醒时间之前，完成了一项学习和基线识别情绪记忆任务。延迟后也评估了识别准确性。我们发现，非周期性斜率在整个生命周期中呈U形轨迹：从童年到青年期斜率变平，此后变陡，这种效应在额叶区域最为明显。非周期性斜率的年龄相关差异也解释了情绪记忆巩固中的个体差异，与睡眠后但非清醒后负面刺激更强的巩固相关的斜率随年龄的扁平化程度较低。最后，独立于非周期性活动，NREM振荡活动的年龄相关差异预测了情绪记忆巩固。这些发现表明，基于睡眠的情绪记忆巩固效率受到非周期性神经活动和NREM振荡活动中与年龄相关差异的调节，为贯穿整个生命周期的情绪记忆背后的神经生理机制提供了新的见解。
