Neuroscience and Behavior Program, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA.
Institute for Applied Life Sciences, University of Massachusetts Amherst, Amherst, Massachusetts 01003, USA.
Learn Mem. 2023 Sep 28;30(9):237-244. doi: 10.1101/lm.053685.122. Print 2023 Sep.
Emotional memories are processed during sleep; however, the specific mechanisms are unclear. Understanding such mechanisms may provide critical insight into preventing and treating mood disorders. Consolidation of neutral memories is associated with the coupling of NREM sleep slow oscillations (SOs) and sleep spindles (SPs). Whether SO-SP coupling is likewise involved in emotional memory processing is unknown. Furthermore, there is an age-related emotional valence bias such that sleep consolidates and preserves reactivity to negative but not positive emotional memories in young adults and positive but not negative emotional memories in older adults. If SO-SP coupling contributes to the effect of sleep on emotional memory, then it may selectively support negative memory in young adults and positive memory in older adults. To address these questions, we examined whether emotional memory recognition and overnight change in emotional reactivity were associated with the strength of SO-SP coupling in young ( = 22) and older ( = 32) adults. In younger adults, coupling strength predicted negative but not positive emotional memory performance after sleep. In contrast, coupling strength predicted positive but not negative emotional memory performance after sleep in older adults. Coupling strength was not associated with emotional reactivity in either age group. Our findings suggest that SO-SP coupling may play a mechanistic role in sleep-dependent consolidation of emotional memories.
情绪记忆在睡眠中进行加工；然而，具体的机制尚不清楚。了解这些机制可能为预防和治疗情绪障碍提供重要的见解。中性记忆的巩固与非快速眼动 (NREM) 睡眠慢波 (SOs) 和睡眠纺锤波 (SPs) 的耦合有关。SO-SP 耦合是否同样参与情绪记忆处理尚不清楚。此外，还存在与年龄相关的情绪效价偏差，即睡眠巩固和保留对年轻成年人的负性但不是正性情绪记忆的反应性，以及对老年成年人的正性但不是负性情绪记忆的反应性。如果 SO-SP 耦合有助于睡眠对情绪记忆的影响，那么它可能会选择性地支持年轻成年人的负性记忆和老年成年人的正性记忆。为了解决这些问题，我们研究了情绪记忆识别和夜间情绪反应性的变化是否与年轻（n = 22）和老年（n = 32）成年人 SO-SP 耦合的强度有关。在年轻成年人中，睡眠后 SO-SP 耦合强度预测了负性但不是正性情绪记忆表现。相比之下，在老年成年人中，睡眠后 SO-SP 耦合强度预测了正性但不是负性情绪记忆表现。在两个年龄组中，SO-SP 耦合强度都与情绪反应性无关。我们的研究结果表明，SO-SP 耦合可能在情绪记忆的睡眠依赖性巩固中发挥机制作用。
