Preferential consolidation of emotional reactivity during sleep: A systematic review and meta-analysis.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of 24 controlled experimental human studies.
PubMed 36268469 · doi:10.3389/fnbeh.2022.976047
What was done
Authors conducted a systematic review and meta-analysis across PubMed, PsycINFO, PsycARTICLES, Web of Science, and Cochrane Library (January 2006–June 2021). The review synthesized 24 human studies examining pre- to post-interval changes in subjective (self-report) and objective (psychophysiological) reactivity to positively, negatively, or neutrally valenced stimuli across a period of sleep versus matched wakefulness. Analyses utilized random-effects modeling and tested moderators including sleep deprivation, naps, and REM sleep parameters.
What was found
Neither sleep nor wakefulness significantly altered psychophysiological measures of reactivity to negative or neutral stimuli. In contrast, self-reported arousal ratings for negative stimuli significantly increased following sleep but not wakefulness (no specific effect sizes or p-values reported in abstract). Subgroup analyses found that sleep-deprived individuals reacted more negatively to positive stimuli than sleeping or waking controls; nap-exposed participants rated negative pictures less negatively than full-night sleepers or wake controls; and participants lacking substantial REM sleep demonstrated attenuated reactivity to neutral stimuli.
Why it matters
This synthesis clarifies conflicting literature by identifying a divergence between subjective and objective emotional processing: sleep selectively preserves or enhances subjective arousal to negative stimuli without broadly altering psychophysiological reactivity, with effects modulated by sleep architecture.
Limits
The abstract does not provide exact numerical effect sizes, test statistics, confidence intervals, or total participant sample sizes. Findings are limited by substantial methodological variations across included studies, inconsistent reporting of REM sleep parameters, and a lack of concurrent objective and subjective measurements within individual trials.