Poster PresentationREM sleep provides a key window for emotional memory processing.Although respiration and emotional memory exhibit reciprocal regulation, how they interact during REM sleep remains unclear.This study investigates how respiration modulates brain activity during REM sleep and how such lungbrain coupling further influences emotional learning during REM sleep.Thirty-three participants completed a pre-sleep encoding task, REM target memory reactivation (TMR), and post-TMR tests.During the pre-sleep task, participants performed word-sound-picture pairing and sequence encoding tasks, with positive real words followed by pseudowords to establish an emotional valence context for pseudowords.During late-night REM sleep, TMR was applied to reactivate the positive sequences alongside novel pseudowords to induce emotional valence learning of pseudowords during sleep.Upon awakening, participants completed affective judgment tasks with pseudowords to assess the emotional learning effects, and how respiratory effects on TMR-induced REM emotional learning were examined via respiratory-EEG cross-frequency coupling.Results showed that participants exhibited positive learning during REM sleep, with significant implicit preferences toward positive pseudowords relative to neutral pseudowords(t=-3.167,p<0.01,Cohens d=-0.551).Additionally, drift-diffusion analyses revealed that positive pseudowords exhibited faster information accumulation rates(vNeu -vPos, Meandiff=-0.612,95%HDI -0.930, -0.276).Preliminary respiratory analyses revealed that inhalation elicits stronger brain activity than exhalation.Moreover, the respiratory phase exerted a significant modulatory effect on brain activity during REM sleep, particularly in the delta and theta bands (MI: F(3,42.6)=16.8,p<0.001).Thus, emotional memory learning occurs during REM sleep, where the respiratory phase modulates brain activity.Future analyses will explore body-brain mechanisms underlying the learning.
Li et al. (2026) studied this question.