The discussion centers on the functional role of REM sleep in emotional brain processing, highlighting its impact on mood disorders and affective brain function. Clinical evidence indicates that REM sleep suppresses central adrenergic neurotransmitters, which may help reduce emotional intensity by altering amygdala activity. The failure of this suppression in anxiety disorders is linked to persistent high-frequency EEG activity, contributing to hyperarousal. The peer-reviewed study by Els van der Helm et al. demonstrates that REM sleep is associated with decreased amygdala activity in response to prior emotional experiences, suggesting a mechanism for emotional regulation.
PREREQUISITESPsychologists, neuroscientists, sleep researchers, and mental health professionals interested in the intersection of sleep and emotional regulation.
Abstract said:Clinical evidence suggests a potentially causal interaction between sleep and affective brain function; nearly all mood disorders display co-occurring sleep abnormalities, commonly involving rapid-eye movement (REM) sleep [ [1] , [2] , [3] and [4] ]. Building on this clinical evidence, recent neurobiological frameworks have hypothesized a benefit of REM sleep in palliatively decreasing next-day brain reactivity to recent waking emotional experiences [ [5] and [6] ]. Specifically, the marked suppression of central adrenergic neurotransmitters during REM (commonly implicated in arousal and stress), coupled with activation in amygdala-hippocampal networks that encode salient events, is proposed to (re)process and depotentiate previous affective experiences, decreasing their emotional intensity [3]. In contrast, the failure of such adrenergic reduction during REM sleep has been described in anxiety disorders, indexed by persistent high-frequency electroencephalographic (EEG) activity (>30 Hz) [ [7] , [8] , [9] and [10] ]; a candidate factor contributing to hyperarousal and exaggerated amygdala reactivity [3 M.P. Walker and E. van der Helm, Overnight therapy? The role of sleep in emotional brain processing. Psychol. Bull., 135 (2009), pp. 731–748. Article | PDF (557 K) | | View Record in Scopus | | Full Text via CrossRef | Cited By in Scopus (30) [3] , [11] , [12] and [13] ]. Despite these neurobiological frameworks, and their predictions, the proposed benefit of REM sleep physiology in depotentiating neural and behavioral responsivity to prior emotional events remains unknown. Here, we demonstrate that REM sleep physiology is associated with an overnight dissipation of amygdala activity in response to previous emotional experiences, altering functional connectivity and reducing next-day subjective emotionality.