Altered parasympathetic activity during sleep and emotionally arousing wakefulness in frequent nightmare recallers
European Archives of Psychiatry and Clinical Neuroscience March 2, 2023 Vivien Tomacsek, Borbála Blaskovich, Anna Király et al. 8 citations
People who frequently recall nightmares show signs of dysfunctional parasympathetic regulation during sleep and in response to emotional distress. Compared to healthy controls, nightmare recallers had higher heart rates during sleep segments (pre-REM, REM, post-REM, and slow wave sleep), but not during resting wakefulness, suggesting autonomic dysregulation specific to sleep. Heart rate variability did not differ significantly between groups during sleep, implying that parasympathetic changes may depend on nightmare severity. During an emotion-evoking picture-rating task designed to model nightmare experiences, nightmare recallers showed increased heart rate and reduced heart rate variability, indicating disrupted emotion regulation under acute distress. These findings point to both trait-like autonomic changes during sleep and state-like responses to emotional challenges.