DYNAMICS OF SLEEP ARCHITECTURE RESTORATION AND AUTONOMIC RESPONSES AFTER NIGHTLY WAR-RELATED STRESS
Main Article Content
Abstract
Methods. Data from 39 individual sleep cycles recorded over five consecutive nights were analyzed (Baseline – control night, Night 0 – night of missile attack, Night 1-3 – recovery period). Sleep architecture and heart rate indicators were assessed using wearable data. Additionally, an exploratory single-case observation with parallel EEG (Hypnodyne ZMax) recording was performed. Statistical analysis included RM-ANOVA, Bonferroni post hoc test, Pearson correlation, and event-based metrics (PPV, F1-score, Cohen’s κ).
Originality. The study provides the quantitative evidence of dissociation between REM sleep macro- and microstructure under real war-related stress conditions. It offers a novel approach for remote sleep assessment using heart rate dynamics as a proxy for detecting microarousals.
Results. The sleep macrostructure remained relatively stable despite acute stress, whereas REM sleep showed pronounced fragmentation. Detection of microarousals based on heart rate demonstrated consistency with EEG and greater informational value of autonomic responses under stress.
Conclusions. Sleep parameter recovery after acute stress follows a delayed, gradual pattern. Although consumer-grade wearable devices have limitations in estimating absolute sleep parameters, they can be used to monitor stress-related dynamics and indirectly assess REM-fragmentation.
Keywords: sleep neurophysiology; REM sleep; microarousals; sleep microstructure; autonomic regulation; wearable devices; post-stress recovery.
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