Effectiveness of Rain Sound Music as a Relaxation Stimulus on Parasympathetic Nervous System Activity Based on Heart Rate and REM Sleep Stage

This is the authors' abstract. We don't add key points for this paper.

Stress may arise due to internal and external stressors. Persistent stress can induce psychological pressure and may progress to a state of mental exhaustion (burnout). In addition, stress can contribute to sleep disturbances, potentially exacerbating anxiety and depression, thereby creating a continuous cycle. This study aimed to analyze parasympathetic nervous system activation through the vagal system based on changes in heart rate and the stability of the REM sleep phase during exposure to rain sound music while sleeping. This study employed a quantitative approach with a quasi-experimental design using a one-group pretest-posttest design involving 20 research subjects. The intervention consisted of exposure to rain sound music delivered through the YouTube platform, while heart rate and REM sleep phase measurements were obtained using a digital smartwatch. The study was conducted over eight days, consisting of four days without rain sound music intervention and four days with rain sound music intervention. The paired t-test revealed a significant decrease in mean heart rate from 57.50 ± 7.85 bpm to 54.95 ± 7.76 bpm (p = 0.009), while the Wilcoxon signed-rank test indicated a significant increase in the mean REM sleep duration from 64.40 ± 23.72 min to 72.55 ± 22.97 min (p = 0.040). These findings indicate that rain sound music intervention may provide a relaxation effect through enhanced parasympathetic activity, characterized by reduced heart rate and increased REM sleep duration. Future studies are recommended to incorporate Heart Rate Variability (HRV) measurements and electrocardiography (ECG)-based smartwatch features to obtain a more comprehensive assessment of autonomic nervous system activity.