A study on the relationship between psychological resilience, vagal tone, and social adaptation: A non-pharmacological treatment perspective based on left-behind children

This study aims to explore the relationship between psychological resilience, vagal tone (heart rate variability [HRV]), and social adaptation, with a focus on the mediating role of HRV in the impact of psychological resilience on social adaptation. It also seeks to provide theoretical support for mental health interventions for left-behind children from a non-pharmacological perspective. This study employed a cross-sectional design with cluster sampling to select 2 middle schools in the urban-rural fringe of Zaoqiang County, Hebei Province, with a total of 312 left-behind children as the research subjects. Of these, 156 children were in the high-resilience group and 156 were in the low resilience group. The Youth Resilience Scale and the Adolescent Social Adaptation Scale were used to assess resilience and social adaptation. HRV was measured using portable equipment to assess high-frequency power (HF) and pNN50. Data analysis included descriptive statistics, analysis of covariance (ANCOVA), Pearson correlation analysis, mediation effect testing, logistic regression, and multiple linear regression. The high-resilience group showed significantly better HRV (HF and pNN50) and social adaptation compared to the low resilience group (all P <.001). Psychological resilience was significantly positively correlated with HRV (R = 0.59-0.81) and social adaptation (R = 0.95). Mediation analysis revealed that both HRV-HF and HRV-pNN50 partially mediated the relationship between psychological resilience and social adaptation (indirect effects = 0.25, 95% CI did not include 0). Logistic and multiple regression analyses further confirmed that psychological resilience (B = 2.12, P <.001) and HRV-pNN50 (B = 0.14, P = .005) were important positive predictors of social adaptation. Psychological resilience is significantly associated with better social adaptation among left-behind children, and this relationship may be partially explained by vagal tone (HRV), which plays a potential mediating role. This study provides physiological support for HRV-based non-pharmacological psychological interventions and holds significant theoretical and practical value.