Abstract

This study aimed to investigate the mediating effect of depression and the moderating effect of behavioral activation on the relationship between experiential avoidance and non-suicidal self-injury (NSSI) in early adulthood. Additionally, it explored the moderated mediation effect, wherein behavioral activation influences the indirect pathway through depression. The sample comprised 300 adults aged 19 to 34 who had engaged in NSSI within the past year or earlier. Participants completed assessments measuring experiential avoidance (AAQ-II), depression (PHQ-9), NSSI (FASM), and behavioral activation (K-BADS). The results indicated that experiential avoidance had a significant positive direct effect on NSSI, and the indirect pathway through depression was also statistically significant. Behavioral activation significantly moderated the indirect pathway, with higher levels of activation diminishing the impact of experiential avoidance on NSSI via depression. However, behavioral activation did not significantly moderate the direct pathway from experiential avoidance to NSSI. This study elucidated the roles of experiential avoidance and depression in NSSI among young adults and substantiated the potential therapeutic efficacy of behavioral activation for individuals engaging in NSSI, mediated by these factors. The findings suggest that behavioral activation may serve as a protective factor, interrupting the negative cycle among experiential avoidance, depression, and NSSI. These results are pivotal in enhancing the understanding of NSSI in early adulthood and in proposing effective intervention strategies. Limitations of the study and recommendations for future research are discussed.