# The impact of internet addiction on non-suicidal self-injury among adolescents: a moderated chain mediation model

## TL;DR

This study explores how internet addiction increases non-suicidal self-injury in adolescents through social anxiety and depression, with emotional regulation playing a key role.

## Contribution

The study introduces a moderated chain mediation model linking internet addiction to self-injury via social anxiety and depression, moderated by trait meta-mood.

## Key findings

- Internet addiction is positively correlated with non-suicidal self-injury in adolescents.
- Social anxiety and depression form a chain mediation pathway explaining 26% of the effect.
- High trait meta-mood strengthens the mediation pathway between internet addiction and self-injury.

## Abstract

Adolescence is a critical period for personality development and a high-risk phase for psychological conflicts. With the increasing severity of mental health issues among adolescents, this study investigates the mechanisms underlying the relationship between internet addiction (IA) and non-suicidal self-injury (NSSI) in adolescents, focusing on the mediating roles of social anxiety and depression and the moderating effect of trait meta-mood. The aim of this study is to uncover the psychological motivations behind NSSI and provide a theoretical basis for identifying potential risks to adolescent mental health, ultimately contributing to the prevention of psychological crises.

A total of 692 high school students from Heilongjiang Province, China, completed the Internet Addiction Test (IAT), the Deliberate Self-Harm Inventory (DSHI), the Liebowitz Social Anxiety Scale (LSAS), the Beck Depression Inventory-II (BDI-II), and the Trait Meta-Mood Scale (TMMS). Structural equation modeling was used to examine the mediating and moderating effects among the variables.

(1) A significant positive correlation was found between internet addiction and NSSI (r = 0.278, p < 0.01). (2) Social anxiety (indirect effect = 0.042) and depression (indirect effect = 0.019) formed a chain mediation pathway, explaining 26% of the total effect. (3) Trait meta-mood moderated the first half of the mediation pathway (R2 = 0.161, p < 0.001), with the mediating effect of internet addiction being stronger at high levels of trait meta-mood (0.08) than at low levels (0.036).

Internet addiction exacerbates the risk of NSSI in adolescents through a progressive pathway of “social anxiety → depression.” trait meta-mood plays a crucial role in moderating this process, highlighting the importance of emotional regulation in mitigating the adverse effects of internet addiction on adolescent mental health.