Threat experiences and adolescent non-suicidal self-injury: Role of negative cognitive processing bias and vagal regulation

Abstract

Non-suicidal self-injury (NSSI) is of increased prevalence in adolescents. Threat experiences early in life including childhood abuse and bullying victimization, are considered precursors of non-suicidal self-injury, however, the underlying mechanism remains underexplored. Therefore, the present study sought to investigate the relation between threat experiences and adolescents' non-suicidal self-injury, and the mediating role of negative cognitive processing bias and moderating role of vagal regulation in this link. The Childhood Trauma Questionnaire Short Form, Delaware Bullying Victimization Scale, Negative Cognitive Processing Bias Questionnaire, and Non-Suicidal Self-Injury Questionnaire were administered to 210 junior school students (Mage = 12.92 years; 50.0 % female), who underwent a stress task (public speech task) during which data of vagal regulation indexed by respiratory sinus arrhythmia (RSA) suppression were collected. Results showed that threat experiences were positively related to non-suicidal self-injury, and negative cognitive processing bias mediated this link. Moreover, RSA suppression in response to stress served as a moderator, such that a positive association between threat experiences and negative cognitive processing bias was only evident among adolescents with higher RSA suppression but not those with lower RSA suppression. These findings suggest that negative cognitive processing bias is a potential mechanism linking threat experiences with adolescent non-suicidal self-injury, and adolescents with higher vagal suppression are more vulnerable to threat experiences and exhibit greater negative cognitive processing bias.