Non-suicidal self-injury (NSSI) is the deliberate, direct destruction or alteration of body tissue without conscious suicidal intent (Pattison & Kahan, 1983; Favazza, 1998). Recent reviews on NSSI (Suyemoto, 1998; Klonsky, 2007) have suggested multiple functions of NSSI, with affect-regulation models having the most support. However, no research has directly tested whether NSSI regulates affect in more than one way. It is possible that there are multiple pathways through which affect may be regulated.
Two recent models of NSSI incorporate affect regulation as a function of NSSI. Nock and Prinstein (2004) recently proposed a two-dimensional functional model of NSSI. These authors argued that there are four primary functions of NSSI that range along two dimensions, reinforcement and contingencies. The second recently proposed theoretical model, the Experiential Avoidance Model (EAM; Chapman, Gratz, & Brown, 2006), argues that NSSI is maintained by negative reinforcement in the form of escape from, or avoidance of, unwanted emotional experiences.
The first goal of the present study was to simultaneously examine components of two affect-regulation models of NSSI. The second goal of the present study was to investigate the unique and joint contribution of worry and rumination in a model of NSSI. Participants were 95 undergraduate students from the Kent State University General Psychology Subject Pool who reported engaging in at least one NSSI act during their lives. Following informed consent, participants completed measures of worry, rumination, functions of NSSI, avoidance, and NSSI behaviors. Path analysis and structural equation modeling were used to investigate affect-regulation functions of NSSI and avoidance as mediators of the relationship between brooding, worry, and NSSI. Results suggested the initial hypothesized model and a post-hoc model provided the best fit to the data, although there was no support for mediation. Results generally lend stronger support to the functional model than the experiential avoidance model. Further, results suggest that brooding, but not worry, may better serve as a variable of heightened affect in affect regulation models of NSSI.