The functions of nonsuicidal self-injury: support for cognitive-affective regulation and opponent processes from a novel psychophysiological paradigm.

Although research on the reasons for engaging in nonsuicidal self-injury (NSSI) has increased dramatically in the last few years, there are still many aspects of this pernicious behavior that are not well understood. The purpose of this study was to address these gaps in the literature, with a particular focus on investigating whether NSSI (a) regulates affective valence in addition to affective arousal and (b) serves a cognitive regulation function in addition to an affect regulation function. To elucidate these issues, the present study utilized a sample of 112 participants (33 controls, 39 no pain controls, 16 NSSI individuals, and 24 controls matching the affect dysregulation levels of the NSSI group), employed psychophysiological measures of affective valence (startle-alone reactivity) and quality of information processing (prepulse inhibition), and used experimental methods involving an NSSI-proxy to model the NSSI process. Results largely were consistent with predictions, supporting the hypotheses that NSSI serves to regulate cognitive processing and affective valence. On this latter point, however, the control groups also showed a decrease in negative affective valence after the NSSI-proxy. This unexpected finding is consistent with the hypothesis that opponent processes may contribute to the development of self-injurious behaviors (Joiner, 2005). Overall, the present study represents an important extension of previous laboratory NSSI studies and provides a fertile foundation for future studies aimed at understanding why people engage in NSSI.