Why Do People Hurt Themselves?

The past two decades have seen a tremendous increase in research on nonsuicidal self-injury (NSSI), the act of intentionally damaging one’s own tissue without intent to die. This body of research indicated that NSSI may serve an emotion regulation function for those who engage in it, both in terms of reducing negative emotions, and as a means to achieve positive emotional states, such as “fun” or “excitement.” Succeeding in altering one’s emotional state by engaging in NSSI might therefore reinforce this self-injurious behavior. This chapter reviews theoretical and empirical work on the motivational forces shown to promote NSSI in order evaluate whether this research supports the notion of reinforcement-based motivation for NSSI. Particular attention in the chapter is given to how developmentally relevant correlates of reward and motivation (e.g., sensation seeking) might increase NSSI risk among adolescents. The chapter concludes by offering insights and recommendations for future research.