Is non-suicidal self-injury an "addiction"? A comparison of craving in substance use and non-suicidal self-injury.

There is debate among researchers regarding the most appropriate conceptual model of non-suicidal self-injury (NSSI). Some argue that NSSI is best viewed within an addictions framework. Because craving of substances is a key concept in the addictions literature, we sought to compare the nature of craving in NSSI and substance use. Measures of NSSI, substance use, and craving were administered to a sample of adolescents (n=58) receiving psychiatric treatment. It was found that total craving scores were significantly lower for NSSI than for substances. Item-level analyses suggested that substances are craved in a variety of contexts, whereas NSSI is typically craved in the context of negative emotions. The pattern of results remained the same when analyses were limited to patients who engaged in both NSSI and substance use. Thus, findings appear to be due to differences in the nature of the behaviors themselves rather than to individual differences between those who engage in NSSI or use substances. We conclude that, while both behaviors have powerful reinforcement contingencies, NSSI appears to be almost exclusively maintained by negative reinforcement (e.g., the reduction of aversive emotions). Findings are more consistent with emotion regulation than addiction models of NSSI.