The effects of self-injury on acute negative arousal: A laboratory simulation

Research suggests that performance of non-suicidal self-injury (NSSI) is associated with the reduction of high-arousal negative affect. The present study examined this phenomenon in a laboratory setting. Individuals with a history of NSSI ( n = 39) and non-NSSI controls ( n = 33) underwent an anger induction, and were randomized to self-administer either a high level of electric shock, or a mild shock (control condition) to their upper arm. Consistent with previous research, injurers displayed greater pain analgesia than controls. Contrary to expectations, high shock did not result in enhanced arousal reduction for injurers. However, the high shock led to greater arousal reduction for injurers than controls. Notably, in the high shock condition, higher levels of electrical stimulation (i.e., voltage administered) predicted greater reductions in negative arousal, whereas higher subjective ratings of pain predicted smaller reductions in negative arousal. This pattern suggests that more intense self-inflicted pain facilitates reduction of negative arousal provided the subjective experience of pain is not too aversive. Findings help clarify emotion-regulation models of NSSI.