Self-referential processing in individuals with nonsuicidal self-injury: An fMRI study

Nonsuicidal self-injury (NSSI) is associated with considerable deficits in managing negative self-directed internal experiences. The present study explores the neurophysiological correlates of self-referential processing in individuals with NSSI. A total of 26 individuals with NSSI (>= 5 episodes of NSSI behavior in the past year, without suicide attempts) and 35 age-, sex-, education-, and intelligence quotient (IQ)-matched controls participated in this study. Participants underwent fMRI scanning as they performed a personal relevance rating task, which required them to evaluate the personal relevance of emotional words. As predicted, we found that individuals engaging in NSSI tended to rate negative adjectives as more relevant and positive adjectives as less relevant. An analysis of functional neuroimaging data showed that the NSSI group had increased activity relative to the control group in the inferior parietal lobe, inferior temporal gyrus, calcarine, insula, and thalamus in response to positive adjectives. The NSSI group also demonstrated greater activation in the calcarine and reduced activation in the inferior frontal gyrus in response to negative self-referential stimuli compared with the control group. In addition, increased right inferior parietal lobe activity during positive self-referential processing was correlated with reduced suicidal ideation in the NSSI group. Our study provides neural evidence for self-referential processing bias in individuals with NSSI and highlights the need for further research to clarify the pathophysiological features that are specific to NSSI.