Psychophysiological and neural support for enhanced emotional reactivity in adolescent females with nonsuicidal self-injury

Abstract Background Nonsuicidal self-injury (NSSI) is prevalent in adolescent populations worldwide. Emotion dysregulation is believed to contribute to NSSI, but underlying mechanisms are less known. Here, we combine psychophysiological and neural data with subjective self-report in close temporal proximity to examine the mechanisms underlying emotion processing in adolescents with NSSI relative to control adolescents without a psychiatric diagnosis. Methods Thirty female adolescents with NSSI and thirty age-matched female controls were included in this case-control study. Participants were presented with negative affective pictures during a functional magnetic resonance imaging (fMRI) scan. In a separate facial electromyography (EMG) session, the same participants were shown positive and negative affective images and also provided ratings of valence and arousal. Results Participants with NSSI responded to affective images with greater positive (e.g. zygomatic) and greater negative (e.g. corrugator) reactivity. We found no differences in self-reported affect in response to the images. Analyses of the negative picture-viewing fMRI data showed a significant positive correlation between anterior insula response and the averaged EMG magnitude in NSSI, but not in controls. Conclusions Adolescents with NSSI show enhanced emotional reactivity that is associated with anterior insula responding, but no abnormalities in self-reported affect. This discrepancy between self-report and objective measures of emotional reactivity potentially indicates a suppression of the emotional reaction in adolescents with NSSI. Moreover, the current data suggest potential targets for novel therapeutic approaches that can be combined with existing clinical treatment, such as real-time EMG-based biofeedback focusing on emotional awareness, labeling, and expressing emotional experiences.