Negative emotional processing and decision-making inhibition deficits in adolescents with NSSI: a cross-sectional ERP study.

BACKGROUND: This study utilises ERP technology and the Iowa Gambling Task (IGT) to compare the behavioral and EEG characteristics of adolescents with non-suicidal self-injury (NSSI) and those with depression in response to negative emotional stimuli, with the aim of exploring the specific neural mechanisms underlying negative emotion processing and inhibitory control in adolescents with NSSI. METHODS: This study employed a cross-sectional between-groups design to compare 32 adolescents with NSSI and 34 adolescents with depression. All participants completed the emotion-face-based modified Iowa Gambling Task, whilst 64-channel EEG recordings were simultaneously acquired. The analysis focused on behavioral measures and ERP components such as the early posterior component and LPP. RESULTS: The net IGT score in the NSSI group was significantly lower than that in the Depression group [F(1, 64) = 9.06, p = 0.004], and the Group × Emotion interaction was significant (p = 0.030), with the largest difference observed under the anger condition. ERP analyses revealed a significant interaction: for the early posterior component (mean amplitude, 140-190 ms), the fear amplitude was significantly more negative (i.e., enhanced) in the Depression group, whilst there was no difference in the NSSI group; for the LPP (mean amplitude, 650-800 ms), the fear amplitude was significantly higher than the neutral amplitude in the NSSI group, whilst there was no difference in the Depression group. CONCLUSION: Adolescents with NSSI exhibit a 'differentiation between early and late stages' in the processing of negative emotions: in the early stage, there is insufficient differentiation in the encoding of negative emotions, whilst in the late stage, there is a marked attentional bias toward fearful faces; this provides electrophysiological evidence for NSSI.