EEG Signatures and Effects of Mindfulness Approaches in Adolescents With Nonsuicidal Self-Injury.

Nonsuicidal self-injury (NSSI) is a recurring behavior most prevalent among adolescents in which one intentionally harms one's tissues and organs without the intent of death, which has a complex pathophysiology and lacks established interventions. As NSSI has been linked to deficits in cognitive control, mindfulness training that enhances this process may be beneficial. In this study, using electroencephalography (EEG), we examined the neural mechanisms underpinning NSSI and the impact of mindfulness interventions by analyzing brain activity before, during, and after a 10-min brief breath-focused meditation session in adolescents with NSSI. We demonstrate that adolescent NSSI patients show a lower correct rejection rate and sensitivity in an emotional go/no-go task that reflects deficits in cognitive control compared to healthy controls, along with reduced P3 amplitude and theta power. A brief deep breath meditation intervention, but not natural breath meditation intervention, restored the decreased no-go theta power in NSSI patients. Analysis of microstates and neural network of resting-state EEG during meditation showed that properties of microstate D reflecting activation of the attention network differed between intervention strategies and predicted NSSI remission at 1-month follow-up. These findings provided evidence for inhibition deficits in adolescents with NSSI, suggest a role of P3 and theta power in identifying NSSI, support the therapeutic benefits of brief meditation, and reveal novel electrophysiological markers of NSSI diagnosis, intervention effects, and outcomes.