The Impact of Beta-band Transcranial Alternating Current Stimulation (tACS) on Impulse Inhibition in Adolescents With Non-suicidal Self-injury

The Impact of Beta-band Transcranial Alternating Current Stimulation (tACS) on Impulse Inhibition in Adolescents With Non-suicidal Self-injury

This clinical trial aims to determine whether beta-band transcranial alternating current stimulation (tACS) can improve impulse inhibition in adolescents with non-suicidal self-injury (NSSI) and to evaluate its safety. The primary questions it seeks to answer are:

• Can beta-band tACS significantly reduce the frequency of self-injury and scores on impulsivity scales in adolescents with NSSI?
• What discomfort or medical issues may participants experience during tACS intervention?

Researchers will compare beta-band tACS with sham stimulation (a procedure that mimics the real stimulation without delivering effective current) to verify its efficacy.

Participants will:

• Receive two sessions of either tACS or sham stimulation daily, spaced 4 hours apart, for 7 consecutive days (14 sessions in total).
• Undergo scale assessments, behavioral tasks, and eye-tracking tests before and after the intervention.
• Record any self-injury episodes and adverse reactions, with continuous monitoring and psychological support provided by a professional team.

Inclusion Criteria:

• 1) Meet the proposed diagnostic criteria for non-suicidal self-injury (NSSI) in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), with ≥5 documented self-injury episodes and at least one incident within the past month as assessed by the Adolescent Non-Suicidal Self-Injury Assessment Questionnaire (ANSAQ); 2) Aged 12-18 years; 3) Right-handed; 4) Possess formal education experience sufficient to comprehend experimental protocols; 5) Normal or corrected-to-normal binocular visual acuity; 6) Voluntarily participate with legal guardians providing written informed consent.

Exclusion Criteria:

• 1) Montreal Cognitive Assessment (MoCA) score < 26; 2) History of suicide attempt(s); 3) Medical history of epilepsy, brain surgery, intracranial tumors, metal implants in the skull, or clinically significant head trauma; 4) History of substance use disorder, brain injury, severe somatic diseases, psychiatric disorders, or comorbid DSM-5 psychiatric conditions; 5) Prior receipt of transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), or repetitive transcranial magnetic stimulation (rTMS) within the past 3 months