Efficacy of Triple-daily 15mA tACS on Adolescent NSSI

Efficacy of Triple-daily 15mA Transcranial Alternating Current Stimulation on Adolescent Non-suicidal Self-injury (NSSI): a Double-blind, Randomized, Sham-controlled Trial

In order to assess the clinical efficacy of triple-daily 15mA-tACS stimulation by comparing the effects of active and sham tACS interventions on driving improvements in adolescent Nonsuicidal Self-Injury(NSSI), participants will be randomly assigned to either the active or sham tACS group. This trial consists of a 2-week intensified intervention phase (40 sessions), followed by a 4-week observation period. The key hypothesis is that triple-daily 15mA-tACS stimulation will enhance clinical recovery compared to sham stimulation.

Recognizing the clinical shortcomings of traditional methods for adolescent NSSI, study objective is to establish evidence supporting the efficacy of a triple-daily 15mA-tACS stimulation regimen targeting the forehead and both mastoids. This intervention will be administered five days a week over a four-week treatment period, with the aim of eliciting substantial clinical improvements in adolescent NSSI compared to a sham intervention. On the first day of the intervention, participants will receive a tACS session, followed by triple-daily tACS sessions administered for 13 consecutive days. Following the completion of treatment, participants will undergo follow-up observations every 7 days for 4 weeks. EEG and ECG recordings will be obtained at baseline, on day 1 after the first session, at the end of the 2-week intervention period (after 40 sessions), and at the 6-week follow-up. Throughout the sessions, all evaluations will be conducted under standardized conditions.

Inclusion Criteria:

• Diagnosis of NSSI based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria section 3 diagnostic criteria.
• Five or more NSSI episodes in the past year and at least one NSSI episode in the past month.
• Age between 12 and 21 years.
• Informed consent from parents or legal guardians.
• Informed consent from participants aged 15 years and above.

Exclusion Criteria:

• Current or history of organic brain disorders or neurological disorders.
• Elevated or imminent suicidal risk, as assessed by clinicians during routine screening.
• Previous or current exposure to electroconvulsive therapy (ECT), modified ECT, TMS, transcranial direct current stimulation (tDCS), tACS, or other neurostimulation treatments.
• Presence of cochlear implants, cardiac pacemakers, implanted devices, or metal in the brain.
• Previous or current use of psychotropic medication.
• Pregnancy or lactation.
• Participation in another concurrent clinical trial.
• Refusal to provide informed consent to participate in the trial.
• Other circumstances deemed unsuitable for participation by researchers.