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

Conditions studied

Depression Disorders, Non-suicidal Self-injury

About this study

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.

Interventions

• Device: Beta-frequency transcranial alternating current stimulation — Active beta-frequency transcranial alternating current stimulation: 20 Hz tACS delivered through a 4×1-ring high-definition electrode montage centered on left DLPFC (F3), 2 mA peak-to-peak, 100 % intensity, gradually ramped up over 30 s, maintained for 20 min, then ramped down over 30 s; two sessions per day with at least 4 h between sessions, repeated for 7 consecutive days (14 total sessions).
• Device: sham beta-frequency transcranial alternating current stimulation — Sham transcranial alternating current stimulation: identical 4×1-ring high-definition electrode montage centered on left DLPFC (F3), 2 mA peak-to-peak current ramped up over 30 s and immediately ramped down to 0 mA, followed by 19.5 min of no stimulation to match the 20-min session duration of active tACS; delivered twice daily (≥4 h apart) for 7 consecutive days (14 total sessions).

Primary outcomes

• Adolescent Non-suicidal Self-injury Assessment Questionnaire (ANSAQ) reduction in the frequency of self-injury (Once at baseline (pre-treatment) and once at the end of treatment on Day 8.)
• UPPS-P Impulsive Behavior Scale (UPPS-P) (Once at baseline (pre-treatment) and once at the end of treatment on Day 8.)
• Brief Barratt Impulsiveness Scale (BBIS) (Once at baseline (pre-treatment) and once at the end of treatment on Day 8.)
• Eye movement index-fixation time (Once at baseline (pre-treatment) and once at the end of treatment on Day 8.)
• Eye movement index-fixation counts (Once at baseline (pre-treatment) and once at the end of treatment on Day 8.)
• Balloon Analog Risk Task-Total number of Balloon explosions (Once at baseline (pre-treatment) and once at the end of treatment on Day 8.)

Eligibility information

Study locations

• School of Mental Health and Psychological Sciences, Anhui Medical University, Hefei, Anhui China