24 sessions of sequential prefrontal alpha-theta neurofeedback training over 8 weeks (3 sessions/week, 30 min/session). Each session: 5 min alpha feedback (8-12 hertz [Hz]) followed by 25 min theta feedback (4-7 Hz) at Fp1/Fp2, delivered via ocean wave and birdsong audio while eyes closed. Device: Power Nap (Neuro21, Korea).

Participants continued usual daily activities for 8 weeks without any intervention. Pre- and post-test assessments (EEG and self-report measures) were conducted.

Operant conditioning-based neurofeedback: 5 min alpha (8-12 Hz) + 25 min theta (4-7 Hz) at prefrontal sites Fp1/Fp2 per session; 24 sessions over 8 weeks supervised by a certified practitioner. Audio feedback (ocean waves for alpha, birdsong for theta) delivered via Power Nap device (Neuro21, Korea) while participants remained eyes-closed and seated.

Total score on the Alcohol Abstinence Self-Efficacy Scale (AASE; Korean adaptation), a 20-item scale with four subscales (Negative Affect, Social/Positive Emotions, Physical and Other Concerns, Withdrawal and Urges), each rated 0-4; higher scores indicate greater confidence in maintaining abstinence.

Total score on the Mindfulness Scale (20 items, 4 subscales: Decentered Attention, Nonjudgmental Acceptance, Present-Moment Awareness, Attentional Focus), rated 1-5 (reverse-scored); higher scores indicate greater mindfulness.