Background. Substance use disorders (SUD) are a significant health problem affecting executive function.Neurofeedback training (NFB) allows subjects to voluntarily modulate brain activity, aiming to modify cognitive processes. Studies measuring neuropsychological processes and music have found significant changes in attention, memory, and speech, supporting the notion that music enhances brain functioning. In this study, we measured cognitive processes (decision-making and attention) and emotional regulation aspects in a sample of Puerto Ricans with SUD, before and after participating in NFB-assisted training sessions with or without music. Method. Forty-six residency program patients were assigned to NFB, NFB+Music, or a control group. NFB protocol included reinforcement training of low beta sensorimotor rhythm (SMR) and theta and high beta inhibition at Cz. Results. Data suggest favorable changes in decision-making, attention, inhibitory control, and emotional regulation in the NFB groups. No differences were found in behavioral, self-reported, and EEG data between NFB and NFB+Music. Statistically significant changes on SMR amplitude were observed in both experimental groups. Self-reports underpin participants' relaxation states during NFB sessions. Discussion. NFB training with and without music effectively optimizes executive function; however, NFB+Music seems to have a precise effect on emotion regulation, particularly in emotion expression.