Music in the loop: a systematic review of current neurofeedback methodologies using music

Alexandre Sayal ^1,2,3,4* Bruno Direito ^1,4,5 Teresa Sousa ^1,4,6 Neomi Singer ⁷ Miguel Castelo-Branco ^1,4,6,8

• ¹ Coimbra Institute for Biomedical Imaging and Translational Research (CIBIT), Coimbra, Portugal
• ² Siemens Healthineers (Portugal), Lisbon, Portugal
• ³ Faculty of Sciences and Technology, University of Coimbra, Coimbra, Coimbra, Portugal
• ⁴ Intelligent Systems Associate Laboratory (LASI), Coimbra, Portugal
• ⁵ Center of Informatics and Systems, University of Coimbra, Coimbra, Coimbra, Portugal
• ⁶ Faculty of Medicine, University of Coimbra, Coimbra, Coimbra, Portugal
• ⁷ Sagol Brain Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Tel Aviv, Israel
• ⁸ Institute of Nuclear Sciences Applied to Health, University of Coimbra, Coimbra, Coimbra, Portugal

Music, a universal element in human societies, possesses a profound ability to evoke emotions and influence mood. This systematic review explores the utilization of music to allow self-control of brain activity and its implications in clinical neuroscience. Focusing on music-based neurofeedback studies, it explores methodological aspects and findings to propose future directions. Three key questions are addressed: the rationale behind using music as a stimulus, its integration into the feedback loop, and the outcomes of such interventions. While studies emphasize the emotional link between music and brain activity, mechanistic explanations are lacking. Additionally, there is no consensus on the imaging or behavioral measures of neurofeedback success. The review suggests considering whole-brain neural correlates of music stimuli and their interaction with target brain networks and reward mechanisms when designing music-neurofeedback studies. Ultimately, this review aims to serve as a valuable resource for researchers, facilitating a deeper understanding of music's role in neurofeedback and guiding future investigations.