Abstract
Abstract: Neurological and psychiatric disorders frequently present with treatment-refractory symptoms, creating a significant demand for effective non-pharmacological interventions. Biofeedback and neurofeedback have emerged as prominent modalities, yet their utility remains contentious due to a landscape of varied protocols and conflicting research findings. This review aims to provide a critical, evidence-based synthesis of their application and efficacy to guide clinical decision-making. The methodology involved a search of high-level evidence, systematic reviews, and meta-analyses, from the PubMed/MEDLINE and Cochrane Library prioritizing publications from the last 15 years. The results indicate a robust evidence base for peripheral biofeedback in migraine management and for sensorimotor rhythm and slow cortical potential (SCP) neurofeedback in refractory epilepsy, with the latter demonstrating remarkable long-term durability. Heart Rate Variability (HRV) biofeedback shows strong efficacy for anxiety and Post-Traumatic Stress Disorder (PTSD). In contrast, the evidence for theta/beta neurofeedback in Attention-Deficit/Hyperactivity Disorder (ADHD) is highly contested due to fundamental methodological issues with rater blinding, and frontal alpha asymmetry neurofeedback for Major Depressive Disorder (MDD) is undermined by a significant replication crisis concerning its foundational biomarker. It is concluded that while biofeedback and neurofeedback provide solid, evidence-based interventions for select conditions, the broader field is hampered by a lack of protocol standardization and significant methodological challenges. The future of these therapies is contingent on a paradigm shift towards a precision-medicine model, leveraging rigorous research to identify predictive biomarkers and determine for whom these therapies are most effective