Effect of HRV biofeedback on cognition in neurological conditions: Systematic review

Heart rate variability (HRV) biofeedback is a psychophysiological intervention grounded in autonomic regulation theory, with increasing evidence linking vagal control to higher-order cognitive processes, particularly executive functioning. Adults with neurological conditions frequently exhibit autonomic dysregulation alongside cognitive impairment, suggesting HRV biofeedback as a potentially valuable adjunct in neurorehabilitation. This systematic review aimed to critically examine the effects of HRV biofeedback on cognitive outcomes in adults with neurological disorders. A systematic literature search was conducted in PubMed, Scopus, and Web of Science. Randomized controlled trials and quasi-experimental studies evaluating HRV biofeedback as the primary intervention with cognitive outcomes in adult neurological populations were included. Methodological quality was assessed using the PEDro and JBI checklists. Risk of bias was evaluated using the Cochrane Risk of Bias 2.0 and ROBINS-I tools. Six studies involving 263 adults with stroke, traumatic brain injury, and Alzheimer’s disease met the inclusion criteria. Across studies, HRV biofeedback was associated with improvement in executive function, attention, social cognition, and global cognitive performance, measured using validated instruments including MMSE, MoCA, BRIEF-A, and TASIT. Overall study quality was rated as good, with low to moderate risk of bias; however, heterogeneity in intervention protocols and cognitive outcomes measures limited quantitative synthesis. Current evidence suggests that HRV biofeedback may enhance cognitive functioning in adults with neurological disorders by supporting autonomic-prefrontal integration. While findings are promising, further large-scale, methodologically robust trials are required to confirm efficacy and inform clinical application.