Beyond exercise: a scoping review of heart rate variability in cognitive and emotional paradigms following adult concussion.

BACKGROUND

Concussions often result in psychophysiological symptoms that reflect disruptions in brain-body systems, yet objective biomarkers remain limited. Heart rate variability (HRV) has emerged as a promising biomarker of autonomic adaptability and rehabilitation, including as an index of physiological recovery following concussion. However, concussion literature has predominantly emphasized HRV responses to physiological stressors, rather than psychological tasks that engage impaired domains such as attention, emotion regulation, and executive function.

OBJECTIVES

We systematically mapped the use of HRV during emotional and cognitive paradigms in adult concussion populations clarifying rationales for its application, the stimuli and measures employed, and state of science.

RESULTS

We identified 6,791 records, four meeting inclusion criteria. Paradigms included emotional film clips and cognitive tasks, with HRV indices spanning time-, frequency-, and nonlinear domains. Across studies, individuals with concussion demonstrated altered autonomic flexibility compared to control subjects, including blunted modulation, atypical valence-related responses, and compensatory increases in vagal activity. Methodological heterogeneity limited cross-study comparability.

CONCLUSION

This review highlights a critical evidence gap regarding HRV measurement in psychological contexts after adult concussion. Standardized HRV protocols, diverse samples, and longitudinal designs are needed to clarify recovery trajectories and further assess the value of HRV as a recovery biomarker after concussion.