Emotion regulation after acquired brain injury: a study of heart rate variability, attentional control, and psychophysiology.

Primary objective: To examine the efficacy of heart rate variability biofeedback (HRV-BF) to treat emotional dysregulation in persons with acquired brain injury. Design: A secondary analysis of a quasi-experimental study which enrolled 13 individuals with severe chronic acquired brain injury participating in a community-based programme. Response-to-treatment was measured with two HRV resonance indices (low frequency activity [LF] and low frequency/high frequency ratio [LF/HF]). Main outcome: Behavior Rating Inventory of Executive Function-informant report (emotional control subscale [EC]). Results: Results show significant correlation between LF and EC with higher LF activity associated with greater emotional control; the association between LF/HF pre-post-change score and EC is not statistically significant. A moderation model, however, demonstrates a significant influence of attention on the relation between LF/HF change and EC when attention level is high, with an increase in LF/HF activity associated with greater emotional control. Conclusions: HRV-BF is associated with large increases in HRV, and it appears to be useful for the treatment of emotional dysregulation in individuals with severe acquired brain injury. Attention training may enhance an individual's emotional control.