Effects of medical biofeedback trainings on acute stress by hybridizing heart rate variability and brain imaging

In this study, active and arousal elements of emotion associated with acute stress were systematically investigated with respect to the relations between the brain activity and autonomic nervous system. In this regard, we examined the differences in short-term heart rate variability (HRV) with respect to time-frequency domain characteristics, nonlinear features, and heart rhythm patterns, when breathing volitionally in a resonant frequency (RF) respiratory with International Affective Picture Systems (IAPS) triggered negative stimulus. In this regard, a sample-based event-related functional magnetic resonance imaging (efMRI) experiments were performed to verify the dynamic changes in brain lateralisation, and 105 healthy right-handed subjects participated in the HRV study while eight of them were randomly chosen to perform small sample based efMRI test. The experimental results suggest that when experiencing negative emotions, RF-based volitional breathing is sufficient to facilitate coherence of autonomic nervous system (ANS) performance, and shifted the brain activation toward left lateralized neural activity. In combination with the previous research on cerebral correlates of emotion, this study validated the feasibility of applying HRV biofeedback in the regulation of negative emotion in healthcare settings.