Exploring Changes in Cardio-Respiratory Dynamics during Emotional Auditory Stimulation

This study investigates changes of cardio-respiratory coupling as affected by emotional elicitation. To quantitatively assess these effects, we analyze the relationship between electrocardiogram (ECG)-based autonomic measurements and respiratory dynamics during emotional stimulation using auditory stimuli. The protocol involved four sessions with increasing arousal levels. Our analysis revealed a significant decrease in coherence between cardiac and respiratory dynamics from baseline to arousal, indicating reduced coordination between heart rate variability (HRV) and respiration as arousal increased. Arousal sessions were associated with an increase in respiratory sinus arrhythmia (RSA) gain at the frequency of maximum coherence, and a significant decrease in the high-frequency spectral power of the respiratory signal. These findings suggest that, as arousal intensifies, decreased respiratory variability may reflect a compensatory mechanism where respiration exerts greater influence on heart rate to maintain physiological stability. Conversely, the study highlights the importance that assessment of cardio-respiratory coupling might have in characterizing emotional arousal.