Integrating Intersubject Biofeedback in Hyperscanning visual affective experiment: proof of concept and preliminary results on HRV dynamics

Recently, multimodal hyperscanning techniques have gained significant interest, especially in analyzing neurophysiological dynamics during cognitive, neurorehabilitation, affective tasks, and social interactions. Moreover, several works have integrated neurofeedback stimuli in hyperscanning studies to better explain the interactions among the involved subjects. This study proposes a novel intersubject biofeedback stimulus integration during a hyperscanning visual affective experiment on dyadic pairs. Electroencephalographic (EEG) and electrocardiographic (ECG) signals were simultaneously acquired through a customized single physiological system monitoring connected to both participants. Interesting preliminary results on 24 dyads showed that adding intersubject biofeedback might induce variations in heart rate variability (HRV) dynamics in both subjects. Differences in the HRV cross-entropy indices between baseline periods and visual affective tasks were also observed. These results pave the way for future deeper investigations of the neural mechanisms behind multiple subject interactions through hyperscanning approaches.Clinical Relevance-The study of biofeedback in hyperscanning studies might be helpful to characterize better the neurological interactions between subjects, as well as to confirm the potentiality regarding the use of the hyperscanning paradigm in psychophysiological applications and clinical practice.