What Hyperscanning and Brain Connectivity for Hemodynamic (fNIRS), Electrophysiological (EEG) and Behavioral Measures Can Tell Us About Prosocial Behavior

Objective: Recently the interest in neuroscience has allowed us to investigate the neural correlates underlying different social interactional contexts, such as prosocial behavior. The present study aimed to observe the behavioral synchronization underlying the cognitive performance and brain-to-brain coupling mechanisms during a co-operative task, through an hyperscanning paradigm (coupled participants, donors, and receivers), involving a gift exchange. Method: To this aim, neural activity was recorded through the use of electroencephalography (EEG) and hemodynamic brain activity (functional Near-Infrared Spectroscopy—fNIRS). The neural and behavioral (performance accuracy—ACC and reaction times—RTs) measures were subsequently correlated among them to test the direct correspondence and the correlation of these three levels. Results: From the results, an increase in behavioral synchronization has emerged, with an improved performance after the gift exchange. Moreover, an increase of neural (EEG, fNIRS) interbrain connectivity has emerged after gift exchange, with a maximum of brain-to-brain coupling in the frontal area for EEG delta and theta bands and hemodynamic activity. Finally, a direct correlation between behavioral, EEG, and fNIRS data has emerged. Conclusion: Thus, prosocial behavior is able to improve the cognitive-behavioral performance and electrophysiological and hemodynamic interindividual synchronization, showing the direct relationship between this three-order synchronization.