Joint action in gratitude and cooperation affect inter-brain connectivity for EEG

Recently several studies in the psychological and social field have investigated the social function of gratitude as a useful way for the consolidation of interpersonal joint-action and the implementation of prosocial behavior. Specifically, the present research wanted to explore if gratitude increased interpersonal cooperation, leading to an improvement in inter-brain synchronization and behavioral performance. Neural connectivity and cognitive performance of pairs of friends were recorded during the development of a joint attention task that involved a gift exchange at the beginning or halfway through the task. For the recording of subjects simultaneous brain activity an electroencephalogram (EEG) was used in hyperscanning. The results showed that after gift exchange there was an improvement in behavioral performance in terms of accuracy. For what concerns EEG, instead, an increase of delta and theta activation was observed in the dorsolateral prefrontal cortex (DLPFC). Furthermore, an increase in neural connectivity for delta and theta bands was observed. The present research provides a significant contribution to the exploration of the factors contributing to the strengthening of social bonds, underlining the importance of gratitude in the increase of cooperative and prosocial behavior.