Prisoner’s Dilemma game: Participants were more cooperative when they saw each other compared to when they could not, and when receiving reliable compared to unreliable or no feedback

The Interplay Between Face-to-Face Contact and Feedback on Cooperation During Real-Life Interactions. Friederike Behrens, Mariska E. Kret. Journal of Nonverbal Behavior, September 11 2019. https://link.springer.com/article/10.1007/s10919-019-00314-1

Abstract: Cooperation forms the basis of our society and becomes increasingly essential during times of globalization. However, despite technological developments people still prefer to meet face-to-face, which has been shown to foster cooperation. However, what is still unclear is how this beneficial effect depends on what people know about their interaction partner. To examine this question, 58 dyads played an iterated Prisoner’s Dilemma game, sometimes facing each other, sometimes without face contact. Additionally, explicit feedback regarding their decisions was manipulated between dyads. The results revealed that participants were more cooperative when they saw each other compared to when they could not, and when receiving reliable compared to unreliable or no feedback. Contradicting our hypothesis that participants would rely more on nonverbal communication in the absence of explicit information, we observed that the two sources of information operated independently on cooperative behavior. Interestingly, although individuals mostly relied on explicit information if available, participants still cooperated more after their partner defected with face-to-face contact compared to no face-to-face contact. The results of our study have implications for real-life interactions, suggesting that face-to-face contact has beneficial effects on prosocial behavior even if people cannot verify whether their selfless acts are being reciprocated.

Keywords: Cooperation Face-to-face contact Feedback Dyadic interaction Nonverbal communication Social dilemmas

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participants still cooperated more after their partner defected with faceto-face-contact. Hence, people might be more "forgiving" when facing their partner when he/she defects and theefore encourage the defecting partner to return to cooperation by opting for a cooperative decision themselves.