Emotional Expression Help Regulate the Appropriate Level of Cooperation with Agents

People often anthropomorphize agents and show social concern for the agents' goals. Whereas this can be useful to build human-agent cooperation in some settings, in others it can be counterproductive - e.g., when people risk themselves to help a robot. A mechanism, thus, is needed to regulate how much cooperation people show towards agents, according to the context. Here, we show that emotion expressions can be a powerful mechanism to help people identify the appropriate level of cooperation given the situation. In the present study, participants (n=379) engaged in a 20-round iterated prisoner's dilemma game with agents that showed emotional expressions that reflected a preference for maximizing its own interests versus maximizing the participants' interests. Accordingly, the results showed that participants focused significantly more on their own interests when facing the agent that expressed emotions favoring the participants' outcome; moreover, this treatment was more successful in steering the participants' focus to their own interests than showing no emotion. These findings reveal that, in addition to helping build cooperation, as shown in prior work, emotion expression can play a central role in mitigating some negative consequences of anthropomorphizing agents.