If you trust me, I will trust you: the role of reciprocity in human-robot trust.

Abstract

Trust is fundamental in human-human and human-robot interaction. Extensive evidence has shown that trust among humans is sustained by reciprocity, whereas knowledge on reciprocal dynamics of trust in human-robot interaction is very limited. To investigate reciprocity in human-robot trust, we designed a joint task in which a human participant and a humanoid robot made perceptual judgments while signaling their trust in the partner. The robot's trust was dynamically manipulated along the experiment. Results show that participants were less willing to learn from a robot that was showing high trust in them. However, participants were unwilling to overtly disclose their distrust to the robot if they expected future interactions with it, suggesting the emergence of reciprocity in their overt expression of trust. Importantly, these effects disappeared when participants interacted with a computer. Our findings may have an impact on the design of robots that could effectively collaborate with humans.