No evidence for enhanced likeability and social motivation towards robots after synchrony experience

A wealth of social psychology studies suggests that moving in synchrony with another person can positively influence their likeability and prosocial behavior towards them. Recently, human-robot interaction (HRI) researchers have started to develop real-time, adaptive synchronous movement algorithms for social robots. However, little is known how socially beneficial synchronous movements with a robot actually are. We predicted that moving in synchrony with a robot would improve its likeability and participants’ social motivation towards the robot, as measured by the number of questions asked during a free interaction period. Using a between-subjects design, we implemented the synchrony manipulation via a drawing task. Contrary to predictions, we found no evidence that participants who moved in synchrony with the robot rated it as more likeable or asked it more questions. By including validated behavioral and neural measures, future studies can generate a better and more objective estimation of synchrony’s effects on rapport with social robots.