Reactive movements of non-humanoid robots cause intention attribution in humans

An artifact´s behavior must be easily construed and interpreted as meaningful signals in a social or working context. In order to design such an artifact´s behavior, we could exploit human psychological functions - theory of mind (ToM) - the ability to interpret other people´s behavior in terms of intentional causal mental states such as beliefs, desires and intentions. In order to apply theory of mind to human-robot interaction, the mechanism that trigger intention attribution must be revealed. The present study examined the effect of reactive movements performed by a non-humanoid robot, including different shaped artifact: chair and cube, on the intention attribution. The result indicated that whether or not humans could construe behaviors of an artifact in terms of its goal depends on how human could attribute intention to the artifact and that reactive movements would be a cue for such mental state attribution.