Variability of signal sequences in turn-taking exchanges induces agency attribution in 10.5-mo-olds

We demonstrate that 10.5-mo-old infants—before understanding the symbolic contents encoded by unfamiliar signals—can recognize turn-taking interactions that serve communicative information transmission based on detecting variability in the signal sequences exchanged. Sensitivity to this abstract structural cue is sufficient to attribute communicative abilities and intentional agency to the interacting entities, as indicated by gaze following the agent's object-oriented turning to fixate its distal referent. When the entities exchanged identical signals only, no gaze following and agency attribution occurred. Infants' early sensitivity to variability in exchanged signal sequences can play an important role in social-cognitive development and language acquisition by helping infants recognize communicative interactions that can convey relevant information in various pragmatic contexts.