Nonverbal communicative signals modulate attention to object properties.

We investigated whether the social context in which an object is experienced influences the encoding of its various properties. We hypothesized that when an object is observed in a communicative context, its intrinsic features (such as its shape) would be preferentially encoded at the expense of its extrinsic properties (such as its location). In the three experiments, participants were presented with brief movies, in which an actor either performed a non-communicative action towards one of five different meaningless objects, or communicatively pointed at one of them. A subsequent static image, in which either the location or the identity of an object changed, tested participants’ attention to these two kinds of information. Throughout the three experiments we found that communicative cues tended to facilitate identity change detection and to impede location change detection, while in the non-communicative contexts we did not find such a bidirectional effect of cueing. The results also revealed that the effect of the communicative context was due to the presence of ostensive-communicative signals before the object-directed action, and not to the pointing gesture per se. We propose that such an attentional bias forms an inherent part of human communication, and function to facilitate social learning by communication.