Camouflaged attention: covert attention is critical to social communication in natural settings

The evolution of the human eye's unique high contrast morphology allows people to communicate with a simple look. Yet overt looking is not always preferred in social situations. Do covert shifts in attention - those that occur without a concomitant shift of the eyes or head - support this need? In the present field study, we discretely recorded pedestrians' looks to a confederate who performed an action - raising his hand to the side of his head and saying 'Hey' into a phone (private action), or raising his hand to the side of his head in greeting (i.e. a static wave) and saying 'Hey' (public action). Critically, pedestrians were not looking at the confederate at the start of the action. Despite this, pedestrians looked more in response to the public action (wave) than private action (phone). We argue that the observed difference in looking responses must be due to pedestrians first attending to the confederate covertly in order to assess the intention of his action, and only signaling this attention with a look when socially appropriate (e.g. to respond to a public action). Though the functional utility of covert attention has rarely been considered outside of controlled laboratory tasks, these results provide the first demonstration that covert attention plays a critical role in guiding appropriate social looking behaviour.