Gaze allocation in face-to-face communication is affected primarily by task structure and social context, not stimulus-driven factors.

Gaze allocation to human faces has recently been shown to be greatly dependent on the social context. However, what has not been considered explicitly here, is how gaze allocation may be supportive of the specific task that individuals carry out. In the present study, we combined these two insights. We investigated (1) how gaze allocation to facial features in face-to-face communication is dependent on the task-structure and (2) how gaze allocation to facial features is dependent on the gaze behavior of an interacting partner. To this end, participants and a confederate were asked to converse, while their eye movements were monitored using a state-of-the-art dual eye-tracking system. This system is unique in that participants can look each other directly in the eyes. We report that gaze allocation depends on the sub-task being carried out (speaking vs. listening). Moreover, we show that a confederate's gaze shift away from the participants affects their gaze allocation more than a gaze shift towards them. In a second experiment, we show that this gaze-guidance effect is not primarily stimulus-driven. We assert that gaze guidance elicited by the confederate looking away is related to the participants' sub-task of monitoring the confederate for when they can begin speaking. This study exemplifies the importance of both task structure and social context for gaze allocation during face-to-face communication.