Aesthetic preferences for unfamiliar faces are modulated by a combination of dynamic social cues

Facial expression, eye gaze, pupil size and head orientation are important social cues which indicate the emotional states and intentions of others. These cues can also modulate perceived attractiveness. However, it is unclear how they interact to
determine preferences in faces. We conducted 3 experiments, using ratings of facial attractiveness, to explore these interactions. In Experiment 1 we manipulated pupil size and gaze direction of faces and found that a preference for direct gaze was modulated by pupil size - faces with dilated rather than constricted pupils were perceived to be more attractive but only when gaze was directed at the observer. In Experiment 2, we investigated the effect of gaze shift and facial expression on perceived attractiveness. We found a significant interaction between these cues in that faces were rated to be the most attractive when they changed from neutral to smiling coupled with a gaze shift towards the viewer. In the final experiment, we investigated the role of head orientation, eye gaze and expression. Again we found that the effect of head orientation varied between happy and angry expressions. Our results suggest that cues to social engagement combine to enhance perceived attractiveness in unfamiliar faces.