Humans spontaneously attend to faces and eyes. Recent findings, however, suggest that this social attentional biasing may not be driven by the social value of faces but by general factors, like stimulus content, visual context, or task settings. Here, we investigated whether the stimulus content factors of global luminance, featural configuration, and perceived attractiveness may independently drive social attentional biasing. Six experiments were run. In each, participants completed a dot-probe task where the presentation of a face, a house, and two neutral images was followed by the presentation of a response target at one of those locations. Experiments 1 and 2 assessed social attentional biasing when the face had higher overall global luminance. Experiments 3 and 4 assessed social attentional biasing when the face (but not the comparison house) retained the typical canonical configuration of internal features. Experiments 5 and 6 examined social attentional biasing when the face was more attractive than the house. Experiments 1, 3, and 5 measured manual responses when participants were instructed to maintain fixation. Experiments 2, 4, and 6 measured both manual and oculomotor responses when no instructions about eye movements were provided. The results indicated no reliable social attentional biasing in Experiments 1 to 5, however, a reliable saccadic bias toward the eyes of attractive upright faces was found in Experiment 6. Together, these results show that perceived facial attractiveness may be an important general factor in social attentional biasing.
Public Significance StatementIt is commonly understood that humans attend to faces preferentially. Recent work has challenged the notion that this effect is attributable to the inherent social value of faces by showing that spontaneous attending to faces is abolished when nonsocial factors-specifically, content within faces (e.g., luminance, configuration, attractiveness), contexts within which faces are presented in (e.g., background information), and task requirements (e.g., method of response)-are systematically controlled. Here, we show that attending to faces may be biased by the content factor of perceived facial attractiveness and not other factors like global luminance or featural configuration. This suggests that perceived facial attractiveness may be a key factor in instantiating social attentional biasing.