A detection advantage for facial threat in the absence of anger

Quickly and accurately perceiving the potential for aggression in others is adaptive and beneficial for self-protection. Superior detection of facial threat is demonstrated by studies in which transient threat indices (i.e., angry expressions) are identified more efficiently than are transient approach indices (i.e., happy expressions). Not all signs of facial threat are temporary, however: Persistent, biologically based craniofacial attributes (e.g., low eyebrow ridge) are also associated with a perceived propensity for aggression. It remains unclear whether such static properties of the face elicit comparable attentional biases. We used a novel visual search task of faces for the present study that lacked explicit displays of emotion, but varied on perceived threat via manipulated craniofacial structure. A search advantage for threatening facial elements surfaced, suggesting that efficient detection of threat is not limited to the perception of anger, but rather extends to more latent facial signals of aggressive potential. Although all stimuli were primarily identified as emotionally neutral, thus confirming that the effect does not require emotional content, individual variation in the perception of structurally threatening faces as angry was associated with a greater detection advantage. These results indicate that attributing anger to objectively emotionless faces may serve as a mechanism for their heightened salience and influence important facets of social perception and interaction.