The conceptual structure of face impressions.

Humans seamlessly infer the expanse of personality traits from others' facial appearance. These facial impressions are highly intercorrelated within a structure known as "face trait space." Research has extensively documented the facial features that underlie face impressions, thus outlining a bottom-up fixed architecture of face impressions, which cannot account for important ways impressions vary across perceivers. Classic theory in impression formation emphasized that perceivers use their lay conceptual beliefs about how personality traits correlate to form initial trait impressions, for instance, where trustworthiness of a target may inform impressions of their intelligence to the extent one believes the two traits are related. This considered, we explore the possibility that this lay "conceptual trait space"-how perceivers believe personality traits correlate in others-plays a role in face impressions, tethering face impressions to one another, thus shaping face trait space. In study 1, we found that conceptual and face trait space explain considerable variance in each other. In study 2, we found that participants with stronger conceptual associations between two traits judged those traits more similarly in faces. Importantly, using a face image classification task, we found in study 3 that participants with stronger conceptual associations between two traits used more similar facial features to make those two face trait impressions. Together, these findings suggest lay beliefs of how personality traits correlate may underlie trait impressions, and thus face trait space. This implies face impressions are not only derived bottom up from facial features, but also shaped by our conceptual beliefs.