How trait impressions of faces shape subsequent mental state inferences

People form impressions of one another in a split second from faces. However, people also infer others’ momentary mental states on the basis of context—for example, one might infer that somebody feels encouraged from the fact that they are receiving constructive feedback. How do trait judgements of faces influence these context-based mental state inferences? In this Registered Report, we asked participants to infer the mental states of unfamiliar people, identified by their neutral faces, under specific contexts. To increase generalizability, we representatively sampled all stimuli from inclusive sets using computational methods. We tested four hypotheses: that trait impressions of faces (1) are correlated with subsequent mental state inferences in a range of contexts, (2) alter the dimensional space that underlies mental state inferences, (3) are associated with specific mental state dimensions in this space and (4) causally influence mental state inferences. We found evidence in support of all hypotheses. In this Stage 2 Registered Report, Lin et al. show that trait impressions of faces are correlated with and causally influence mental state inferences from the same faces.