Decoding Complex Emotions and Humanization Show Related Face Processing Effects

Inferring others' complex emotions is central to ascribing humanness to others. However, little past research has investigated the perceptual processes linking the inference of complex emotions to judging others' humanness. To this end, we disrupted the low-level perceptual processes typically employed in face processing via face inversion. Of interest was whether the inversion-driven deficits in complex emotion judgments and in humanness judgments were related. In three experiments, we find that disrupting efficient face processing via face inversion undermined the accurate decoding of complex emotions from the eyes (Experiments 1a, 1b, and 2) and triggered more dehumanized evaluations of target eye regions (Experiments 1a and 1b) and faces (Experiment 2). Critically, these inversion effects on emotion decoding and dehumanization were positively correlated. People who demonstrated stronger inversion effects on the accuracy of decoding complex emotions also demonstrated stronger inversion effects on dehumanizing evaluations. Taken together, these findings provide novel evidence that sensitivity to complex emotions and (de)humanization are related through a shared perceptual basis in efficient face processing.