Perceptual Dehumanization Theory: A Critique

Central to perceptual dehumanization theory (PDT) is the claim that full engagement of a putative module for the visual analysis of faces is necessary in order to recognize the humanity or personhood of observed individuals. According to this view, the faces of outgroup members do not engage domain-specific face processing fully or typically and are instead processed in a manner akin to how the brain processes objects. Consequently, outgroup members are attributed less humanity than ingroup members. To the extent that groups are perceptually dehumanized, they are hypothesized to be vulnerable to harm. In our article, we challenge several of the fundamental assumptions underlying this theory and question the empirical evidence in its favor. We begin by illustrating the extent to which the existence of domain-specific face processing is contested within the vision science literature. Next, we interrogate empirical evidence that appears to support PDT and suggest that alternative explanations for prominent findings in the field are more likely. In the closing sections of the article, we reflect on the broader logic of the theory and highlight some underlying inconsistencies.