Human face-selective cortex does not distinguish between members of a racial outgroup

Abstract

People often fail to individuate members of social outgroups, a phenomenon known as the outgroup homogeneity effect. Here, we used fMRI repetition suppression to investigate the neural representation underlying this effect. In a pre-registered study, White human perceivers (N = 29) responded to pairs of faces depicting White or Black targets. In each pair, the second face depicted either the same target as the first face, a different target from the same race, or a scrambled face outline. We localized face-selective neural regions via an independent task, and demonstrated that neural activity in the fusiform face area distinguished different faces only when targets belonged to the perceivers’ racial ingroup (White). By contrast, face-selective cortex did not discriminate between other-race individuals. Moreover, across two studies (total N = 67) perceivers were slower to discriminate between different outgroup members and remembered them to a lesser extent. Together, these results suggest that the outgroup homogeneity effect arises when early-to-mid-level visual processing results in an erroneous overlap of representations of outgroup members.

The Social Neuroscience of Prejudice

“…More recent work, which examined the effect of race on a phenomenon called "repetition suppression," suggests that prioritized ingroup processing in the fusiform contributes to the outgroup homogeneity effect, which, similar to the own-race bias effect, refers to people's tendency to view outgroup members as less distinguishable than ingroup members (Hughes et al, 2019;Reggev et al, 2020).…”

Three‐level meta‐analysis of the other‐race bias in facial identification

“…The authors also demonstrated that memory differences between the own‐race and other‐race faces correlated with activation in left fusiform cortex. More recent works also found the fusiform region is related to the outgroup homogeneity effect (Hughes et al, 2019; Reggev et al, 2020).…”

The hippocampus shows an own‐age bias during unfamiliar face viewing

“…If face repetition suppression effects reflect modulation of processes contributing to the identification of individual faces (Hermann et al, 2017), then we might expect that own‐age faces would elicit a greater suppression effect than other‐age faces, which we did not observe. However, one limitation of the present design is that we only examined repetition effects for identical repeats and did not include a condition that could examine ‘release from suppression’ (e.g., Goh et al, 2010; Reggev et al, 2020). Recently, Reggev et al (2020) argued in favour of a perceptual expertise account of own‐race biases based on findings of greater release from suppression for own‐race relative to other‐race faces.…”

“…However, one limitation of the present design is that we only examined repetition effects for identical repeats and did not include a condition that could examine ‘release from suppression’ (e.g., Goh et al, 2010; Reggev et al, 2020). Recently, Reggev et al (2020) argued in favour of a perceptual expertise account of own‐race biases based on findings of greater release from suppression for own‐race relative to other‐race faces. Future research employing designs that allow measurement of release from suppression is needed to pursue this issue.…”