Socio-cognitive, expertise-based and appearance-based accounts of the other-‘race’ effect in face perception: A label-based systematic review of neuroimaging results

Abstract

Two competing theories explain the other-‘race’ effect (ORE) either by greater perceptual expertise to same-‘race’ (SR) faces or by social categorization of other-‘race’ (OR) faces at the expense of individuation. To assess expertise and categorization contributions to the ORE, a promising—yet overlooked—approach is comparing activations for different other-‘races’. We present a label-based systematic review of neuroimaging studies reporting increased activity in response to OR faces (African, Caucasian, or Asian) when compared with the SR of participants. Hypothetically, while common activations would reflect general aspects of OR perception, ‘race’-preferential ones would represent effects of ‘race’-specific visual appearance. We find that several studies report activation of occipito-temporal and midcingulate areas in response to faces across different other-‘races’, presumably due to high demand on the visual system and category processing. Another area reported in response to all OR faces, the caudate nucleus, suggests the involvement of socio-affective processes and behavioural regulation. Overall, our results support hybrid models—both expertise and social categorization contribute to the ORE, but they provide little evidence for reduced motivation to process OR faces. Additionally, we identify areas preferentially responding to specific OR faces, reflecting effects of visual appearance.