Predominance of eyes and surface information for face race categorization

Isabelle Bülthoff,Regine G M Armann,Christian Wallraven,Wonmo Jung

doi:10.1038/s41598-021-81476-1

Isabelle Bülthoff, Regine G M Armann + Show 2 more

Open Access

https://doi.org/10.1038/s41598-021-81476-1

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Abstract

Faces can be categorized in various ways, for example as male or female or as belonging to a specific biogeographic ancestry (race). Here we tested the importance of the main facial features for race perception. We exchanged inner facial features (eyes, mouth or nose), face contour (everything but those) or texture (surface information) between Asian and Caucasian faces. Features were exchanged one at a time, creating for each Asian/Caucasian face pair ten facial variations of the original face pair. German and Korean participants performed a race classification task on all faces presented in random order. The results show that eyes and texture are major determinants of perceived biogeographic ancestry for both groups of participants and for both face types. Inserting these features in a face of another race changed its perceived biogeographic ancestry. Contour, nose and mouth, in that order, had decreasing and much weaker influence on race perception for both participant groups. Exchanging those features did not induce a change of perceived biogeographic ancestry. In our study, all manipulated features were imbedded in natural looking faces, which were shown in an off-frontal view. Our findings confirm and extend previous studies investigating the importance of various facial features for race perception.

Highlights

Faces can be categorized in various ways, for example as male or female or as belonging to a specific biogeographic ancestry
One main hypothesis is that they rely on facial features that have been optimized for discriminating between faces of their race of expertise, features that might not be best for discriminating between other-race faces
For the German group, the interaction between both factors was significant (F(1.93, 90.62) = 11.58, p < 0.001, ηp2 = 0.198) indicating that the facial alterations affected the classification of faces derived from Asian and Caucasian parents differently depending on which facial feature was exchanged

Summary

Introduction

Faces can be categorized in various ways, for example as male or female or as belonging to a specific biogeographic ancestry (race). Nose and mouth, in that order, had decreasing and much weaker influence on race perception for both participant groups Exchanging those features did not induce a change of perceived biogeographic ancestry. Experimental evidence reports that observers belonging to different racial background rely on different facial features to describe faces[13] This reflects the fact that faces of different races differ in terms of their facial features Other studies have suggested that East-Asians and Westerners look at faces (and scenes) differently because of their different cultural b ackgrounds[19,20] These findings are discussed in terms of stronger holistic viewing in Asian participants and more analytic strategies in Caucasian participants and/or reliance on different facial cues in both groups. Eye tracking studies have reported that Westerners distribute their gaze predominantly on eyes and mouth whereas East-Asians fixate more the center of the face (the nose), which might correspond to a more holistic visual processing of East-Asians than W esterners2122, but see in contrast[23]

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