Can perceptual expertise accountfor the own-race bias in face recognition? A split-brain study

Abstract

The own-race bias (ORB) in facial recognition is characterised by increased accuracy in recognition of individuals from one's own racial group, relative to individuals from other racial groups. Here we report data from a split-brain patient indicating that the ORB may be tied to functions lateralised in the right cerebral hemisphere. Patient JW (a Caucasian) performed a delayed match-to-sample task for faces that varied both the race of the facial memoranda—Caucasian or Japanese—and the cerebral hemisphere performing the task. While JW's left hemisphere showed no effect of race on facial recognition, his right hemisphere demonstrated a significant performance advantage for Caucasian faces. These findings are discussed in relation to stimulus familiarity and the development of perceptual expertise.

Acknowledgments

We thank Dr Matt Roser and Gagandeep Wig for helpful comments, Dr Fumihiko Itagaki for the stimuli used in this study, and Dr George Wolford for statistical advice. We are also grateful for JW and his willingness to participate. DJT was supported in part by NIMH grant 1R03MH070901-01.

Notes

Nine neurologically normal Caucasian participants were also tested, each on one single occasion. They were drawn from the pool of undergraduate students at Dartmouth College. All participants gave informed consent to the experiment and received either class credit or financial compensation for their involvement. Face recognition in these subjects was characterised by a significant effect of race, F(1, 8) = 14.79, MSE = 69.44, p > .005, but there was no effect of visual field, F(1, 8) = 0.26, MSE = 1.00, and no interaction, F(1, 8) = 0.10, MSE = 0.44. Mean recognition performance levels for the race effect were: 81.26% (SE 4.34%) for Japanese and 92.82% (SE 1.65%) for Caucasian faces.