Abstract
Human adults show better face recognition for own-race faces than other-race faces (e.g., Feingold, 1914; Meissner & Bringham, 2001). Developmental studies revealed that this recognition bias for own-race faces emerges in infancy (for a review, see Lee et al., 2011). At three months of age, infants can discriminate as readily between two own-race faces as between two other-race faces (Kelly et al., 2007, 2009). However, 9-month-old infants can only distinguish between own-race faces, whereas they have difficulty discriminating other-race faces. In this study, we examined the neural correlates for the development of own- and other-race face processing in infants aged 5 to 9 months using near-infrared spectroscopy (NIRS). We hypothesized the different patterns of hemodynamic responses to own-race and other-race faces between younger and older infants, paralleling the existing behavioral findings. We measured Japanese infants’ hemodynamic responses in the bilateral temporal regions during the presentation of East-Asian faces (own-race condition) and Caucasian faces (other-race condition). In each trial, infants were presented sequence of five color photographic images of different female faces (Figure 1). The hemodynamic responses to the faces were contrasted against the activation during the baseline period where five color images of vegetables were shown. We found that at 5 months, infants’ hemodynamic responses were higher for other-race faces than for own-race faces (Figure 2). In contrast, 8- and 9-month-olds showed the higher activation for own-race faces than other-race faces in the right temporal area. These results indicate that due to differential exposure to own- versus other-race faces, infants show differentiations in neural response between own- and other-race faces; this differentiation also undergoes developmental change, likely due to the increased exposure to own-race faces with increased age. Thus, early asymmetry in experience with own- and other-race faces has early impact on not only infants’ behavior but also neural activities.
Meeting abstract presented at VSS 2015