Iris colour modulates gaze-mediated attentional orienting in Japanese children

Abstract

Abstract Human gaze perception is supported by the distinctive morphology of the human eye, yet it remains unclear whether natural variation in iris colour modulates gaze-mediated attentional orienting. We examined this question in two gaze-cueing experiments with Japanese children aged 6 to 11 years, a population with limited everyday exposure to light-coloured irises. Participants completed a speeded localization task in which a face or eye-region stimulus looked left or right before a target appeared. Stimuli varied in iris colour (brown and blue) and race-related appearance (Asian and White), and were presented either as full faces (experiment 1) or isolated eye regions (experiment 2). In experiment 1, gaze-cueing effects were larger for brown than blue irises, and this modulation was most pronounced for Asian faces. In experiment 2, using isolated eye-region stimuli, gaze-cueing effects were again larger for brown than blue irises across Asian- and White-origin eye regions. These findings show that iris colour can modulate gaze-mediated attentional orienting in childhood. The pattern is consistent with the possibility that children's social attention is sensitive to locally familiar ocular features. However, because the present study tested a single population, cross-cultural work is needed to determine whether this effect reflects local visual experience or a more general advantage for brown irises.