Wollaston's effect in infants: Do infants integrate eye and head information in gaze perception?

The current study examined infants' sensitivity to Wollaston's effect: When identical eyes are placed in differently angled faces, the perceived gaze direction shifts toward the orientation of the face such that physically, the direct gaze is perceived as averted toward the orientation of the face. Consistent with Wollaston's effect, we found that looking toward direct and averted gaze by 4- to 5- and 7- to 8-month-olds (n = 40) was affected by the head orientation context. These results demonstrate that infants aged 4 to 5 and 7 to 8 months integrate eye and head information to perceive another's gaze direction. In light of recent psychophysical findings, the current results suggest that the visual function supporting constant gaze perception across head rotation is already at work by 4 to 5 months of age.