Fixations and Fixation Shifts in Own-Race and Other-Race Face Pairs at Three, Six and Nine Months.

Caucasian infants were presented 15 pairs of Caucasian own-race faces and 15 pairs of African other-race faces. The infants were assessed longitudinally at ages three, six and nine months. Two measures were obtained from the infants' eye-movements: (1) the length of fixations on either stimulus of a pair presented for 5.5 s (fixation duration) and (2) the amount of fixation shifts between the two stimuli (shift frequency). The study analyzes the changes in both measures with age and across the within-race face pair presentations. Despite general age-related improvements reflected in shorter fixation durations and a higher shift frequency, the results reveal differences between African face pairs and Caucasian face pairs at six and nine months. During the first trials (spontaneous looking behavior) the infants shift more often between the Caucasian own-race faces than between the African other-race faces. The fixation durations, however, which are typically of focus in Visual Pair Preference Tasks, do not differ significantly between the face races. The results are interpreted in terms of processing differences for own-race faces and the emerging Other-Race-Effect by six months of age. Furthermore, the usability of fixation duration as the only measure in the pair comparison setting is discussed.