Social Attention to Infants
P.0.05. White participants showed the opposite pattern, respond- ing to probes more quickly when they appeared in the same location as infant face than adult face distractors for White infant– adult face pairs, t19 = 3.54, P = 0.002, but not for South Asian infant–adult face pairs, t19 = 1.67, P.0.05. (A similar analysis on error rates showed no significant effects, all Ps.0.5, confirming that the RT pattern cannot be explained in terms of a speed– accuracy trade-off; see Table 2.)
These results suggest that the attentional prioritization of kindenschema is modulated by the race of the infant and of the perceiver. In the current experiment, infant faces captured attention only when they matched the race of the participant. This was true for both South Asian and White participants, showing that this pattern of data was not due to perceptual artifacts in the stimuli. To what, then, can we attribute the effects?
One possibility is simply that other-race infant faces, like other- race adults faces, tend not to be processed holistically, and thus that they were not individuated from adult faces in the current study. This lack of individuation might have resulted because the detection of a racial cue truncates processing , . Simple cues such as skin tone are sufficient for racial category to be recognized [20–22], but perceiving kindenschema (e.g., big eyes, small nose, large forehead) requires more configural processing; that is, features can only be recognized as large or small in the context of the entire face/head. Assuming the scale of face perception proceeds across time from the extraction of simpler features (e.g., skin tone to determine race) to more complex configurations (e.g., size of eyes within the face) [23–26], then early social categorization effects might moderate the influence of kindenschema.
Another possibility is that participants in the current study lacked the expertise to individuate other-race faces as efficiently as own-race faces. It is also possible that this relative inability to individuate other-race faces was confined primarily to other-race infant faces. The study was conducted in an ethnically diverse city (with almost 20% of the population self-identifying as South Asian) and all of our participants were UK-born and thus were likely to have had a reasonable amount of interracial contact, particularly our minority South Asian participants. Given our participants’ age (19–20 years) and status (undergraduate university students), however, it is conceivable that their prior interracial experiences were with other-race adults more than with other-race infants.
This is not to say our participants failed to recognize infant faces as such; it is merely to suggest that factors that undermine individuation (i.e., social categorization, lack of experience) might also offset the effects of kindenschema. Another factor, however, might be the relative differences in arousal engendered by own-
race versus other-race adult faces. Brosch and colleagues ,  suggested that infant faces capture attention because their biological significance makes them more arousing—and thus more salient—than other categories of stimuli. Differential positivity or arousal associated with infant versus adult faces alone cannot account for the attentional prioritization of infant faces in the current data, however: Within-race comparisons indicated that both own- and other-race infant faces were rated as more pleasant and more arousing than their adult counterparts in pilot testing (see Table 3), and yet attentional capture by infant faces only occurred for own-race faces. Interestingly, however, between-race comparisons indicated that other-race adult faces were rated as more arousing than own-race adult faces by both South Asian and White participants (t7 = 4.85 P,0.001 and t7 = 3.29 P = 0.013, respectively). It may be that within the context of viewing both own- and other-race faces, the greater arousal level associated with other-race adult faces was sufficient to interfere with the attentional prioritization of other-race infant faces, despite other- race infant faces being rated as more arousing than their adult counterparts. This possibility is the subject of ongoing investigation.
In providing evidence that attentional capture by infant faces is modulated by the race of the faces and of the perceivers viewing them, these results also suggest a qualification of the cooperative breeding hypothesis . According to this hypothesis, infant caregiving is distributed across members of the species (kin and non-kin) rather than the responsibility of the parents alone—a form of caregiving called allo-parenting. This notion is compatible with Brosch and colleagues’ (8) evidence for attentional prioriti- zation of human but not non-human infant faces. Our results, however, suggests that the attentional filter imposed by this presumably evolutionary drive toward allo-parenting is tuned to the individual’s environment and experience. For those without frequent interracial contact, particularly with other-race infants, the attentional filter may operate more efficiently at the level of social category rather than species: In the absence of sufficient motivation , , expertise , , or training ,  to individuate other-race infant faces, these individuals may be less sensitive to face-specific care-seeking cues such as kindenschema when those cues are emitted by other-race versus own-race infants.
Materials and Methods
Participants and Design
Participants were 20 South Asian and 20 White female UK- born undergraduates at the University of Birmingham (mean ages 20.25 years and 19.63 years, respectively). All participants were right-handed, had normal or corrected-to-normal vision, and received course credits for their participation. The experiment was based on a 2 (probe location age: infant, adult) 62 (probe location
Table 2. Mean probe-detection error rates (61 standard error) experimental study (64 trials per condition).
as a function of distractor age, distractor race, and participant race;
South Asian Participants
South Asian Distractors
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South Asian Distractors
September 2010 | Volume 5 | Issue 9 | e12509