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Children have been shown to prefer faces rated as highly attractive by adults over faces rated as quite unattractive. We investigated to what extent this agreement holds not only for the general direction of preferences but for preference strengths as well. In a choice experiment, we presented 40 nine-year-old girls and their mothers and 40 twelve-year-old girls and their mothers with pairs of women’s and girls’ faces and asked the subjects to pick the face that appeared prettier to them. Preference frequencies and simple attractiveness scales derived from these preference frequencies by fitting the Bradley–Terry–Luce rule (Luce, D. R. (1959). Individual choice behavior: a theoretical analysis. New York: Wiley) were compared across subject groups. For the women’s faces, we found no difference in preferences between nine-year-olds, twelve-year-olds, and adults, neither in direction nor in strength. For the girls’ faces, we also found no major differences in preference direction, however, we did find reliable differences in preference strengths. To a considerable part these differences were due to the fact that the children showed less pronounced preferences between face stimuli than the adults. These results suggest a role of developmental factors in the perception of facial attractiveness.

Facial attractiveness plays a major role in the formation of interpersonal social judgements (for a review see e.g. Hatfield & Sprecher, 1986). Many studies showed that attractive individuals enjoy advantages over less attractive people. They are perceived as more likeable, kind, and intelligent (Berscheid & Walster, 1974) and are more likely to be professionally successful than their less attractive counterparts (Frieze, Olson & Russel, 1991). Even children have been shown to be differentially evaluated on the basis of their physical appearance, both by peers (Dion, 1973) and by adults Clifford and Walster, 1973 and Felson, 1981. Facial attractiveness has been demonstrated to influence the status within the peer group (Berscheid & Walster, 1974) as well as evaluation of school performance by teachers Clifford and Walster, 1973 and Felson, 1981. Such biases in favor of attractive individuals were for a long time thought to be based on prevalent socio-cultural norms. Judgements of attractiveness were viewed as depending largely on fashion and the underlying mechanisms were viewed as being only gradually acquired through internalization of prevalent socio-cultural stereotypes in the course of individual development. Over the past 10 years, however, evidence has accumulated which suggests that the perception of facial attractiveness may be remarkably similar across both different cultures Bernstein et al., 1982, Cunningham et al., 1995, Jones and Hill, 1993 and Perrett et al., 1994 and different age groups Cavior and Lombardi, 1973 and Cross and Cross, 1971. The results of studies examining the influence of the beholder’s age on the perception of facial attractiveness Langlois et al., 1987 and Samuels and Ewy, 1985 in fact indicate that already children as young as three months old are able to discriminate between rather attractive and unattractive faces. The perception of facial attractiveness, therefore, seems to have a sizeable biological basis and to be not an arbitrary product of social norms. But while matters seem fairly clear at the extremes of the attractiveness continuum, it is much less clear to what degree people at different ages differ in the extent to which they perceive differences between less extreme stimuli and to what degree the type of stimulus and experiential or maturational factors play a role in mediating this ability. Recent work on the neural mechanisms underlying face processing abilities indicates that maturational factors indeed play a role in several aspects of face processing. For instance, Taylor, McCarthy, Saliba and Degiovanni (1999) demonstrated a gradual maturation for a face-specific electrophysiological component throughout childhood and adolescence. Their study seems remarkable in that it did not involve a specific task which may have confounded face perception with other activities such as recognition or recall but simply compared neural responses when viewing faces with neural responses to other classes of objects in different age groups. On the basis of their result the authors suggest that face processing undergoes a gradual, quantitative maturation but no qualitative change during individual development. With regard to the processing of facial expression, Kolb, Wilson and Taylor (1992) found that performance levels of eight- to thirteen-year-old children in an expression matching task was similar to the performance of adults with frontal lobe injury, implying that some frontal lobe regions involved in this task may not yet have matured in this age group. In this context, data implicating the left frontal lobe in judgements of facial attractiveness (Nakamura et al., 1998) provide circumstantial evidence to suggest a role of developmental factors in the perception of facial attractiveness, as the frontal lobes are areas in the human brain which are subject to great modifications in the course of individual development. In cognitive research into the development of face recognition it is widely accepted that faces are a special class of visual objects from the very beginning in that they are preferred by infants over non-faces Dzurawiec and Ellis, 1986 and Goren et al., 1975. However, it is also clear that there is a considerable amount of development involved in the ability to discriminate and recognize faces. A two-process theory has been put forward to account for both these observations in infants (Morton & Johnson, 1991) and a considerable amount of work has been devoted to investigating the trajectory of face recognition abilities through early and middle childhood into adulthood (for reviews see Ellis, 1992; Carey, 1992). The influence of factors such as distinctiveness (Johnston & Ellis, 1995) and inversion Carey and Diamond, 1977, Carey et al., 1980 and Flin, 1985 on the ability to discriminate and recognize faces at different ages has been examined. The results indicate that children’s face recognition is less disrupted by the inversion of faces than is adults’, that children may be less able to use distinctiveness information in face recognition tasks, and, not surprisingly, that they are less able to correctly identify photographs of a person taken 20 years apart and are more susceptible to being deceived by irrelevant paraphernalia when performing a face recognition task. To account for such observations, Carey (1992) suggested that some of the age-related differences in face processing may be due to the fact that children’s face processing may rely more on isolated features of a face and may tend to disregard the configurational information present in a face. Ellis and Flin (1990), on the other hand, propose that the developmental changes observed are due to the fact that older individuals are simply able to extract more information from a face within a given amount of time. In view of the above presented evidence for the presence of developmental factors in various aspects of face processing, the comparative paucity of work dealing with the development of mechanisms underlying the perception of facial attractiveness in adults and children at different ages is surprising. While there is a considerable amount of work on infants’ basic abilities and extensive research on the social consequences of an individual’s facial attractiveness, very little is known about the extent to which children’s and adults’ preferences are the same and the extent to which such preferences are modified by the types of stimuli used. From a developmental point of view it appears possible that, whereas children may prefer faces rated as very attractive by adults over faces rated as quite unattractive, the children’s preferences may be less pronounced than those of the adults, i.e., they may have difficulty perceiving as fine differences in facial attractiveness as adults do. Prior work did not address this point and rather focused on the question of whether children are basically able to make distinctions based on attractiveness, and whether these distinctions are in the same direction as the ones adults make. There is ample evidence that this is already the case at a very early age. But whether the preferences of children are already as pronounced as those of adults is largely unclear. On the basis of the above mentioned neurophysiological data one might expect more pronounced preferences in older subjects on purely brain maturational grounds which, of course, will also be correlated with the experiential factors emerging from cognitive studies. Furthermore, stimulus attributes may play a role in mediating children’s ability to discriminate between attractive and less attractive faces. For example, children may perceive a greater variation in children’s faces than in adults’ faces. This might either be the case because such faces are of greater social importance to them than adults’ faces as attractiveness represents a salient category for social comparison with peers (Dion, 1973), or because school-age children have comparatively more every-day experience with this type of face. Such an “own-age effect” might be analogous to the well-known “own-race bias” Brigham, 1986, Malpass and Kravitz, 1969 and Shepherd and Deregowsky, 1981, where it has been demonstrated to be easier for people to recognize members of their own race over members of a different race. With regard to “own-race” effects in the perception of facial attractiveness, recent research has also shown that, while there are great overall consistencies across cultures, the within-culture agreement tends to be somewhat larger than the cross-cultural one Jones and Hill, 1993 and Perrett et al., 1998. On the other hand, adults may, by virtue of their greater overall experience with all kinds of faces and because of more efficient encoding strategies Carey, 1992 and Ellis and Flin, 1990, perceive a greater variability of attractiveness in both adults’ and children’s faces. In order to investigate the invariance of preference strength across age groups and the influence of stimulus type on such preference strength we used a method that allows us to look at preference differences more closely than the commonly used comparison of pre-rated stimulus categories (attractive versus unattractive) allows for. We report the results of an experiment where subjects of three different age groups (nine-year-olds, twelve-year-olds, adults) were presented with two series of pairs of faces (women’s faces and girls’ faces). Facial attractiveness was measured using the traditional pair comparison method Luce, 1959, Thurstone, 1927 and Suppes et al., 1989 rather than the currently more commonly used rating method Bäuml et al., 1997, Meerdink et al., 1990 and Rhodes and Tremewan, 1996. The pair comparison method provides a very simple task for subjects. Subjects do not need to assign numbers to faces such that these numbers directly reflect the perceived attractiveness of the faces, but merely have to indicate which of two faces is more attractive. This feature of simplicity makes the method particularly suitable for investigating children’s perception of attractiveness. Moreover, preference strengths can be directly compared across groups, allowing for a more detailed insight into the structure of childrens’ and adults’ preferences than previously available. When pooled over the subjects of an age group, the pair comparisons result in a set of preference frequencies for each age group. These frequencies can then be used to construct simple, theoretically well-founded scales that permit meaningful statements about the ratios of the attractiveness scores of single faces. These ratios can then be compared across age groups, thus providing information on how the perception of facial attractiveness varies with the beholder’s age. The general feasibility of such a scaling of the attribute facial attractiveness has been shown previously (Bäuml, 1994), although the present experiment is the first one of this type with children. We therefore chose children of an age at which we could be quite confident that they would understand the instruction, be well able to sit through the session, and display a considerable degree of interrater reliability (Cavior & Lombardi, 1973). In order to exclude gender of the beholder or gender of stimulus face as possible confounding factors (Meerdink et al., 1990), only female subjects participated in the experiment and only female faces were used as stimuli.