Article Evaluation

Research Article

Nature andNurture in Own-Race Face Processing Yair Bar-Haim,1 Talee Ziv,1 Dominique Lamy,1 and Richard M. Hodes2

1Department of Psychology, Tel-Aviv University, Tel-Aviv, Israel, and 2American Jewish Joint Distribution Committee,

Addis Ababa, Ethiopia

ABSTRACT—A standard visual preference task was used to

examine 3-month-olds’ looking times at own-race versus

other-race faces as a function of environmental exposure

to faces from the two categories. Participants were Cau-

casian infants living in a Caucasian environment, African

infants living in an African environment, and African in-

fants living in a predominantly Caucasian environment.

The results indicate that preference for own-race faces is

present as early as 3months of age, but that this preference

results from exposure to the prototypical facial environ-

ment.

Intergroup bias is the systematic tendency to evaluate members

of one’s own group (the in-group) more favorably than members

of a group to which one does not belong (the out-group). This

tendency can take the form of favoring in-group members, der-

ogating out-groupmembers, or both (Hewstone, Rubin, &Willis,

2002). Intergroup bias is thought to be an initial form of preju-

dice that is based on a fundamental strategy for survival and

personal well-being in the context of group living (Brewer,

2001). A salient instance of intergroup bias is racial prejudice.

Several researchers have suggested that differential pro-

cessing of the characteristic features of own-race versus other-

race members may contribute to prejudice and stereotyping

(e.g., Aboud, 1988; Bigler & Liben, 1993; Doyle & Aboud,

1995; Katz, 2003; MacLin & Malpass, 2001; Richeson &

Shelton, 2003). For example, people are more accurate at rec-

ognizing faces from their own racial group than faces from other

races (for reviews and discussion, see Bothwell, Brigham, &

Malpass, 1989; Meissner & Brigham, 2001). A recent functional

magnetic resonance imaging study by Golby, Gabrieli, Chiao,

and Eberhardt (2001) provided evidence that this recognition

bias is accompanied by a race-dependent neural activation

pattern. Using a recognition paradigm, these authors found

higher activation in response to own-race than to other-race

faces in specific face-sensitive regions of the adult brain.

By the age of 4 to 6 years, children already display racial

stereotyping and prejudice in a variety of contexts (e.g., Aboud,

2003; Doyle & Aboud, 1995; Katz, 2003; Killen, Lee-Kim,

McGlothlin, & Stangor, 2002). At about the same age, children

also display a recognition advantage for own-race faces. Fein-

man and Entwisle (1976) tested Caucasian and African Amer-

ican children in Grades 1, 2, 3, and 6 on their ability to recognize

photographs of Caucasian and African American children.

Performance improved significantly with age, but the same own-

race bias was evident at each age for both African Americans

and Caucasians (see also Pezdek, Blandon-Gitlin, & Moore,

2003, for similar findings in third graders, and Sangrigoli & de

Schonen, 2004a, for a study of 3- to 5-year-old Caucasians tested

for recognition of Caucasian and Oriental faces).

Evidence for an own-race processing bias in early infancy has

also been reported. In a study on the development of racial

prejudice in young infants, Katz and Downey (2002, cited in

Katz, 2003) used a habituation-dishabituation paradigm to test

6-month-olds’ ability to discriminate between own-race and

other-race faces and showed what may be an early reflection of

other-race homogenization. Caucasian infants’ response to a

Caucasian male face after being habituated to four Caucasian

female faces was stronger than their response to an African

American male face after being habituated to four African

American female faces. For African American infants, the

findings were reversed. The greater ease of responding to gender

cues with own-race than other-race faces suggests that differ-

ential processing of own-race versus other-race faces occurs

very early on. Recently, Sangrigoli and de Schonen (2004b)

assessed the own-race recognition bias in 3-month-old Cauca-

sians. Infants were first habituated to a single face. Then, at test,

the same face was presented together with a novel face of the

same race. Looking times at the novel face were longer for

Caucasian than for Asiatic faces, suggesting that the infants

were better at recognizing own-race than other-race faces.

Address correspondence to Yair Bar-Haim, Department of Psychol- ogy, Tel-Aviv University, Ramat Aviv, Tel-Aviv 69978, Israel, e-mail: [email protected].

PSYCHOLOGICAL SCIENCE

Volume 17—Number 2 159Copyright r 2006 Association for Psychological Science

One explanation for the own-race processing advantage is that

people tend to have more contact with multiple face exemplars

from their own race than from other races and therefore develop

expertise at recognizing own-race faces (Brigham & Barkowitz,

1978; Brigham & Malpass, 1985; Gauthier & Nelson, 2001;

Malpass & Kravitz, 1969; Nelson, 2001). Evidence for this

contact, or differential-experience, hypothesis comes from stud-

ies showing reduced deficits in other-race face recognition in

members of minority groups. For example, in the United States,

the same-race recognition advantage is greater for Caucasians

than for African Americans (e.g., Anthony, Copper, & Mullen,

1992; Golby et al., 2001), who, by virtue of being aminority, tend

to have more contact with people of other races than Caucasians

do. This asymmetry has also been demonstrated in children.

Feinman and Entwisle (1976) showed that African American

children were better at recognizing Caucasian faces than Cau-

casian children were at recognizing African American faces.

Furthermore, children who came from integrated schools and

lived in mixed-race neighborhoods showed smaller biases than

children from segregated schools. Other results showing that

training and exposure reduce the other-race effect also support

the differential-experience hypothesis (Elliott, Wills, & Gold-

stein, 1973; Goldstein & Chance, 1985; Lavrakas, Buri, &

Mayzner, 1976; Li, Dunning, & Malpass, 1998). Remarkably,

Sangrigoli and de Schonen (2004b, Study 2) showed that the

own-race recognition bias was eliminated when infants under-

went a familiarization phase in which they were exposed to only

three exemplars of other-race faces.

In the context of the study of the development of racial prej-

udice, however, it is important to examine whether young infants

show an actual preference, rather than a processing advantage,

for members of their own race. Although differential processing

of own-race versus other-race faces may indeed be associated

with own-race favoritism, that is not necessarily the case.

The infant studies that demonstrated an own-race processing

advantage (Sangrigoli & de Schonen, 2004b), or in one instance

an own-species processing advantage (Pascalis, de Haan, &

Nelson, 2002), used paradigms that rely on infants’ response to

novelty following habituation. In these paradigms, longer looking

times at a novel face are taken to demonstrate infants’ catego-

rization and discrimination abilities. These abilities were found

to be superior for own-race or own-species faces relative to

other-race or other-species faces. Such habituation-dishabitua-

tion procedures, however, do not allow one to draw inferences

about preference for own-race faces, because own-race and

other-race faces do not compete for infants’ attention and interest.

Instead, there is competition between a novel face and a habit-

uated face of the same race, and the magnitude of the resulting

novelty effect is compared between own-race and other-race

faces. In contrast, standard visual preference tasks can provide

evidence for own-race preference. When exemplars of two racial

categories are presented simultaneously, and thus compete for

an infant’s interest, preference can be inferred if the infant

consistently looks longer at one category (e.g., African faces) than

at the other (e.g., Caucasian faces). Differential looking has been

used similarly in the attractiveness literature as a measure of

discrimination and preference (e.g., Langlois, Ritter, Roggman,

& Vaughn, 1991; Rubenstein, Kalakanis, & Langlois, 1999).

The purpose of the present research was to assess whether

infants as young as 3 months of age show preference for own-

race faces relative to other-race faces, and whether the develop-

ment of such preference is modulated by infants’ exposure to

members of other races in the immediate social environment. To

that end, we used a standard visual preference task to examine

3-month-olds’ visual preferences for own-race versus other-race

faces as a function of environmental exposure to faces from the

two categories.

METHOD

Participants

Participants were 36 healthy full-term infants, selected from

three distinct populations with different degrees of contact with

members of other races. Six additional infants were tested, but

did not complete the experiment because of fussiness. Each

group consisted of 12 infants (6 male, 6 female). The Caucasian

Israeli group (mean age 5 14.08 weeks, SD 5 1.44) was re-

cruited from the general population of Israel and lived in a pri-

marily Caucasian environment. The African Ethiopian group

(mean age 5 13.67 weeks, SD 5 1.72) was recruited from

families living in Addis Ababa and Gonder, Ethiopia, and

awaiting immigration to Israel; these families lived in a primarily

African environment. The African Israeli group (mean age 5

13.75 weeks, SD 5 1.54) consisted of Israeli-born infants of

Ethiopian origin. The African Israeli group was recruited from

Ethiopian families who were new immigrants to Israel living in

absorption centers. Many new immigrants’ first home in Israel is

an absorption center, where they live for 6 to 18 months. Such

centers provide intensive cross-race contact for new immigrants

from Ethiopia. Because the centers provide a vast array of social

support and acculturation services, the primarily Caucasian staff

running them is in close, daily contact with the resident families

and their children. For instance, infants living in the absorption

centers undergo routine bimonthly examinations by Caucasian

Well Child Service providers. Additional cross-race exposure

results from the fact that new Caucasian immigrants (primarily

from Argentina and countries of the former Soviet Union) also

reside in the same absorption centers. Finally, only 1% of the

general population in Israel is of Ethiopian origin. Thus, when-

ever the African Israeli infants were taken outside the absorption

center, they were heavily exposed to members of another race.

Stimuli

Each stimulus display consisted of color photographs of two

faces (8 cm � 9.6 cm) presented side by side against a gray

160 Volume 17—Number 2

Nature and Nurture in Face Processing

background. The nearest edges of the two photographs were 6 cm

apart. A set of eight different face pairs was generated. Each pair

consisted of one Caucasian face and one African (Ethiopian)

face that was of the same sex and matched for attractiveness (see

Fig. 1a for examples of the face stimuli used).Within this set, the

African face appeared on the right and the Caucasian face on the

left for four pairs (two male, two female), and the left-right po-

sition was reversed for the remaining four pairs. The 16 photo-

graphs used in the experiment were selected from a larger

collection of African and Caucasian faces rated for attractive-

ness on a 5-point scale by Caucasian Israeli, African Israeli, and

African Ethiopian adults. The mean age of the models in the

selected set was 22.06 years (SD 5 4.10), and the mean at-

tractiveness was 2.54 (SD 5 0.63). All faces were frontally

oriented and displayed a neutral expression. Clothing cues were

masked. Each infant viewed the set of eight face pairs once.

Order of the pairs was randomized separately for each infant.

Procedure

The experiment was conducted in small, darkened rooms. The

infants were seated on their mothers’ laps with their heads po-

sitioned about 30 cm from a 14-in. laptop computer screen that

was used for stimulus presentation. A portable one-way mirror

served as a partition between the experimenter and the infant.

Mothers were instructed to fixate on a mark above their heads.

Thus, they could not see the face stimuli, which ensured that

their preferences could not be communicated to the infants.

Before the beginning of each trial, a series of black-and-white

visual patterns and click noises was presented to draw the in-

fant’s gaze to the center of the screen. As soon as this happened,

the experimenter, who observed the infant’s visual fixations from

behind the one-way mirror, initiated the trial, and a face pair

appeared for 10 s. The experimenter recorded on-line, on a

second laptop computer, the direction of each gaze (right, left,

not focused) and its duration (in seconds). The experimenter

could not see the stimuli that the infant was viewing and was thus

blind as to what type of face appeared on each side of the

computer screen at any given time. Interrater reliability was

assessed in a pilot study involving 29 Israeli infants. Mean

percentage agreement was 97%.

RESULTS

The results are summarized in Figure 1b. A repeated measures

analysis of variance (ANOVA) on average looking times (in

seconds) with group (Caucasian Israeli, African Ethiopian, or

African Israeli) as a between-subjects variable and face type

(Caucasian or African) and face gender (male or female) as

within-subjects variables revealed a significant Group � Face Type interaction, F(2, 33) 5 5.34, p < .01. A trend toward a

main effect of group was also found, F(2, 33)5 2.79, p5 .076;

average total looking times were 7.47, 6.07, and 7.86 s (SDs 5

1.43, 1.78, and 2.41), for the Caucasian Israeli, African Ethio-

pian, and African Israeli groups, respectively. The main effect of

face type was nonsignificant ( p 5 .13), and so were all the ef-

fects involving gender of the face (all ps > .40).

To explicate the Group � Face Type interaction, we con- ducted three separate ANOVAs, one for each pair of groups.

Because no main effect of face gender and no interactions in-

volving this factor were found, it was omitted from further

analyses. A significant Group � Face Type interaction was found in the analysis of the Caucasian Israeli and African

Ethiopian infants,F(1, 22)5 17.36, p< .001, Cohen’s d5 1.78.

Fig. 1. Examples of the face stimuli (a) and looking times (in seconds) of the Caucasian Israeli, African Ethiopian, and African Israeli infants. Whiskers represent standard errors.

Volume 17—Number 2 161

Y. Bar-Haim et al.

The Group � Face Type interactions only approached signifi- cance for the comparisons between the Caucasian Israeli and

African Israeli infants and between the African Israeli and Af-

rican Ethiopian infants,Fs(1, 22)5 2.72 and 1.69, ps5 .06 and

.10, Cohen’s ds 5 0.70 and 0.56, respectively.

In addition, we assessed the effect of face type separately for

each group. These analyses showed that the Caucasian Israeli

infants looked longer at Caucasian than at African faces, paired

two-tailed t test, t(11) 5 3.40, p < .01, Cohen’s d 5 1.03. In

contrast, African Ethiopian infants looked longer at African than

at Caucasian faces, paired two-tailed t test, t(11) 5 2.56, p <

.05, Cohen’s d 5 0.77. Remarkably, Israeli-born infants of

Ethiopian origin showed no particular preference for African or

Caucasian faces, paired two-tailed t test, t(11)5 0.50, p5 .63,

Cohen’s d5 0.15. A power analysis, calculating for 50% power,

revealed that at least 301 additional participants would have

been required in order to obtain a significant preference for

Caucasian faces in this group. We therefore conclude that the

null result obtained for the African Israeli group is reliable.

To ensure that these results indeed reflected a preference for

own-race faces rather than culturally mediated color prefer-

ences, we carried out a control study among 3-month-old Cau-

casian Israeli (5 girls, 7 boys) and African Ethiopian (6 girls, 6

boys) infants living in Israel and in Ethiopia, respectively. The

procedure was similar to that of themain experiment, except that

all the faces of each race were replaced by a colored patch

matching their average color composition. Thus, each Cauca-

sian face was replaced by a uniform pink oval patch (RGB co-

ordinates 5 220, 190, 180), whereas each Ethiopian face was

replaced by a brown oval patch (RGB coordinates5 90, 65, 70).

We reasoned that if color rather than race-related preferences

were at play in the main experiment, the same results would be

observed.

Overall, infants showedmuch less interest in the colored ovals

(mean total looking duration at both the pink and brown ovals5

2.63 s, SD5 1.53) than in the human faces (mean total looking

duration at both the African and Caucasian faces5 7.11 s, SD5

2.02). More important, however, the results showed no specific

color preference in either of the two groups, paired two-tailed

t tests, ts(11)5 0.73 and 1.03, ps5 .48 and .33, for Caucasian

Israeli and African Ethiopian infants, respectively. These find-

ings allow us to conclude that the results of the main experiment

indeed reflected a bias in favor of own-race faces, rather than

simple color preferences.

DISCUSSION

In the present study, the looking-time patterns of the Caucasian

Israeli and African Ethiopian groups were race dependent. This

finding indicates that by 3months of age, infants have the ability

to discriminate between own-race and other-race adult faces and

is consistent with previous habituation-dishabituation studies,

in which such abilities have been observed in 3- and 6-month-

olds (Katz & Downey, 2002; Sangrigoli & de Schonen, 2004b).

However, although the ability to categorize faces on the basis of

characteristic racial features may be a prerequisite for the de-

velopment of own-race favoritism, it is clearly not a sufficient

condition for such favoritism. In this respect, the present study is

novel in showing that actual preference for own-race faces may

be present as early as 3 months of age.

The results also underscore the prominent role of infants’

racial environment in the development of this preference for

own-race faces. Indeed, preference for own-race faces was ob-

served only in infants living in predominantly homogeneous

own-race environments, and not in infants who experienced

intensive cross-race exposure. Unlike Caucasian Israeli and

African Ethiopian infants who live within an own-race majority

and develop a clear preference for own-race faces, African Is-

raeli infants (who by virtue of being a very small ethnic minority

experience considerable cross-race exposure) do not develop a

preference for own-race faces. Note that whereas earlier studies

showed a smaller but nonetheless significant other-race effect

in the African American minority relative to the Caucasian

American majority (e.g., Golby et al., 2001), our African Israeli

sample showed no preference. Although there are numerous

differences between the American studies and ours (e.g., chil-

dren and adults vs. infants, recognition vs. preference task), this

discrepancy is likely the result of more intensive cross-race

exposure in our sample (e.g., African Americans make up ap-

proximately 15% of the American population, whereas African

Israelis make up only 1% of the Israeli population). An expla-

nation based on cross-race contact is also consistent with find-

ings that studying in integrated schools and living in mixed-race

environments further reduce the own-race recognition bias in

African American children (Feinman & Entwisle, 1976), and

with Sangrigoli and de Schonen’s (2004b, Study 2) finding that

the own-race recognition bias in 3-month-olds disappears with

very little exposure to other-race faces.

A recent study by Sangrigoli, Pallier, Argenti, Ventureyra, and

de Schonen (2005) further underscores the role of the environ-

ment in shaping the own-race bias by showing that early in-

tensive contact with other-race faces can overturn the bias.

Sangrigoli et al. found that adults of Korean origin who were

adopted by European Caucasian families between the ages of 3

and 9 years identified Caucasian faces better than Asian faces.

It is noteworthy, however, that in earlier studies on the own-

race bias in children (e.g., Feinman & Entwisle, 1976; San-

grigoli & de Schonen, 2004b; Sangrigoli et al., 2005), the pre-

dominant racial environment was always Caucasian, and was

therefore not counterbalanced between races. By investigating

the role of exposure to a dominant own-race environment versus

a dominant other-race environment in different racial contexts

(Caucasian and African), the present study provides an impor-

tant validation for the idea that the development of the own-race

bias is modulated by exposure to a homogeneous own-race facial

environment.

162 Volume 17—Number 2

Nature and Nurture in Face Processing

Early preferences for own-race faces may contribute to race-

related biases later in life, perhaps by facilitating cognitive and

emotional processing of own-race faces. Longitudinal data

would be necessary to examine this hypothesis, that is, to in-

vestigate potential links between infants’ preferences for own-

race faces and own-race favoritism or prejudice later in child-

hood. Although the present findings indicate that preference for

own-race faces emerges out of very early exposure to prototyp-

ical perceptual environments, they also demonstrate that sig-

nificant exposure to other-race faces can block the development

of own-race preference. Sangrigoli and de Schonen (2004b)

showed that the recognition bias present in 3-month-old infants

can be eliminated with very brief exposure to other-race faces.

We speculate that the same might hold true for preference for

own-race faces. An important goal for further research would be

to delineate the critical period during which early-formed

preferences for own-race faces may be altered by exposure to

other-race faces.

Acknowledgments—This study was partially supported by The

Israeli Science Foundation (Grant No. 989/03).

REFERENCES

Aboud, F.E. (1988). Children and prejudice. New York: Blackwell. Aboud, F.E. (2003). The formation of in-group favoritism and out-group

prejudice in young children: Are they distinct attitudes? Devel- opmental Psychology, 39, 48–60.

Anthony, T., Copper, C., & Mullen, B. (1992). Cross-racial facial

identification: A social cognitive integration. Personality and Social Psychology Bulletin, 18, 296–301.

Bigler, R.S., & Liben, L.S. (1993). A cognitive–developmental ap-

proach to racial stereotyping and reconstructive memory in Euro-

American children. Child Development, 64, 1507–1508. Bothwell, R.K., Brigham, J.C., & Malpass, R.S. (1989). Cross-racial

identification. Personality and Social Psychology Bulletin, 15, 19–25.

Brewer, M.B. (2001). Ingroup identification and intergroup conflict:

When does ingroup love become outgroup hate? In R.D. Ashmore,

L. Jussim, & D. Wilder (Eds.), Social identity, intergroup conflict, and conflict reduction (pp. 17–41). London: Oxford University Press.

Brigham, J.C., & Barkowitz, P. (1978). Do ‘‘They all look alike’’? The

effect of race, sex, experience, and attitudes on the ability to

recognize faces. Journal of Applied Social Psychology, 8, 306–318. Brigham, J.C., & Malpass, R.S. (1985). The role of experience and

contact in the recognition of faces of own- and other-race persons.

Journal of Social Issues, 41, 139–155. Doyle, A.B., & Aboud, F.E. (1995). A longitudinal study of White

children’s racial prejudice as a social cognitive development.

Merrill Palmer Quarterly, 41, 209–228. Elliott, E.S., Wills, E.J., & Goldstein, A.G. (1973). The effects of dis-

crimination training on the recognition of White and Oriental

faces. Bulletin of the Psychonomic Society, 2, 71–73. Feinman, S., & Entwisle, D.R. (1976). Children’s ability to recognize

other children’s faces. Child Development, 47, 506–510. Gauthier, I., & Nelson, C.A. (2001). The development of face expertise.

Current Opinion in Neurobiology, 11, 219–224.

Golby, A.J., Gabrieli, J.D.E., Chiao, J.Y., & Eberhardt, J.L. (2001).

Differential responses in the fusiform region to same-race and

other-race faces. Nature Neuroscience, 4, 845–850. Goldstein, A.G., & Chance, J.E. (1985). Effects of training on Japanese

face recognition: Reduction of the other-race effect. Bulletin of the Psychonomic Society, 23, 211–214.

Hewstone, M., Rubin, M., & Willis, H. (2002). Intergroup bias. Annual Review of Psychology, 53, 575–604.

Katz, P.A. (2003). Racist or tolerant multiculturalists? How do they

begin? American Psychologist, 58, 897–909. Katz, P.A., & Downey, E.P. (2002). Infant categorization of race and

gender cues. Unpublished manuscript, Institute for Research on Social Problems, Boulder, CO.

Killen, M., Lee-Kim, J., McGlothlin, H., & Stangor, C. (2002). How

children and adolescents evaluate gender and racial exclusion.

Monographs of the Society for Research in Child Development, 67(4, Serial No. 271).

Langlois, J.H., Ritter, J.M., Roggman, L.A., & Vaughn, L.S. (1991).

Facial diversity and infant preferences for attractive faces. De- velopmental Psychology, 27, 79–84.

Lavrakas, P.J., Buri, J.R., &Mayzner, M.S. (1976). A perspective on the

recognition of other-race faces. Perception & Psychophysics, 20, 475–481.

Li, J.C., Dunning, D., & Malpass, R.S. (1998). Cross-racial identifica- tion among European-Americans: Basketball fandom and the contact hypothesis. Unpublished manuscript, Cornell University, Ithaca, NY.

MacLin, O.H., & Malpass, R.S. (2001). Racial categorization of faces:

The ambiguous race face effect. Psychology, Public Policy, and Law, 7, 98–118.

Malpass, R.S., &Kravitz, J. (1969). Recognition for faces of own and other

race. Journal of Personality and Social Psychology, 13, 330–334. Meissner, C.A., & Brigham, J.C. (2001). Thirty years of investigating

the own-race bias in memory for faces: A meta-analytic review.

Psychology, Public Policy, and Law, 7, 3–35. Nelson, C.A. (2001). The development and neural bases of face rec-

ognition. Infant and Child Development, 10, 3–18. Pascalis, O., de Haan, M., & Nelson, C.A. (2002). Is face processing

species-specific during the first year of life? Science, 296, 1321– 1323.

Pezdek, K., Blandon-Gitlin, I., & Moore, C. (2003). Children’s face

recognition memory: More evidence for the cross-race effect.

Journal of Applied Psychology, 88, 760–763. Richeson, J.A., & Shelton, J.N. (2003). When prejudice does not pay:

Effects of interracial contact on executive function. Psychological Science, 14, 287–290.

Rubenstein, A.J., Kalakanis, L., & Langlois, J.H. (1999). Infant pref-

erences for attractive faces: A cognitive explanation. Develop- mental Psychology, 35, 848–855.

Sangrigoli, S., & de Schonen, S. (2004a). Effect of visual experience

on face processing: A developmental study of inversion and non-

native effects. Developmental Science, 7, 74–87. Sangrigoli, S., & de Schonen, S. (2004b). Recognition of own-race and

other-race faces by three-month-old infants. Journal of Child Psychology and Psychiatry and Allied Disciplines, 45, 1219–1227.

Sangrigoli, S., Pallier, C., Argenti, A.-M., Ventureyra, V.A.G., & de

Schonen, S. (2005). Reversibility of the other-race effect in face

recognition during childhood.Psychological Science, 16, 440–444.

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