Categorization,categorical perception,and asymmetry in infants’ representation of face race

The present study examined whether 6‐ and 9‐month‐old Caucasian infants could categorize faces according to race. In Experiment 1, infants were familiarized with different female faces from a common ethnic background (i.e. either Caucasian or Asian) and then tested with female faces from a novel race category. Nine‐month‐olds were able to form discrete categories of Caucasian and Asian faces. However, 6‐month‐olds did not form discrete categories of faces based on race. In Experiment 2, a second group of 6‐ and 9‐month‐olds was tested to determine whether they could discriminate between different faces from the same race category. Results showed that both age groups could only discriminate between different faces from the own‐race category of Caucasian faces. The findings of the two experiments taken together suggest that 9‐month‐olds formed a category of Caucasian faces that are further differentiated at the individual level. In contrast, although they could form a category of Asian faces, they could not discriminate between such other‐race faces. This asymmetry in category formation at 9 months (i.e. categorization of own‐race faces vs. categorical perception of other‐race faces) suggests that differential experience with own‐ and other‐race faces plays an important role in infants’ acquisition of face processing abilities.     

Infant preference for female faces occurs for same‐ but not other‐race faces

There has been a recent surge of interest in the question of how infants respond to the social attributes of race and gender information in faces. This work has demonstrated that by 3 months of age, infants will respond preferentially to same‐race faces and faces depicting the gender of the primary caregiver. In the current study, we investigated emergence of the female face preference for same‐ versus other‐race faces to examine whether the determinants of preference for face gender and race are independent or interactive in young infants. In Expt 1, 3‐month‐old Caucasian infants displayed a preference for female over male faces when the faces were Caucasian, but not when the faces were Asian. In Expt 2, new‐born Caucasian infants did not demonstrate a preference for female over male faces for Caucasian faces. The results are discussed in terms of a face prototype that becomes progressively tuned as it is structured by the interaction of the gender and race of faces that are experienced during early development.     

Narrowing in categorical responding to other‐race face classes by infants

Infants can form object categories based on perceptual cues, but their ability to form categories based on differential experience is less clear. Here we examined whether infants filter through perceptual differences among faces from different other‐race classes and represent them as a single other‐race class different only from own‐race faces. We used a familiarization/novelty‐preference procedure to investigate category formation for two other‐race face classes (Black vs. Asian) by White 6‐ and 9‐month‐olds. The data indicated that while White 6‐month‐olds categorically represented the distinction between Black and Asian faces, White 9‐month‐olds formed a broad other‐race category inclusive of Black and Asian faces, but exclusive of own‐race White faces. The findings provide evidence that narrowing can occur for mental processes other than discrimination: category formation is also affected. The results suggest that frequency of experience with own‐race versus other‐race classes of faces may propel infants to contrast own‐race faces with other‐race faces, but not different classes of other‐race faces with each other.     

Task‐irrelevant own‐race faces capture attention: Eye‐tracking evidence

To investigate attentional capture by face’s race, the current study recorded saccade latencies of eye movement measurements in an inhibition of return (IOR) task. Compared to Caucasian (other‐race) faces, Chinese (own‐race) faces elicited longer saccade latency. This phenomenon disappeared when faces were inverted. The results indicated that own‐race faces capture attention automatically with high‐level configural processing.     

The influence of social factors and implicit racial bias on a generalized own‐race effect

The current study sought to determine whether the experimentally reported ‘own‐race effect’ is other‐race specific, or whether it is a generalized effect. The perceptual processing of own‐ versus two groups of other‐race faces was therefore explored in White and South Asian individuals. Participants completed a computer‐based discrimination task of White, South Asian and Black face‐morphs. Results showed a generalized own‐race effect for White and South Asian participants discriminating own‐ versus other‐race (White/South Asian and Black) faces, such that individuals demonstrated a perceptual discrimination advantage for own‐ versus other‐race faces in general. These findings were linked to implicit racial bias and other‐race individuating experience, demonstrating that social variables play an important role in the magnitude of the own‐race effect. Copyright © 2007 John Wiley & Sons, Ltd.     

Holistic face encoding is modulated by perceived face race: Evidence from perceptual adaptation

Human expertise at processing faces relies on how facial features are encoded: as a whole template rather than as a sum of independent features. This holistic encoding is less prominent for other-race faces, possibly accounting for the difficulty one encounters in recognizing these faces (the ‘other-race effect’). Here, we tested the hypothesis that the magnitude of holistic face encoding can be modulated by racial categorization of the face. Caucasian participants performed a face-composite task with ‘racially-ambiguous’ face-stimuli (cross-race morphed faces, equally categorized as Asian or Caucasian faces in an independent task). The perceived race of the ambiguous faces was manipulated using adaptation. Experiment 1 showed that identical morphed face-stimuli were processed more holistically when perceived as ‘same-race’ than as ‘other-race’, i.e., following adaptation to ‘other-race’ versus ‘same-race’, respectively. Experiment 2 ascertained that the determining factor in the observed holistic processing modulation was the race of the racially-ambiguous face as perceived, rather than expected, by the participants, which supports the idea that the holistic processing of the face-stimuli was modulated by their race-categorization at the perceptual level.     

The development of preferences for own-race versus other-race faces in 3-, 6- and 9-month-old Caucasian infants

Visual preferences for pairs of African and Caucasian faces were repeatedly assessed in 3-, 6- and 9-month-old Caucasian infants with a preferential looking paradigm. Two different patterns of preference development were found: First, the spontaneous own-race preference at three months reported in the literature tilts to a preference for other-race faces at nine months passing through a null-preference at six months. This replicates the pattern recently reported for Asian infants [Liu et al. (2015). Development of visual preference for own- versus other-race faces in infancy. Developmental Psychology. doi:10.1037/a0038835]. Second, at all three ages fixation time towards Caucasian faces significantly reduces across the consecutive trial presentation. This is a similar effect as in novelty preference studies to occur after a sufficiently long familiarization phase. Both patterns can be explained in terms of an advantaged own-race face processing with the emerging Other-Race-Effect.     

知觉适应对种族融合面孔的种族分类和知觉辨别的影响

面孔加工的种族效应(the other-race effects)指人们对面孔做个体辨别任务时辨别本族面孔的绩效优于辨别他族面孔的绩效, 而做种族分类任务时分类他族面孔的绩效优于分类本族面孔的绩效。本研究通过知觉适应操纵被试对种族两歧(高加索和亚洲)融合面孔的种族知觉, 进而比较被试在两种条件下对同一张融合面孔进行种族分类和知觉辨别的绩效的差异。结果发现, 知觉适应能使被试产生将两歧融合面孔知觉为与原始面孔所属种族相反种族的知觉偏向, 并且, 伴随着这种知觉偏向, 两歧融合面孔的加工出现了他族分类优势和本族辨别优势, 提示社会认知因素对面孔加工的种族效应有重要作用。     

Association Learning with Own‐ and Other‐race Faces in three‐ and six‐month old infants – A longitudinal study

This longitudinal study assessed 133 Caucasian German infants at 3 and 6 months of age to investigate the influence of own‐race and other‐race faces as visual stimuli on association learning in the visual expectation paradigm (VExP). The study is related to the findings on the other‐race‐effect (ORE) which is said to emerge at 6 months of age. Caucasian faces were used as stimuli of a familiar ethnic category, whereas African faces were used as stimuli of an unfamiliar ethnic category. There was no significant difference between the two stimulus classes in infants' reaction time (RT) to stimulus shifts at 3 months. At 6 months of age, infants' RT decreased significantly in the Caucasian faces condition but not in the African faces condition. These results indicate that the processing of other‐race versus own‐race faces by the age of 6 months, which is also the relevant age for the onset of the ORE, has an important influence on the performance on the VExP. Copyright © 2011 John Wiley & Sons, Ltd.     

The flip side of the other‐race coin: They all look different to me

Poorer recognition of other‐race faces than own‐races faces has been attributed to a problem of discrimination (i.e., telling faces apart). The conclusion that ‘they all look the same to me' is based on studies measuring the perception/memory of highly controlled stimuli, typically involving only one or two images of each identity. We hypothesized that such studies underestimate the challenge involved in recognizing other‐race faces because in the real world, an individual's appearance varies in a number of ways (e.g., lighting, expression, hairstyle), reducing the utility of relying on pictorial cues to identity. In two experiments, Caucasian and East Asian participants completed a perceptual sorting task in which they were asked to sort 40 photographs of two unfamiliar identities into piles such that each pile contained all photographs of a single identity. Participants perceived more identities when sorting other‐race faces than own‐race faces, both when sorting celebrity (Experiment 1) and non‐celebrity (Experiment 2) faces, suggesting that in the real world, ‘they all look different to me'. We discuss these results in the light of models in which each identity is represented as a region in a multidimensional face space; we argue that this region is smaller for other‐race than own‐race faces.     

Novelty and frequency as determinants of newborn preference

The debate over whether infants prefer a familiar stimulus over a novel stimulus has persisted for over 30 years, and there is evidence which supports both sides of the question. However, the research which supports the preference for the familiar uses different measures than that which supports the preference for novelty. In the first experiment, the preference for the familiar was tested by making one stimulus more familiar than the others presented. A target of a ‘familiar’ face was presented eight times more frequently than the other faces. During the experiment, the infants could choose at which face they looked and for how long. It was found that the infants significantly preferred the familiar face over any one of the novel faces, especially when the familiar face was presented first. Substituting auditory for visual stimuli, the second experiment was a replication of the first experiment. Consonant–vowel syllables were used instead of faces. Overall, 17 stimuli were used: one repeating ‘familiar’ sound, and 16 novel sounds. It was found that the infants significantly preferred the familiar sound over any of the novel sounds. As found in Experiment 1, the infants also had a greater preference for the familiar sound when it was presented first.     

Similarity and difference in the processing of same- and other-race faces as revealed by eye tracking in 4- to 9-month-olds

Fixation duration for same-race (i.e., Asian) and other-race (i.e., Caucasian) female faces by Asian infant participants between 4 and 9 months of age was investigated with an eye-tracking procedure. The age range tested corresponded with prior reports of processing differences between same- and other-race faces observed in behavioral looking time studies, with preference for same-race faces apparent at 3 months of age and recognition memory differences in favor of same-race faces emerging between 3 and 9 months of age. The eye-tracking results revealed both similarity and difference in infants’ processing of own- and other-race faces. There was no overall fixation time difference between same race and other race for the whole face stimuli. In addition, although fixation time was greater for the upper half of the face than for the lower half of the face and trended higher on the right side of the face than on the left side of the face, face race did not impact these effects. However, over the age range tested, there was a gradual decrement in fixation time on the internal features of other-race faces and a maintenance of fixation time on the internal features of same-race faces. Moreover, the decrement in fixation time for the internal features of other-race faces was most prominent on the nose. The findings suggest that (a) same-race preferences may be more readily evidenced in paired comparison testing formats, (b) the behavioral decline in recognition memory for other-race faces corresponds in timing with a decline in fixation on the internal features of other-race faces, and (c) the center of the face (i.e., the nose) is a differential region for processing same- versus other-race faces by Asian infants.     

A perceptual discrimination investigation of the own‐race effect and intergroup experience

Research over the past two decades has demonstrated that individuals are better at the recognition and discrimination of own‐ versus other‐race faces. Recent evidence, however, supports an own‐race effect at the level of perceptual encoding in adults. The current study examines the perceptual basis of the own‐race effect in secondary students from two racially segregated communities (White and South Asian). The contact hypothesis is investigated, as other‐race experience may influence other‐race face perception. Face stimuli were generated by morphing together South Asian and White faces along a linear continuum. In a same/different perceptual discrimination task participants judged whether face stimuli were physically identical to, or different from, the original faces. Results revealed a significant own‐race effect for the White participants only, wherein they were better at discriminating White relative to South Asian faces. Other‐race individuating experience was found to predict the own‐race effect, indicating that other‐race experience influences other‐race face perceptual expertise. Copyright © 2006 John Wiley & Sons, Ltd.     

Race-based perceptual asymmetries underlying face processing in infancy

Adults process other-race faces differently than own-race faces. For instance, a single other-race face in an array of own-race faces attracts Caucasians’ attention, but a single own-race face among other-race faces does not. This perceptual asymmetry has been explained by the presence of an other-race feature in other-race faces and its absence in own-race faces; this difference is thought to underlie race-based differences in face processing. We examined the developmental origins of this mechanism in two groups of Caucasian 9-month-olds. Infants in the experimental group exhibited a preference for a pattern containing a single Asian face among seven Caucasian faces over a pattern containing a single Caucasian face among seven Asian faces. This preference was not driven by the majority of elements in the images, because a control group of infants failed to exhibit a preference between homogeneous patterns containing eight Caucasian versus eight Asian faces. The results demonstrate that an other-race face among own-race faces attracts infants’ attention but not vice versa. This perceptual asymmetry suggests that the other-race feature is available to Caucasians by 9 months of age, thereby indicating that mechanisms of specialization in face processing originate early in life.     

知觉经验对面孔整体加工的影响

基于经验的整体加工理论认为, 随着知觉经验的增多, 人们加工面孔的专家化能力逐渐增强。其中一种表现形式为, 在知觉面孔时更倾向于整体加工。该理论已经得到了一些实验证据的支持, 但未能解释另外一些研究的发现, 即对他族人群没有长期知觉经验的被试在加工他族面孔时也有强烈的整体加工。本研究旨在考察知觉经验对面孔整体加工的影响, 包括两个实验。实验1a通过组合面孔范式测量了中国被试在辨别本族面孔、他族面孔和种族融合面孔时的组合面孔效应(即面孔整体加工强度)。结果发现, 被试在知觉种族融合面孔时没有表现出组合面孔效应, 在知觉本族面孔和他族面孔时都表现出强烈的组合面孔效应。实验1b以灰阶图重复了实验1a。结果发现, 被试在知觉种族融合面孔时仍然没有表现出组合面孔效应, 在知觉本族面孔和他族面孔时表现出强烈的组合面孔效应。实验2通过操纵种族融合面孔的有或无, 测量5 s的知觉经验对融合面孔的组合效应的影响。结果发现, 在经过短时的知觉经验后, 被试在知觉融合面孔时也表现出强烈的组合面孔效应。上述实验结果表明, 中国被试在加工本族面孔、他族面孔和种族融合面孔时所诱发组合面孔效应有显著的、量的差别, 且这种整体加工的差异不会受到面孔肤色信息的影响。在经过短时的知觉经验后, 中国被试在加工种族融合面孔时表现出强烈的整体加工。该研究的发现提示, 不论是短时知觉经验还是长期知觉经验, 知觉经验的增加是面孔整体加工的一个关键要素。     

Face recognition as a predictor of social cognitive ability: Effects of emotion and race on face processing

The human face conveys important social signals when people interact in social contexts. The current study investigated the relationship between face recognition and emotional intelligence, and how societal factors of emotion and race influence people's face recognition. Participants’ recognition accuracy, reaction time, sensitivity, and response bias were measured to examine their face‐processing ability. Fifty Caucasian undergraduates (38 females, 12 males; average age = 21.76 years) participated in a face recognition task in which they discriminated previously presented target faces from novel distractor faces. A positive correlation between participants’ emotional intelligence scores and their performance on the face recognition task was observed, suggesting that face recognition ability was associated with emotional or social intelligence. Additionally, Caucasian participants recognized happy faces better than angry or neutral faces. It was also observed that people recognized Asian faces better than Caucasian ones, which appears to be contradictory to the classic other‐race effect. The present study suggests that some societal factors could influence face processing, and face recognition ability could in turn predict social intelligence.     

An encoding advantage for own-race versus other-race faces

Studies have shown that individuals are better able to recognise the faces of people from their own race than the faces of people from other races. Although the so-called own-race effect has been generally regarded as an advantage in recognition memory, differences in the processing of the own-race versus other-race faces might also be found at the earlier stages of perceptual encoding. In this study, the perceptual basis of the own-race effect was investigated by generating a continuum of images by morphing an East Asian parent face with a Caucasian parent face. In a same/different discrimination task, East Asian and Caucasian participants judged whether the morph faces were physically identical to, or different from, their parent faces. The results revealed a significant race-of-participant by race-of-face interaction such that East Asian participants were better able to discriminate East Asian faces, whereas Caucasian participants were better able to discriminate Caucasian faces. These results indicate that an own-race advantage occurs at the encoding stage of face processing.     

Does culture shape face perception in autism? Cross‐cultural evidence of the own‐race advantage from the UK and Japan

Autism spectrum disorders (ASD) are associated with face perception atypicalities, and atypical experience with faces has been proposed as an underlying explanation. Studying the own‐race advantage (ORA) for face recognition can reveal the effect of experience on face perception in ASD, although the small number of studies in the area present mixed findings. This study probed the ORA in ASD by comparing two cultural groups simultaneously for the first time. Children with ASD in the UK (N = 16) and Japan (N = 26) were compared with age‐ and ability‐matched typically developing (TD) children in the UK (N = 16) and Japan (N = 26). Participants completed a two‐alternative forced‐choice task, whereby they had to recognize a just seen face from a foil which was manipulated in one of four ways (IC: identity change; EE: easy eyes; HE: hard eyes; HM: hard mouth). Face stimuli were Asian and Caucasian, and thus the same stimuli were own and other race depending on the cultural group. The ASD groups in the UK and Japan did not show impaired face recognition abilities, or impairments with recognizing faces depending on manipulations to the eye region, and importantly they showed an ORA. There was considerable heterogeneity in the presence of the ORA in ASD and TD and also across cultures. Children in Japan had higher accuracy than children in the UK, and TD children in Japan did not show an ORA. This cross‐cultural study challenges the view that atypical experiences with faces lead to a reduced/absent ORA in ASD.     

Building biases in infancy: the influence of race on face and voice emotion matching

Early in the first year of life infants exhibit equivalent performance distinguishing among people within their own race and within other races. However, with development and experience, their face recognition skills become tuned to groups of people they interact with the most. This developmental tuning is hypothesized to be the origin of adult face processing biases including the other-race bias. In adults the other-race bias has also been associated with impairments in facial emotion processing for other-race faces. The present investigation aimed to show perceptual narrowing for other-race faces during infancy and to determine whether the race of a face influences infants' ability to match emotional sounds with emotional facial expressions. Behavioral (visual-paired comparison; VPC) and electrophysiological (event-related potentials; ERPs) measures were recorded in 5-month-old and 9-month-old infants. Behaviorally, 5-month-olds distinguished faces within their own race and within another race, whereas 9-month-olds only distinguish faces within their own race. ERPs were recorded while an emotion sound (laughing or crying) was presented prior to viewing an image of a static African American or Caucasian face expressing either a happy or a sad emotion. Consistent with behavioral findings, ERPs revealed race-specific perceptual processing of faces and emotion/sound face congruency at 9 months but not 5 months of age. In addition, from 5 to 9 months, the neural networks activated for sound/face congruency were found to shift from an anterior ERP component (Nc) related to attention to posterior ERP components (N290, P400) related to perception.     

A developmental investigation of other‐race contact and the own‐race face effect

Research over the past two decades has demonstrated that individuals are better at recognizing and discriminating faces of their own race versus other races. The own‐race effect has typically been investigated in relation to recognition memory; however, some evidence supports an own‐race effect at the level of perceptual encoding in adults. The current study investigated the developmental basis of the own‐race effect in White primary students (aged 7–11), secondary students (aged 12–15) and university students. Face stimuli were generated by morphing South Asian and White parent faces together along a linear continuum. In a same/different perceptual discrimination task, participants judged whether the face stimuli (morphs and parent faces) were physically identical to or different from the original parent faces. Results revealed a significant race of face effect for each age group, whereby participants were better at discriminating White relative to Asian faces. A significantly larger own‐race effect was observed for the secondary and university students than for primary students. A questionnaire was used to assess other‐race social anxiety and contact; however, this self‐report measure was not found to be related to the observed own‐race effect.