Perceptual narrowing continues throughout childhood: Evidence from specialization of face processing.

Face recognition shows a long trajectory of development and is known to be closely associated with the development of social skills. However, it is still debated whether this long trajectory is perceptually based and what the role is of experience-based refinements of face representations throughout development. We examined the effects of short and long-term experienced stimulus history on face processing, using regression biases of face representations towards the experienced mean. Children and adults performed same-different judgments in a serial discrimination task where two consecutive faces were drawn from a distribution of morphed faces. The results show that face recognition continues to improve after 9 years of age, with more pronounced improvements for own-race faces. This increased narrowing with age is also indicated by similar use of stimulus statistics for own-race and other-race faces in children, contrary to the different use of the overall stimulus history for these two face types in adults. Increased face proficiency in adulthood renders the perceptual system less tuned to other-race face statistics. Altogether, the results demonstrate associations between levels of specialization and the extent to which perceptual representations become narrowly tuned with age.

Do They Look the Same Unless They Are Angry? Investigating the Other-Race Effect in the Presence of Angry Expressions.

Ethnic out-group members are disproportionately more often the victim of misidentifications. The so-called other-race effect (ORE), the tendency to better remember faces of individuals belonging to one's own ethnic in-group than faces belonging to an ethnic out-group, has been identified as one causal ingredient in such tragic incidents. Investigating an important aspect for the ORE-that is, emotional expression-the seminal study by Ackerman and colleagues (2006) found that White participants remembered neutral White faces better than neutral Black faces, but crucially, Black angry faces were better remembered than White angry faces (i.e., a reversed ORE). In the current study, we sought to replicate this study and directly tackle the potential causes for different results with later work. Three hundred ninety-six adult White U.S. citizens completed our study in which we manipulated the kind of employed stimuli (as in the original study vs. more standardized ones) whether participants knew of the recognition task already at the encoding phase. Additionally, participants were asked about the unusualness of the presented faces. We were able to replicate results from the Ackerman et al. (2006) study with the original stimuli but not with more standardized stimuli.

Infants' top-down perceptual modulation is specific to own-race faces.

Recent studies have revealed the influence of higher-level cognitive systems in modulating perceptual processing (top-down perceptual modulation) in infancy. However, more research is needed to understand how top-down processes in infant perception contribute to early perceptual development. To this end, this study examined infants' top-down perception of own- and other-race faces to reveal whether top-down modulation is linked to the emergence of perceptual specialization. Infants first learned an association between a sound and faces, with the race of the faces manipulated between groups (own race vs. other race). We then tested infants' face perception across various levels of perceptual difficulty (manipulated by presentation duration) and indexed top-down perception by the change in perception when infants heard the sound previously associated with the face (predictive sound) versus an irrelevant sound. Infants exhibited top-down face perception for own-race faces (Experiment 1). However, we present new evidence that infants did not show evidence of top-down modulation for other-race faces (Experiment 2), suggesting an experience-based specificity of this capacity with more effective top-down modulation in familiar perceptual contexts. In addition, we ruled out the possibility that this face race effect was due to differences in infants' associative learning of the sound and faces between the two groups. This work has important implications for understanding the mechanisms supporting perceptual development and how they relate to top-down perception in infancy.

Event-related potential correlates of implicit processing of own- and other-race faces in children.

Human adults typically experience difficulties in recognizing and discriminating individual faces belonging to racial groups other than their own. The origin of this "other-race" effect is set in infancy, but the understanding of its developmental course is fragmented. We aimed to access the mechanisms of the other-race effect in childhood by unraveling the neural time course of own- and other-race face processing during a masked priming paradigm. White 6- and 7-year-old children (N = 19) categorized fully visible Asian (other-race) or White (own-race) target faces according to gender. Target faces were preceded by masked same-identity or different-identity prime faces, matching the target for race and gender. We showed an early priming effect on the N100 component, with larger amplitude to different-face pairs than to same-face pairs, and a later race effect on the N200 component, with larger amplitude to own-race face pairs than to other-race face pairs. Critically, race did not interact with priming at any processing stage (P100, N100, P200, N200, or P300). Our results suggest that race could have a temporally limited impact on face processing and that the implicit and unconscious identity processing of own- and other-race faces could be similar in 6- and 7-year-olds, depicting an immature other-race effect during childhood.

The cross-race effect in automatic facial expression recognition violates measurement invariance.

Emotion has been a subject undergoing intensive research in psychology and cognitive neuroscience over several decades. Recently, more and more studies of emotion have adopted automatic rather than manual methods of facial emotion recognition to analyze images or videos of human faces. Compared to manual methods, these computer-vision-based, automatic methods can help objectively and rapidly analyze a large amount of data. These automatic methods have also been validated and believed to be accurate in their judgments. However, these automatic methods often rely on statistical learning models (e.g., deep neural networks), which are intrinsically inductive and thus suffer from problems of induction. Specifically, the models that were trained primarily on Western faces may not generalize well to accurately judge Eastern faces, which can then jeopardize the measurement invariance of emotions in cross-cultural studies. To demonstrate such a possibility, the present study carries out a cross-racial validation of two popular facial emotion recognition systems-FaceReader and DeepFace-using two Western and two Eastern face datasets. Although both systems could achieve overall high accuracies in the judgments of emotion category on the Western datasets, they performed relatively poorly on the Eastern datasets, especially in recognition of negative emotions. While these results caution the use of these automatic methods of emotion recognition on non-Western faces, the results also suggest that the measurements of happiness outputted by these automatic methods are accurate and invariant across races and hence can still be utilized for cross-cultural studies of positive psychology.

Community diversity and the other-race effect in infancy.

The other-race effect (ORE) is characterized by processing advantages for faces of one's own race over faces of another race and is observed at ~9 months of age. Environmental exposure to other races has an impact on the development of the ORE. In the current study, we examined the effects of community racial diversity on the ORE in 9- to 12-month-olds from across the United States. We hypothesized that community racial diversity would influence the amount of experience that infants have with individuals of other races and be an important factor in predicting the ORE across broad regions of the United States. We predicted that infants from more diverse communities would demonstrate successful processing of own- and other-race faces, while infants from less diverse communities would demonstrate successful processing of own-race but not other-race faces. This would indicate that the ORE is exhibited more strongly in infants from less diverse communities than in infants from more diverse communities. Participants completed familiarization and visual paired comparison (VPC) trials with own- and other-race faces in an online study. Our results showed that although the ORE was present, the effect was driven by community members who were the racial majority. Recognition biases were not observed in community racial or ethnic minority participants, potentially due to increased exposure to racial out-group members, which mitigated the development of the ORE in this subset of participants. This study has far-reaching implications in the study of infant face perception, child development, and social justice, as the ORE develops at a young age, and may lead to a complex pattern of racial biases contributing to systemic barriers in society.

Age Weakens the Other-Race Effect among Han Subjects in Recognizing Own- and Other-Ethnicity Faces.

The development and change in the other-race effect (ORE) in different age groups have always been a focus of researchers. Previous studies have mainly focused on the influence of maturity of life (from infancy to early adulthood) on the ORE, while few researchers have explored the ORE in older people. Therefore, this study used behavioral and eye movement techniques to explore the influence of age on the ORE and the visual scanning pattern of Han subjects recognizing own- and other-ethnicity faces. All participants were asked to complete a study-recognition task for faces, and the behavioral results showed that the ORE of elderly Han subjects was significantly lower than that of young Han subjects. The results of eye movement showed that there were significant differences in the visual scanning pattern of young subjects in recognizing the faces of individuals of their own ethnicity and other ethnicities, which were mainly reflected in the differences in looking at the nose and mouth, while the differences were reduced in the elderly subjects. The elderly subjects used similar scanning patterns to recognize the own- and other-ethnicity faces. This indicates that as age increases, the ORE of older people in recognizing faces of those from different ethnic groups becomes weaker, and elderly subjects have more similar visual scanning patterns in recognizing faces of their own and other ethnicities.

Collaboration to improve cross-race face identification: Wisdom of the multi-racial crowd?

Face identification is particularly prone to error when individuals identify people of a race other than their own - a phenomenon known as the other-race effect (ORE). Here, we show that collaborative "wisdom-of-crowds" decision-making substantially improves face identification accuracy for own- and other-race faces over individuals working alone. In two online experiments, East Asian and White individuals recognized own- and other-race faces as individuals and as part of a collaborative dyad. Collaboration never proved more beneficial in a social setting than when individual identification decisions were combined computationally. The reliable benefit of non-social collaboration may stem from its ability to avoid the potential negative outcomes of group diversity such as conflict. Consistent with this benefit, the racial diversity of collaborators did not influence either general or race-specific face identification accuracy. Our findings suggest that collaboration between two individuals is a promising strategy for improving cross-race face identification that may translate effectively into forensic and eyewitness settings.

Default categorization of outgroup faces and the other race effect: Commentary on the special issue.

This commentary addresses how studies examining the neurophysiological correlates of racial categorization can provide insight into the neurocognitive mechanisms of the other-race effect in recognition memory. Several articles in the special issue describe how event-related potentials (ERPs) have been used to examine processing of faces that vary according to race, some of which have concluded that larger ERP amplitudes elicited by other-race (relative to own-race) faces indicates less efficient visual processing of other-race faces. I describe findings from ERP studies of race categorization that suggest an alternative interpretation-that other-race faces elicit stronger categorization, which impedes individuation of other-race faces. Suggestions for future research are offered.

The culture of perceptual expertise and the other-race effect.

In our commentary, we propose that the ORE can be viewed as a form of perceptual expertise. Like experts, we recognize own-race faces at the subordinate level as individuals and novices when recognize other-race faces at the basic level of race. Applying a perceptual expertise account, we explain the ORE in terms of its cognitive, neural, and motivational factors. We suggest that by creating a culture of "other-race" expertise, improvements in other-race face recognition can be achieved.

Visual attention to own- versus other-race faces: Perspectives from learning mechanisms and task demands.

Multiple factors have been proposed to contribute to the other-race effect in face recognition, including perceptual expertise and social-cognitive accounts. Here, we propose to understand the effect and its contributing factors from the perspectives of learning mechanisms that involve joint learning of visual attention strategies and internal representations for faces, which can be modulated by quality of contact with other-race individuals including emotional and motivational factors. Computational simulations of this process will enhance our understanding of interactions among factors and help resolve inconsistent results in the literature. In particular, since learning is driven by task demands, visual attention effects observed in different face-processing tasks, such as passive viewing or recognition, are likely to be task specific (although may be associated) and should be examined and compared separately. When examining visual attention strategies, the use of more data-driven and comprehensive eye movement measures, taking both spatial-temporal pattern and consistency of eye movements into account, can lead to novel discoveries in other-race face processing. The proposed framework and analysis methods may be applied to other tasks of real-life significance such as face emotion recognition, further enhancing our understanding of the relationship between learning and visual cognition.

Face race and sex impact visual fixation strategies for upright and inverted faces in 3- to 6-year-old children.

Everyday face experience tends to be biased, such that infants and young children interact more often with own-race and female faces leading to differential processing of faces within these groups relative to others. In the present study, visual fixation strategies were recorded using eye tracking to determine the extent to which face race and sex/gender impact a key index of face processing in 3- to 6-year-old children (n = 47). Children viewed male and female upright and inverted White and Asian faces while visual fixations were recorded. Face orientation was found to have robust effects on children's visual fixations, such that children exhibited shorter first fixation and average fixation durations and a greater number of fixations for inverted compared to upright face trials. First fixations to the eye region were also greater for upright compared to inverted faces. Fewer fixations and longer duration fixations were found for trials with male compared to female faces and for upright compared to inverted unfamiliar-race faces, but not familiar-race faces. These findings demonstrate evidence of differential fixation strategies toward different types of faces in 3- to 6-year-old children, illustrating the importance of experience in the development of visual attention to faces.

Is the Other-Race Effect in Working Memory Due to Attentional Refreshing?

The other-race effect is the observation that faces from another ethnicity induce worst recall performance than faces from one's own ethnicity. This effect has been defined as a type of familiarity effect, with more familiar faces better recalled than less familiar faces. In this study, we tested the hypothesis that a working memory maintenance mechanism called attentional refreshing mediates the other-race effect and that faces from one's own ethnicity are refreshed more efficiently than faces from other ethnicities. In two experiments, face ethnicity was orthogonally manipulated with cognitive load of a concurrent processing task in a complex-span paradigm (Exp. 1) and with the memory load in a Brown-Peterson paradigm (Exp. 2). Both cognitive and memory load effects are indices of the functioning of attentional refreshing. Testing Caucasian young adults, Caucasian and East-Asian faces were contrasted. Results from both experiments were congruent and against our initial hypothesis. The other-race effect in working memory does not appear to be supported by attentional refreshing. Furthermore, the results are congruent with the idea that faces as a whole are not maintained in working memory via attentional refreshing.

On the role of experience versus motivation in predicting the own-race effect.

The other-race effect (ORE) is a longstanding phenomenon in experimental psychology, where recognition for same-race faces is superior than for other-race faces. The present research pits two competing theories of perceptual expertise and social motivation against each other to see which is the more robust predictor of the ORE. In Study 1, we measured Black and White participants' prior contact with individuals from the other-race (i.e. expertise) as well as their expected level of future interaction with other-race individuals (i.e. motivation). Of the two theories, anticipated interaction (i.e. motivation) emerged as a significant predictor of the ORE. Study 2 followed the same design, measuring motivation with a self-report assessment of how much participants are willing to have cross-race friendships. Here, neither experience nor motivation predicted the ORE, though an ORE was established. Differences in measures that assess motivation and the experience versus motivation debate are discussed.

Do they 'look' different(ly)? Dynamic face recognition in Malaysians: Chinese, Malays and Indians compared.

Previous cross-cultural eye-tracking studies examining face recognition discovered differences in the eye movement strategies that observers employ when perceiving faces. However, it is unclear (1) the degree to which this effect is fundamentally related to culture and (2) to what extent facial physiognomy can account for the differences in looking strategies when scanning own- and other-race faces. In the current study, Malay, Chinese and Indian young adults who live in the same multiracial country performed a modified yes/no recognition task. Participants' recognition accuracy and eye movements were recorded while viewing muted face videos of own- and other-race individuals. Behavioural results revealed a clear own-race advantage in recognition memory, and eye-tracking results showed that the three ethnic race groups adopted dissimilar fixation patterns when perceiving faces. Chinese participants preferentially attended more to the eyes than Indian participants did, while Indian participants made more and longer fixations on the nose than Malay participants did. In addition, we detected statistically significant, though subtle, differences in fixation patterns between the faces of the three races. These findings suggest that the racial differences in face-scanning patterns may be attributed both to culture and to variations in facial physiognomy between races.

6- to 10-year-old children do not show race-based orienting biases to faces during an online attention capture task.

Research has established that frequency of exposure to own- and other-race faces shapes the development of face processing biases characterized by enhanced attention to and recognition of more familiar own-race faces, that is, the other-race effect (ORE). The ORE is first evident during infancy based on differences in looking to own- versus other-race faces and is later assessed based on recognition memory task performance during childhood and adulthood. Using these measures, researchers have found that race-based face processing biases initially develop during infancy but remain sensitive to experiences with own- and other-race faces through childhood. In contrast, limited work suggests that infants' attention orienting may be less affected by frequency of exposure to own- and other-race faces. However, the plasticity of race-based face processing biases during childhood suggests that biased orienting to own-race faces may develop at later ages following continued exposure to these faces. We addressed this question by examining 6- to 10-year-old children's attention capture by own- and other-race faces during an online task. Children searched for a target among multiple distractors. During some trials, either an own- or other-race face appeared as one of the distractors. Children showed similar target detection performance (omission errors, accuracy, and response times) regardless of whether an own- or other-race face appeared as a distractor. These results differ from research demonstrating race-based biases in attention holding and recognition memory but converge with previous infant research suggesting that attention orienting might not be as strongly affected by frequency of exposure to race-based information during development.

Why the other-race effect matters: Poor recognition of other-race faces impacts everyday social interactions.

What happens to everyday social interactions when other-race recognition fails? Here, we provide the first formal investigation of this question. We gave East Asian international students (N = 89) a questionnaire concerning their experiences of the other-race effect (ORE) in Australia, and a laboratory test of their objective other-race face recognition deficit using the Cambridge Face Memory Test (CFMT). As a 'perpetrator' of the ORE, participants reported that their problems telling apart Caucasian people contributed significantly to difficulties socializing with them. Moreover, the severity of this problem correlated with their ORE on the CFMT. As a 'victim' of the ORE, participants reported that Caucasians' problems telling them apart also contributed to difficulties socializing. Further, 81% of participants had been confused with other Asians by a Caucasian authority figure (e.g., university tutor, workplace boss), resulting in varying levels of upset/difficulty. When compared to previously established contributors to international students' high rates of social isolation, ORE-related problems were perceived as equally important as the language barrier and only moderately less important than cultural differences. We conclude that the real-world impact of the ORE extends beyond previously identified specialized settings (eyewitness testimony, security), to common everyday situations experienced by all humans.

Asymmetrical responding to male versus female other-race categories in 9- to 12-month-old infants.

Faces can be categorized along various dimensions including gender or race, an ability developing in infancy. Infant categorization studies have focused on facial attributes in isolation, but the interaction between these attributes remains poorly understood. Experiment 1 examined gender categorization of other-race faces in 9- and 12-month-old White infants. Nine- and 12-month-olds were familiarized with Asian male or female faces, and tested with a novel exemplar from the familiarized category paired with a novel exemplar from a novel category. Both age groups showed novel category preferences for novel Asian female faces after familiarization with Asian male faces, but showed no novel category preference for novel Asian male faces after familiarization with Asian female faces. This categorization asymmetry was not due to a spontaneous preference hindering novel category reaction (Experiment 2), and both age groups displayed difficulty discriminating among male, but not female, other-race faces (Experiment 3). These results indicate that category formation for male other-race faces is mediated by categorical perception. Overall, the findings suggest that even by 12 months of age, infants are not fully able to form gender category representations of other-race faces, responding categorically to male, but not female, other-race faces.

Understanding the mechanisms underlying the other-'race' effect: An attempt at integrating different perspectives.

Although different human races do not exist from the perspective of biology and genetics, ascribed 'race' influences psychological processing, such as memory and perception of faces. Research from this Special Issue, as well as a wealth of previous research, shows that other-'race' faces are more difficult to recognize compared to own-'race' faces, a phenomenon known as the other-'race' effect. Theories of expertise attribute the cause of the other-'race' effect to less efficient visual representations of other-'race' faces, which results from reduced visual expertise with other-'race' faces compared to own-'race' faces due to limited contact with individuals from other 'racial' groups. By contrast, social-cognitive accounts attribute the cause of the other-'race' effect to reduced motivation to individuate other-'race' faces compared to own-'race' faces. Evidence for both types of theories is still mixed, but progress in understanding the phenomenon has also been hampered by the fact that there has been little crosstalk between these accounts, which tend to be rooted in separate domains of experimental perception science and social psychology, respectively. To promote an integrative perspective on current knowledge on own- versus other-'race' face processing, the present Special Issue bridges different psychological subdisciplines, showcasing research using a large variety of methodological approaches and measures. In this guest editorial, we briefly highlight individual contributions to this Special Issue and offer what we see as important avenues for future research on the other-'race' effect.

The other-race effect in facial expression processing: Behavioral and ERP evidence from a balanced cross-cultural study in women.

Although evidence for cultural variants in facial expression decoding is accumulating, the other-race effect in facial expression processing and its neural correlates are still unclear. We investigated this question with a fully balanced design, in which a group of East Asian and a group of European Caucasian women categorized pictures of sad, happy, angry, and neutral facial expressions posed by individuals of their own-race and the other-race. Results revealed a disadvantage in categorizing expressions of anger in other-race faces in both samples, and for sad expressions in the European sample only. Partially consistent, East Asian participants showed longer latency of the N170 component in the event-related potential (ERP) and European Caucasian participants showed larger N170 amplitudes to other-race faces. The late positive complex in the ERP was less distinguishable among other-race facial expressions. Therefore, the present study observed an other-race effect in early and late stages of face processing, reflecting less efficient structural encoding and less elaborate processing for other-race than own-race faces.