面孔识别异族效应的研究

异族效应是面孔识别过程中一种非常稳定的现象,表现为对本族面孔的识别与再认成绩显著高于异族面孔.脑成像研究也证实了这两类面孔在神经表征上的差异.关于该效应主要有知觉经验说与社会分类说两种理论解释,但围绕着其心理机制仍然存在着很多争议然,未来的研究需要考虑族群认同等社会-人格因素对于异族效应的影响,并注意考察本族面孔与异族面孔有提取阶段可能存在的神经活动的差异.     

Event-related brain potential correlates of the other-race effect: A review

People are better at remembering own-race relative to other-race faces. Here, we review event-related brain potential (ERP) correlates of this so-called other-‘race’ effect (ORE) by discussing three critical aspects that characterize the neural signature of this phenomenon. First, difficulties with other-race faces initially emerge during perceptual processing, which is indexed by an increased N170. Second, as evidenced by ‘difference due to subsequent memory’ effects, more effortful processing of other-race faces is needed for successful encoding into long-term memory. Third, ERP old/new effects reveal that a stronger engagement of processing resources is also required for successful retrieval of other-race faces from memory. The ERP evidence available to date thus suggests widespread ethnicity-related modulations during both perceptual and mnemonic processing stages. We further discuss how findings from the ORE compared with potentially related memory biases (e.g. other-gender or other-age effects) and how ERP findings inform the ongoing debate regarding the mechanisms underlying the ORE. Finally, we outline open questions and potential future directions with an emphasis on using multiple, ecologically more valid ‘ambient’ images for each face to assess the ORE in paradigms that capture identity rather than image recognition.     

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.     

面孔加工的结构编码阶段异族效应的加工方式： ERPs研究

实验采用事件相关电位（ERPs）技术,以大学生为被试,运用非洲、欧洲、亚洲三个不同种族的面孔照片,探究异族效应与加工方式的关系。行为实验结果显示,被试对非洲面孔的反应时快于欧洲面孔,且两者均快于亚洲面孔。ERP研究结果显示,亚洲面孔的N170波幅显著小于非洲和欧洲面孔的波幅,后两者的N170波幅没有差异,而且亚洲面孔的倒置效应最大。研究结果说明相对于异族面孔,本族面孔更多地使用构型编码的加工方式,且N170成分表现出右半球优势。     

Race categorization modulates holistic face encoding

Recent studies have shown that same-race (SR) faces are processed more holistically than other-race (OR) faces, a difference that may underlie the greater difficulty at recognizing OR than SR faces (the "other-race effect"). This article provides original evidence suggesting that the holistic processing of faces may be sensitive to the observers' racial categorization of the face. In Experiment 1, Caucasian participants performed a face-composite task with Caucasian faces, Asian faces, and racially ambiguous morphed face stimuli. Identical morphed face stimuli were processed more holistically when categorized as SR than as OR faces. Experiment 2 further suggests that this finding was not underlain by strategic or training effects. Overall, these results support the view that one's categorization of a face as belonging to the same or another race plays a critical role in the holistic processing of this face.     

Where the division lies: Common ingroup identity moderates the cross-race facial-recognition effect

This research investigated the hypothesis that better recognition for own-race than other-race faces is a result of social categorization rather than perceptual expertise. More specifically, we explored how the salience of race or university group boundaries would affect recall of faces. Using a modified facial recognition paradigm, on each trial eight Black and White faces were spatially organized either by race or university affiliation to induce categorization primarily based on one of these dimensions. When grouped by race, participants had superior recall for own-race faces and university affiliation had no effect. When grouped by university, participants had superior recall for own-university faces and race had no effect. Using identical stimuli across conditions, recall was superior for ingroup targets on the experimentally induced dimension of categorization, supportive of a social categorization based explanation of the cross-race effect.     

Face age and sex modulate the other-race effect in face recognition

Faces convey a variety of socially relevant cues that have been shown to affect recognition, such as age, sex, and race, but few studies have examined the interactive effect of these cues. White participants of two distinct age groups were presented with faces that differed in race, age, and sex in a face recognition paradigm. Replicating the other-race effect, young participants recognized young own-race faces better than young other-race faces. However, recognition performance did not differ across old faces of different races (Experiments 1, 2A). In addition, participants showed an other-age effect, recognizing White young faces better than White old faces. Sex affected recognition performance only when age was not varied (Experiment 2B). Overall, older participants showed a similar recognition pattern (Experiment 3) as young participants, displaying an other-race effect for young, but not old, faces. However, they recognized young and old White faces on a similar level. These findings indicate that face cues interact to affect recognition performance such that age and sex information reliably modulate the effect of race cues. These results extend accounts of face recognition that explain recognition biases (such as the other-race effect) as a function of dichotomous ingroup/outgroup categorization, in that outgroup characteristics are not simply additive but interactively determine recognition performance.     

Own- and other-race categorization of faces by race,gender, and age

We investigated how visual experience with faces of a particular race affects subordinate group-level categorizations in Chinese and Israeli participants living in the respective countries. Categorization of faces by race, gender, and age was examined within subjects with participants who had only minimal experience with the other-race faces. As would be predicted by the previously documented other-race advantage effect, both Chinese and Israeli participants classified the race of the face more quickly and more accurately for other-race than for own-race faces. In contrast, the observers’ race did not interact with the race of the rated face either for gender or for age categorization. The absence of these interactions suggests that the physiognomic characteristics that determine the gender and age of a face are universal, rather than race specific. Furthermore, these data suggest that determining the race of a face is not imposed as a first step in face processing, preempting the perception of other category-defining physiognomic characteristics.     

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.     

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。     

Perceptual expertise and the plasticity of other-race face recognition

In this paper, we argue that our ability to recognize own-race faces can be treated as a form of perceptual expertise. Similar to object experts (e.g., birdwatchers), people differentiate own-race faces at the subordinate level of categorization. In contrast, like novices, we tend to classify other-race faces at the basic level of race. We demonstrate that, as a form of perceptual expertise, other-race face recognition can be systematically taught in the lab through subordinate-level training. When participants learn to quickly and accurately differentiate other-race faces at the subordinate level of the individual, the individuating training transfers to improved recognition of untrained other-race faces, produces changes in event-related brain components, and reduces implicit racial bias. Subsequent work has shown that other-race learning can be optimized by directing participants to the diagnostic features of a racial group. The benefits of other-race training are fairly long-lived and are evident even 2 weeks after training. Collectively, the training studies demonstrate the plasticity of other-race face recognition. Rather than a process that is fixed by early developmental events, other-race face recognition is malleable and dynamic, continually being reshaped by the perceptual experiences of the observer.     

The influence of ingroup/outgroup categorization on same- and other-race face processing: The moderating role of inter- versus intra-racial context

We investigated the impact of ingroup/outgroup categorization on the encoding of same-race and other-race faces presented in inter-racial and intra-racial contexts (Experiments 1 and 2, respectively). White participants performed a same/different matching task on pairs of upright and inverted faces that were either same-race (White) or other-race (Black), and labeled as being from the same university or a different university. In Experiment 1, the same- and other-race faces were intermixed. For other-race faces, participants demonstrated greater configural processing following same- than other-university labeling. Same-race faces showed strong configural coding irrespective of the university labeling. In Experiment 2, faces were blocked by race. Participants demonstrated greater configural processing of same- than other-university faces, but now for both same- and other-race faces. These results demonstrate that other-race face processing is sensitive to non-racial ingroup/outgroup status regardless of racial context, but that the sensitivity of same-race face processing to the same cues depends on the racial context in which targets are encountered.     

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.     

Developing race categories in infancy via Bayesian face recognition

The other-race effect emerges during infancy following the perceptual narrowing of face recognition. Other-race faces that were previously discriminable in early infancy cannot be distinguished by older infants. I discuss a Bayesian model of this process that posits that the other-race effect may be a consequence of learning to distinguish between intrapersonal variation (changes to face appearance that preserve identity) and extrapersonal variation (changes that do not preserve identity) in a visual environment in which a subset of race categories dominate. I demonstrate that race categories, which I have previously argued are a critical precursor to the emergence of the other-race effect in infancy, are a natural by-product of this model. Perceptual narrowing for race may thus be a natural consequence of visual experience and the estimation of face variability based on a growing number of exemplars. I describe the basic architecture of the model, its applicability to a range of visual learning scenarios, and identify critical choices one faces in applying the model to a specific perceptual task. Despite the success of the model in accounting for these behavioural results, I conclude by identifying important shortcomings of the model and describe important challenges for future efforts to characterize the development of the other-race effect computationally.     

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.     

Shape, color and the other-race effect in the infant brain

The 'other-race' effect describes the phenomenon in which faces are difficult to distinguish from one another if they belong to an ethnic or racial group to which the observer has had little exposure. Adult observers typically display multiple forms of recognition error for other-race faces, and infants exhibit behavioral evidence of a developing other-race effect at about 9 months of age. The neural correlates of the adult other-race effect have been identified using ERPs and fMRI, but the effects of racial category on infants' neural response to face stimuli have to date not been described. We examine two distinct components of the infant ERP response to human faces and demonstrate through the use of computer-generated 'hybrid' faces that the observed other-race effect is not the result of low-level sensitivity to 3D shape and color differences between the stimuli. Rather, differential processing depends critically on the joint encoding of race-specific features.     

Processes underlying the cross-race effect: an investigation of holistic, featural, and relational processing of own-race versus other-race faces

Adults are often better at recognising own-race than other-race faces. Unlike previous studies that reported an own-race advantage after administering a single test of either holistic processing or of featural and relational processing, we used a cross-over design and multiple tasks to assess differential processing of faces from a familiar race versus a less familiar race. Caucasian and Chinese adults performed four tasks, each with Caucasian and Chinese faces. Two tasks measured holistic processing: the composite face task and the part/whole task. Both tasks indicated holistic processing of own-race and other-race faces that did not differ in degree. Two tasks measured featural and relational processing: the Jane/Ling task, in which same/ different judgments were made about face pairs that differed in features of their spacing, and the scrambled/blurred task, in which test faces were scrambled (isolates memory for components) or blurred (isolates memory for relations). Both tasks provided evidence of an own-race advantage in both featural and relational processing. We conclude that even when adults process other-race faces holistically, other manifestations of an own-race advantage remain.     

Can massive but passive exposure to faces contribute to face recognition abilities?

Recent studies have suggested that individuation of other-race faces is more crucial for enhancing recognition performance than exposure that involves categorization of these faces to an identity-irrelevant criterion. These findings were primarily based on laboratory training protocols that dissociated exposure and individuation by using categorization tasks. However, the absence of enhanced recognition following categorization may not simulate key aspects of real-life massive exposure without individuation to other-race faces. Real-life exposure spans years of seeing a multitude of faces, under variant conditions, including expression, view, lighting and gaze, albeit with no subcategory individuation. However, in most real-life settings, massive exposure operates in concert with individuation. An exception to that are neonatology nurses, a unique population that is exposed to--but do not individuate--massive numbers of newborn faces. Our findings show that recognition of newborn faces by nurses does not differ from adults who are rarely exposed to newborn faces. A control study showed that the absence of enhanced recognition cannot be attributed to the relatively short exposure to each newborn face in the neonatology unit or to newborns' apparent homogeneous appearance. It is therefore the quality--not the quantity--of exposure that determines recognition abilities.     

孤独症谱系障碍患者对种族情境中本异族面孔的眼动模式

本研究采用眼动技术探讨孤独症谱系障碍(ASD)患者对背景中的本异族面孔的加工特点。研究采用2（组别）×2（面孔种族）×3（背景）的混合设计,让16名16-25岁的ASD患者和17名生理年龄匹配的正常人完成变化检测任务,并记录他们的眼动。结果显示：与正常人相比,ASD患者的面孔辨别力更低;他们的眼动呈现更多的面孔-背景眼跳和更多的上下半脸眼跳;两组被试的上下半脸眼跳的次数受到面孔种族以及面孔和背景是否一致的影响。结论：在行为指标上,正常人出现了本族效应,而ASD患者没有出现本族效应;在眼动上,ASD患者呈现与正常人相似的面孔注视时间,但比正常人呈现更多的眼跳。面孔的背景影响了面孔辨别力以及上下半脸眼跳轨迹。     

Identification of own-race and other-race faces: Implications for the representation of race in face space

Own-race faces are recognized more easily than faces of a different, unfamiliar race. According to the multidimensional space (MDS) framework, the poor discriminability of other-race faces is due to their being more densely clustered in face space than own-race faces. Multidimensional scaling analyses of similarity ratings (Caucasian participants, n = 22) showed that other-race (Chinese) faces are more densely clustered in face space. We applied a formal model to test whether the spatial location of face stimuli could account for identification accuracy of another group of Caucasian participants (n = 30). As expected, own-race (Caucasian) faces were identified more accurately (higher hit rate, lower false alarms, and higher A) than other-race faces, which were more densely clustered than ownrace faces. A quantitative model successfully predicted identification performance from the spatial locations of the stimuli. The results are discussed in relation to the standard MDS account of race effects and also an alternative “race-feature” hypothesis.