Dynamic representations of race: processing goals shape race decoding in the fusiform gyri

Uncertain threat is associated with greater impulsive actions and neural dissimilarity to Black versus White faces

Race is a social construct that contributes to group membership and heightens emotional arousal in intergroup contexts. Little is known about how emotional arousal, specifically uncertain threat, influences behavior and brain processes in response to race information. We investigated the effects of experimentally manipulated uncertain threat on impulsive actions to Black versus White faces in a community sample (n = 106) of Black and White adults. While undergoing fMRI, participants performed an emotional go/no-go task under three conditions of uncertainty: 1) anticipation of an uncertain threat (i.e., unpredictable loud aversive sound); 2) anticipation of an uncertain reward (i.e., unpredictable receipt of money); and 3) no anticipation of an uncertain event. Representational similarity analysis was used to examine the neural representations of race information across functional brain networks between conditions of uncertainty. Participants-regardless of their own race-showed greater impulsivity and neural dissimilarity in response to Black versus White faces across all functional brain networks in conditions of uncertain threat relative to other conditions. This pattern of greater neural dissimilarity under threat was enhanced in individuals with high implicit racial bias. Our results illustrate the distinct and important influence of uncertain threat on global differentiation in how race information is represented in the brain, which may contribute to racially biased behavior.

Exposure to Multicultural Context Affects Neural Response to Out-Group Faces: A Functional Magnetic Resonance Imaging Study

Recent migration and globalization trends have led to the emergence of ethnically, religiously, and linguistically diverse countries. Understanding the unfolding of social dynamics in multicultural contexts becomes a matter of common interest to promote national harmony and social cohesion among groups. The current functional magnetic resonance imaging (fMRI) study aimed to (i) explore the neural signature of the in-group bias in the multicultural context; and (ii) assess the relationship between the brain activity and people's system-justifying ideologies. A sample of 43 (22 females) Chinese Singaporeans (M = 23.36; SD = 1.41) was recruited. All participants completed the Right Wing Authoritarianism Scale and Social Dominance Orientation Scale to assess their system-justifying ideologies. Subsequently, four types of visual stimuli were presented in an fMRI task: Chinese (in-group), Indian (typical out-group), Arabic (non-typical out-group), and Caucasian (non-typical out-group) faces. The right middle occipital gyrus and the right postcentral gyrus showed enhanced activity when participants were exposed to in-group (Chinese) rather than out-group (Arabic, Indian, and Caucasian) faces. Regions having a role in mentalization, empathetic resonance, and social cognition showed enhanced activity to Chinese (in-group) rather than Indian (typical out-group) faces. Similarly, regions typically involved in socioemotional and reward-related processing showed increased activation when participants were shown Chinese (in-group) rather than Arabic (non-typical out-group) faces. The neural activations in the right postcentral gyrus for in-group rather than out-group faces and in the right caudate in response to Chinese rather than Arabic faces were in a significant positive correlation with participants' Right Wing Authoritarianism scores (p < 0.05). Furthermore, the activity in the right middle occipital gyrus for Chinese rather than out-group faces was in a significant negative correlation with participants' Social Dominance Orientation scores (p < 0.05). Results are discussed by considering the typical role played by the activated brain regions in socioemotional processes as well as the role of familiarity to out-group faces.

Prosopagnosia does not abolish other-race effects

Healthy observers recognize more accurately same-than other-race faces (i.e., the Same-Race Recognition Advantage - SRRA) but categorize them by race more slowly than other-race faces (i.e., the Other-Race Categorization Advantage - ORCA). Several fMRI studies reported discrepant bilateral activations in the Fusiform Face Area (FFA) and Occipital Face Area (OFA) correlating with both effects. However, due to the very nature and limits of fMRI results, whether these face-sensitive regions play an unequivocal causal role in those other-race effects remains to be clarified. To this aim, we tested PS, a well-studied pure case of acquired prosopagnosia with lesions encompassing the left FFA and the right OFA. PS, healthy age-matched and young adults performed two recognition and three categorization by race tasks, respectively using Western Caucasian and East Asian faces normalized for their low-level properties with and without-external features, as well as in naturalistic settings. As expected, PS was slower and less accurate than the controls. Crucially, however, the magnitudes of her SRRA and ORCA were comparable to the controls in all the tasks. Our data show that prosopagnosia does not abolish other-race effects, as an intact face system, the left FFA and/or right OFA are not critical for eliciting the SRRA and ORCA. Race is a strong visual and social signal that is encoded in a large neural face-sensitive network, robustly tuned for processing same-race faces.

Processing of Task-Irrelevant Race Information is Associated with Diminished Cognitive Control in Black and White Individuals

The race of an individual is a salient physical feature that is rapidly processed by the brain and can bias our perceptions of others. How the race of others explicitly impacts our actions toward them during intergroup contexts is not well understood. In the current study, we examined how task-irrelevant race information influences cognitive control in a go/no-go task in a community sample of Black (n = 54) and White (n = 51) participants. We examined the neural correlates of behavioral effects using functional magnetic resonance imaging and explored the influence of implicit racial attitudes on brain-behavior associations. Both Black and White participants showed more cognitive control failures, as indexed by dprime, to Black versus White faces, despite the irrelevance of race to the task demands. This behavioral pattern was paralleled by greater activity to Black faces in the fusiform face area, implicated in processing face and in-group information, and lateral orbitofrontal cortex, associated with resolving stimulus-response conflict. Exploratory brain-behavior associations suggest different patterns in Black and White individuals. Black participants exhibited a negative association between fusiform activity and response time during impulsive errors to Black faces, whereas White participants showed a positive association between lateral OFC activity and cognitive control performance to Black faces when accounting for implicit racial associations. Together our findings propose that attention to race information is associated with diminished cognitive control that may be driven by different mechanisms for Black and White individuals.

Stereotypes bias face perception via orbitofrontal-fusiform cortical interaction

Previous research has shown that social-conceptual associations, such as stereotypes, can influence the visual representation of faces and neural pattern responses in ventral temporal cortex (VTC) regions, such as the fusiform gyrus (FG). Current models suggest that this social-conceptual impact requires medial orbitofrontal cortex (mOFC) feedback signals during perception. Backward masking can disrupt such signals, as it is a technique known to reduce functional connectivity between VTC regions and regions outside VTC. During functional magnetic resonance imaging (fMRI), subjects passively viewed masked and unmasked faces, and following the scan, perceptual biases and stereotypical associations were assessed. Multi-voxel representations of faces across the VTC, and in the FG and mOFC, reflected stereotypically biased perceptions when faces were unmasked, but this effect was abolished when faces were masked. However, the VTC still retained the ability to process masked faces and was sensitive to their categorical distinctions. Functional connectivity analyses confirmed that masking disrupted mOFC-FG connectivity, which predicted a reduced impact of stereotypical associations in the FG. Taken together, our findings suggest that the biasing of face representations in line with stereotypical associations does not arise from intrinsic processing within the VTC and FG alone, but instead it depends in part on top-down feedback from the mOFC during perception.

Dynamic interactive theory as a domain-general account of social perception

The perception of social categories, emotions, and personality traits from others' faces each have been studied extensively but in relative isolation. We synthesize emerging findings suggesting that, in each of these domains of social perception, both a variety of bottom-up facial features and top-down social cognitive processes play a part in driving initial perceptions. Among such top-down processes, social-conceptual knowledge in particular can have a fundamental structuring role in how we perceive others' faces. Extending the Dynamic Interactive framework (Freeman & Ambady, 2011), we outline a perspective whereby the perception of social categories, emotions, and traits from faces can all be conceived as emerging from an integrated system relying on domain-general cognitive properties. Such an account of social perception would envision perceptions to be a rapid, but gradual, process of negotiation between the variety of visual cues inherent to a person and the social cognitive knowledge an individual perceiver brings to the perceptual process. We describe growing evidence in support of this perspective as well as its theoretical implications for social psychology.

Neural representation of current and intended task sets during sequential judgements on human faces

Engaging in a demanding activity while holding in mind another task to be performed in the near future requires the maintenance of information about both the currently-active task set and the intended one. However, little is known about how the human brain implements such action plans. While some previous studies have examined the neural representation of current task sets and others have investigated delayed intentions, to date none has examined the representation of current and intended task sets within a single experimental paradigm. In this fMRI study, we examined the neural representation of current and intended task sets, employing sequential classification tasks on human faces. Multivariate decoding analyses showed that current task sets were represented in the orbitofrontal cortex (OFC) and fusiform gyrus (FG), while intended tasks could be decoded from lateral prefrontal cortex (lPFC). Importantly, a ventromedial region in PFC/OFC contained information about both current and delayed tasks, although cross-classification between the two types of information was not possible. These results help delineate the neural representations of current and intended task sets, and highlight the importance of ventromedial PFC/OFC for maintaining task-relevant information regardless of when it is needed.

Neural adaptation to faces reveals racial outgroup homogeneity effects in early perception

The tendency to view members of social outgroups as interchangeable has long been considered a core component of intergroup bias and a precursor to stereotyping and discrimination. However, the early perceptual nature of these intergroup biases is poorly understood. Here, we used a functional MRI adaptation paradigm to assess how face-selective brain regions respond to variation in physical similarity among racial ingroup (White) and outgroup (Black) faces. We conclude that differences emerge in the different tuning properties of early face-selective cortex for racial ingroup and outgroup faces and mirror behavioral differences in memory and perception of racial ingroup versus outgroup faces. These results suggest that outgroup deindividuation emerges at some of the earliest stages of perception.

A hallmark of intergroup biases is the tendency to individuate members of one’s own group but process members of other groups categorically. While the consequences of these biases for stereotyping and discrimination are well-documented, their early perceptual underpinnings remain less understood. Here, we investigated the neural mechanisms of this effect by testing whether high-level visual cortex is differentially tuned in its sensitivity to variation in own-race versus other-race faces. Using a functional MRI adaptation paradigm, we measured White participants’ habituation to blocks of White and Black faces that parametrically varied in their groupwise similarity. Participants showed a greater tendency to individuate own-race faces in perception, showing both greater release from adaptation to unique identities and increased sensitivity in the adaptation response to physical difference among faces. These group differences emerge in the tuning of early face-selective cortex and mirror behavioral differences in the memory and perception of own- versus other-race faces. Our results suggest that biases for other-race faces emerge at some of the earliest stages of sensory perception.

Decoding the neural representation of self and person knowledge with multivariate pattern analysis and data-driven approaches

Multivariate pattern analysis and data-driven approaches to understand how the human brain encodes sensory information and higher level conceptual knowledge have become increasingly dominant in visual and cognitive neuroscience; however, it is only in recent years that these methods have been applied to the domain of social information processing. This review examines recent research in the field of social cognitive neuroscience focusing on how multivariate pattern analysis (e.g., pattern classification, representational similarity analysis) and data-driven methods (e.g., reverse correlation, intersubject correlation) have been used to decode and characterize high-level information about the self, other persons, and social groups. We begin with a review of what is known about how self-referential processing and person perception are represented in the medial prefrontal cortex based on conventional activation-based neuroimaging approaches. This is followed by a nontechnical overview of current multivariate pattern-based and data-driven neuroimaging methods designed to characterize and/or decode neural representations. The remainder of the review focuses on examining how these methods have been applied to the topic of self, person perception, and the perception of social groups. In this review, we highlight recent trends (e.g., analysis of social networks, decoding race and social groups, and the use of naturalistic stimuli) and discuss several theoretical challenges that arise from the application of these new methods to the question of how the brain represents knowledge about the self and others. This article is categorized under: Neuroscience > Cognition.

Motivation Modulates Brain Networks in Response to Faces Varying in Race and Status: A Multivariate Approach

Previous behavioral and neuroimaging work indicates that individuals who are externally motivated to respond without racial prejudice tend not to spontaneously regulate their prejudice and prefer to focus on nonracial attributes when evaluating others. This fMRI multivariate analysis used partial least squares analysis to examine the distributed neural processing of race and a relevant but ostensibly nonracial attribute (i.e., socioeconomic status) as a function of the perceiver's external motivation. Sixty-one white male participants (Homo sapiens) privately formed impressions of black and white male faces ascribed with high or low status. Across all conditions, greater external motivation was associated with reduced coactivation of brain regions believed to support emotion regulation (rostral anterior cingulate cortex), introspection (middle cingulate), and social cognition (temporal pole, medial prefrontal cortex). The reduced involvement of this network irrespective of target race and status suggests that external motivation is related to the participant's overall approach to impression formation in an interracial context. The findings highlight the importance of examining network coactivation in understanding the role of external motivation in impression formation, among other interracial social processes.

Neuroimaging of person perception: A social-visual interface

The visual system is able to extract an enormous amount of socially relevant information from the face, including social categories, personality traits, and emotion. While facial features may be directly tied to certain perceptions, emerging research suggests that top-down social cognitive factors (e.g., stereotypes, social-conceptual knowledge, prejudice) considerably influence and shape the perceptual process. The rapid integration of higher-order social cognitive processes into visual perception can give rise to systematic biases in face perception and may potentially act as a mediating factor for intergroup behavioral and evaluative biases. Drawing on neuroimaging evidence, we review the ways that top-down social cognitive factors shape visual perception of facial features. This emerging work in social and affective neuroscience builds upon work on predictive coding and perceptual priors in cognitive neuroscience and visual cognition, suggesting domain-general mechanisms that underlie a social-visual interface through which social cognition affects visual perception.

Cognitive control, attention, and the other race effect in memory

People are better at remembering faces from their own race than other races–a phenomenon with significant societal implications. This Other Race Effect (ORE) in memory could arise from different attentional allocation to, and cognitive control over, same- and other-race faces during encoding. Deeper or more differentiated processing of same-race faces could yield more robust representations of same- vs. other-race faces that could support better recognition memory. Conversely, to the extent that other-race faces may be characterized by lower perceptual expertise, attention and cognitive control may be more important for successful encoding of robust, distinct representations of these stimuli. We tested a mechanistic model in which successful encoding of same- and other-race faces, indexed by subsequent memory performance, is differentially predicted by (a) engagement of frontoparietal networks subserving top-down attention and cognitive control, and (b) interactions between frontoparietal networks and fusiform cortex face processing. European American (EA) and African American (AA) participants underwent fMRI while intentionally encoding EA and AA faces, and ~24 hrs later performed an “old/new” recognition memory task. Univariate analyses revealed greater engagement of frontoparietal top-down attention and cognitive control networks during encoding for same- vs. other-race faces, stemming particularly from a failure to engage the cognitive control network during processing of other-race faces that were subsequently forgotten. Psychophysiological interaction (PPI) analyses further revealed that OREs were characterized by greater functional interaction between medial intraparietal sulcus, a component of the top-down attention network, and fusiform cortex during same- than other-race face encoding. Together, these results suggest that group-based face memory biases at least partially stem from differential allocation of cognitive control and top-down attention during encoding, such that same-race memory benefits from elevated top-down attentional engagement with face processing regions; conversely, reduced recruitment of cognitive control circuitry appears more predictive of memory failure when encoding out-group faces.

More Than Meets the Eye: Split-Second Social Perception

Recent research suggests that visual perception of social categories is shaped not only by facial features but also by higher-order social cognitive processes (e.g., stereotypes, attitudes, goals). Building on neural computational models of social perception, we outline a perspective of how multiple bottom-up visual cues are flexibly integrated with a range of top-down processes to form perceptions, and we identify a set of key brain regions involved. During this integration, 'hidden' social category activations are often triggered which temporarily impact perception without manifesting in explicit perceptual judgments. Importantly, these hidden impacts and other aspects of the perceptual process predict downstream social consequences - from politicians' electoral success to several evaluative biases - independently of the outcomes of that process.

Learning Race from Face: A Survey

Faces convey a wealth of social signals, including race, expression, identity, age and gender, all of which have attracted increasing attention from multi-disciplinary research, such as psychology, neuroscience, computer science, to name a few. Gleaned from recent advances in computer vision, computer graphics, and machine learning, computational intelligence based racial face analysis has been particularly popular due to its significant potential and broader impacts in extensive real-world applications, such as security and defense, surveillance, human computer interface (HCI), biometric-based identification, among others. These studies raise an important question: How implicit, non-declarative racial category can be conceptually modeled and quantitatively inferred from the face? Nevertheless, race classification is challenging due to its ambiguity and complexity depending on context and criteria. To address this challenge, recently, significant efforts have been reported toward race detection and categorization in the community. This survey provides a comprehensive and critical review of the state-of-the-art advances in face-race perception, principles, algorithms, and applications. We first discuss race perception problem formulation and motivation, while highlighting the conceptual potentials of racial face processing. Next, taxonomy of feature representational models, algorithms, performance and racial databases are presented with systematic discussions within the unified learning scenario. Finally, in order to stimulate future research in this field, we also highlight the major opportunities and challenges, as well as potentially important cross-cutting themes and research directions for the issue of learning race from face.