An fMRI investigation of racial paralysis

Nature Neuroscience, 2003

We investigated whether individual differences in racial bias among white participants predict the recruitment, and potential depletion, of executive attentional resources during contact with black individuals. White individuals completed an unobtrusive measure of racial bias, then interacted with a black individual, and finally completed an ostensibly unrelated Stroop colornaming test. In a separate functional magnetic resonance imaging (fMRI) session, subjects were presented with unfamiliar black male faces, and the activity of brain regions thought to be critical to executive control was assessed. We found that racial bias predicted activity in right dorsolateral prefrontal cortex (DLPFC) in response to black faces. Furthermore, activity in this region predicted Stroop interference after an actual interracial interaction, and it statistically mediated the relation between racial bias and Stroop interference. These results are consistent with a resource depletion account of the temporary executive dysfunction seen in racially biased individuals after interracial contact.

Journal of Cognitive Neuroscience, 2011

We used fMRI to examine the neural responses that occur during experiences of perceived racial discrimination. Previous neuroimaging studies have focused exclusively on the processes underlying racial bias from the perpetrator's perspective and have yet to examine the processes that occur when individuals are being discriminated against. To extend this work, we examined the neural correlates associated with attributing negative social treatment to racial discrimination to explore the cognitive and affective processes that occur as discrimination is being experienced. To do this, we scanned Black participants while they were ostensibly excluded by Whites and then measured distress levels and race-based attributions for exclusion. In response to being socially excluded by Whites, Black participants who appeared to be more distressed showed greater social pain-related neural activity and reduced emotion regulatory neural activity. In addition, those who attributed exclusion to raci...

Those who are high in external motivation to respond without prejudice tend to focus on non-racial attributes when describing others (Norton, Sommers, Apfelbaum, Pura, & Ariely, 2006). This fMRI study examined the neural processing of race and an alternative yet stereotypically relevant attribute (viz., socioeconomic status: SES) as a function of the perceiver’s external motivation to respond without prejudice (EMS). Sixty-one White participants privately formed impressions of Black and White faces ascribed with high or low SES. Analyses focused on regions supporting race- and status-based reward/salience (NAcc), evaluation (VMPFC), and threat/relevance (amygdala). Consistent with previous findings from the literature on status-based evaluation, we observed greater neural responses to high-status (vs. low-status) targets in all regions of interest when participants were relatively low in EMS. In contrast, we observed the opposite pattern when participants were relatively high in EMS. Notably, all effects were independent of target race. In summary, White perceivers’ race-related motivations similarly altered their neural responses to the SES of Black and White targets. Specifically, the findings suggest that EMS may attenuate the positive value and/or salience of high status in a mixed-race context. Findings are discussed in the context of the stereotypic relationship between race and SES.

Journal of Cognitive …, 2000

& We used fMRI to explore the neural substrates involved in the unconscious evaluation of Black and White social groups. Specifically, we focused on the amygdala, a subcortical structure known to play a role in emotional learning and evaluation. In Experiment 1, White American subjects observed faces of unfamiliar Black and White males. The strength of amygdala activation to Black-versus-White faces was correlated with two indirect (unconscious) measures of race evaluation (Implicit Association Test [IAT] and potentiated startle), but not with the direct (conscious) expression of race attitudes. In Experiment 2, these patterns were not obtained when the stimulus faces belonged to familiar and positively regarded Black and White individuals. Together, these results suggest that amygdala and behavioral responses to Black-versus-White faces in White subjects reflect cultural evaluations of social groups modified by individual experience. & D

The largely independent neuroscience literatures on race and status show increasingly that both constructs shape how we evaluate others. Following an overview and comparison of both literatures, we suggest that apparent differences in the brain regions supporting race- and status-based evaluations may tap into distinct components of a common evaluative network. For example, perceiver motivations and/or category cues (e.g., perceptual vs. knowledge-based) can differ depending on whether one is processing race and/or status, ultimately recruiting distinct mechanisms within this common evaluative network. We emphasize the generalizability of this social neuroscience framework for dimensions beyond race and status and highlight how this framework raises new questions in the study of prejudice-reduction interventions.

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.

Social Cognitive and Affective Neuroscience, 2006

Previous work has shown differential amygdala response to African-American faces by Caucasian individuals. Furthermore, behavioral studies have demonstrated the existence of skin tone bias, the tendency to prefer light skin to dark skin. In the present study, we used functional magnetic resonance imaging (fMRI) to investigate whether skin tone bias moderates differential race-related amygdala activity. Eleven White participants viewed photographs of unfamiliar Black and White faces with varied skin tone (light, dark). Replicating past research, greater amygdala activity was observed for Black faces than White faces. Furthermore, dark-skinned targets elicited more amygdala activity than light-skinned targets. However, these results were qualified by a significant interaction between race and skin tone, such that amygdala activity was observed at equivalent levels for light-and dark-skinned Black targets, but dark-skinned White targets elicited greater amygdala activity than light-skinned White targets.

Nature Neuroscience, 2005

Functional magnetic resonance imaging (fMRI) was used to examine the nature of amygdala sensitivity to race. Both African-American and Caucasian-American individuals showed greater amygdala activity to African-American targets than to Caucasian-American targets, suggesting that race-related amygdala activity may result from cultural learning rather than from the novelty of other races. Additionally, verbal encoding of African-American targets produced significantly less amygdala activity than perceptual encoding of African-American targets.

Perspectives on Psychological Science

We review emerging research on the psychological and biological factors that underlie social group formation, cooperation, and conflict in humans. Our aim is to integrate the intergroup neuroscience literature with classic theories of group processes and intergroup relations in an effort to move beyond merely describing the effects of specific social out-groups on the brain and behavior. Instead, we emphasize the underlying psychological processes that govern intergroup interactions more generally: forming and updating our representations of “us” and “them” via social identification and functional relations between groups. This approach highlights the dynamic nature of social identity and the context dependent nature of intergroup relations. We argue that this theoretical integration can help reconcile seemingly discrepant findings in the literature, provide organizational principles for understanding the core elements of intergroup dynamics, and highlight several exciting directions for future research at the interface of intergroup relations and neuroscience.