Functional MRI was used to identify the brain areas underlying automatic beliefs about gender and race, and suppression of those attitudes. Participants (n = 20; 7 females) were scanned at 3 tesla while performing the Implicit Association Test (IAT), an indirect measure of race and gender bias. We hypothesized that ventromedial prefrontal cortex areas (PFC) would mediate gender and racial stereotypic attitudes, and suppression of these beliefs would recruit dorsolateral prefrontal cortex (DLPFC) and the anterior cingulate cortex (ACC). Performance data on the IAT revealed gender and racial biases. Racial bias was correlated with an explicit measure of racism. Results showed activation of anteromedial PFC and rostral ACC while participants implicitly made associations consistent with gender and racial biases. In contrast, associations incongruent with stereotypes recruited DLPFC. Implicit gender bias was correlated with amygdala activation during stereotypic conditions. Results suggest there are dissociable roles for anteromedial and dorsolateral PFC circuits in the activation and inhibition of stereotypic attitudes.

These findings of deficits in social perception after damage to the orbitofrontal cortex extend previous clinical and experimental evidence of damage-related impairment in other aspects of social cognition, such as the ability to accurately evaluate emotional facial expressions. In addition, the results suggest that the dorsolateral prefrontal cortex is recruited when inferences about social interactions are made on the basis of nonverbal information.

Patients with damage to the frontal lobes frequently exhibit impaired social behavior, but it is not clear which specific processes are disrupted. The authors investigated the ability to interpret nonverbal emotional expression in patients with lesions involving ventromedial (N=20) or dorsolateral prefrontal cortex (N=9) and in healthy volunteers (N=23). As hypothesized, only patients with ventromedial prefrontal lesions showed impaired task performance relative to normal comparison subjects. These results suggest that deficits in social knowledge, namely difficulty interpreting nonverbal emotional expression, contribute to the aberrant social behavior observed following ventromedial prefrontal cortex lesions.

Patients with damage to the frontal lobes frequently exhibit impaired social behavior, but it is not clear which specific processes are disrupted. The authors investigated the ability to interpret nonverbal emotional expression in patients with lesions involving ventromedial (N=20) or dorsolateral prefrontal cortex (N=9) and in healthy volunteers (N=23). As hypothesized, only patients with ventromedial prefrontal lesions showed impaired task performance relative to normal comparison subjects. These results suggest that deficits in social knowledge, namely difficulty interpreting nonverbal emotional expression, contribute to the aberrant social behavior observed following ventromedial prefrontal cortex lesions.