An emerging trend in social neuroscience is to precisely quantify decisions by combining classic behavioral economic paradigms with neuroscience to model individual differences in decision variables that give rise to our judgments in social contexts. Examining intergroup decision-making allows researchers to better understand why and when discrimination occurs in everyday interactions and, importantly, provides insight into the mechanisms of prejudice and prejudice reduction. In my research on social decision-making, I seek to model the complexity of intergroup behaviors by employing tools of neuroeconomics and judgment and decision-making.
Processes that influence discrimination
I investigate a variety of processes that influence discrimination, including perception, implicit and explicit attitudes, and attributions. I extend my basic research on these mechanisms to real-world decision contexts, such as economic decisions and judicial assessments. To explore the processes that influence discrimination, I employ neuroimaging (fMRI and EEG), endocrinology, and lesion mapping methods. From this work, it is clear that social variables rapidly influence our perceptions and evaluations of others (within 120 ms), activate a network of regions involved in emotion and emotion regulation (including the amygdala, VMPFC, DLPFC and ACC), and often require prefrontal cognitive control to down-regulate the influence of social group membership on impressions and decisions.
In recent work, I explore how the attribution process influences discrimination. Attributions are important when assigning legal responsibility and blame. Previous work demonstrates that when explaining the behavior of others, people tend to overweigh dispositional (i.e. character-based explanations) and underweigh situational (i.e. context) explanations for negative outgroup behavior. I hypothesized that overcoming race bias in attributions (incorporating situational information into attributions) should rely on increases in cognitive control mechanisms supported by the prefrontal cortex. Consistent with this prediction, implicit race bias influenced racial bias in attributions and recruitment of DLPFC when incorporating relevant situational information. Moreover, when prefrontal cortical resources are taxed using a physiological stress manipulation or when individuals have DLPFC lesions, dispositional attributions increase. These studies underscore the importance of executive functions in intergroup attributions.
Neuroeconomic approaches to intergroup decision-making
I apply formal economic models to intergroup decision-making. Economic models of intergroup behavior can provide novel insights and facilitate explicit deconstruction of the processes involved. Utilizing the quantitative tools of behavioral economics, I find that racial group membership affects economic decisions, in part by shifting the criteria used in making judgments. I have extended this work to patients with PFC lesions and find that DLPFC lesions increase racial bias in rejection of unfair economic offers. I am beginning to expand this line of inquiry with a project, recently funded by NIA, exploring how group-related social distance of an interaction partner impacts risky decision-making and the neural systems that mediate this relationship. From this work, I find that modeling intergroup decisions allows for a nuanced exploration of the underlying mechanisms and provides novel insights into interventions that can successfully align behavior with intentions.
For example, I am currently building upon my work on attributions to investigate intergroup decision-making. My research on intergroup attributions suggests that when outgroup members behave negatively, people tend to attribute that behavior to their disposition rather than the situation. Given this association, I sought to explore whether individuals punish outgroup members’ negative behavior differently from ingroup members’. To first explore punishment of negative outgroup behavior, I employed the Ultimatum Game and found that participants accept fewer unfair offers from outgroup members compared with ingroup members, especially for individuals high in implicit race bias. To extend this line of inquiry to decisions of guilt, I had 250 community members view a real court case where the defendant varied in race. As with decisions of punishment, implicit bias predicted racial bias in guilt and sentence severity. These real-world decision contexts highlight the importance of an individual differences approach to intergroup decision-making, suggesting that implicit race bias is related to decisions to punish, even when it comes at a personal cost.