Can living in a highly stigmatizing context alter brain development in children? It has not previously been possible to answer this question, because most neuroimaging studies are conducted in a small number of locations, precluding the possibility of linking contextual variation with neural outcomes. In this study, BEST Lab researchers and colleagues overcame this limitation by using data from the Adolescent Brain and Cognitive Development study (N=11,534; M=9.9 years), the first multisite neuroimaging study that provided substantial variability in sociopolitical contexts and that included individual-level measures of stigma among youth. We operationalized structural stigma related to race and ethnicity in each state, which was measured separately for each stigmatized group using objective state-level indicators of social policies (e.g., restrictive immigration policies) and aggregated prejudicial attitudes. We examined whether these indicators of structural stigma were associated with two neural outcomes—hippocampal volume and amygdala reactivity to threat—that are strongly associated with stress exposure. In a pre-registered analysis, we showed that Black and Latinx youth in higher (vs. lower) structural stigma environments have significantly smaller hippocampal volume, controlling for total intracranial volume, demographics, and family socioeconomic status. The magnitude of the observed difference in hippocampal volume between high and low structural stigma contexts was equivalent to the predicted impact of a $20,000 difference in annual family income in this sample, suggesting that structural stigma may be associated with meaningful changes in brain structure. In contrast, as hypothesized, structural stigma was unrelated to hippocampal volume in non-stigmatized youth, providing evidence of specificity to stigmatized groups. Further, perceived discrimination was unrelated to hippocampal volume among Black and Latinx youth, suggesting that an objective measure of stigma at the contextual level may be more strongly associated with neurodevelopment than subjective perceptions of stigma measured at the individual level. This work not only expands our understanding of the multilevel consequences of stigma, but also suggests that macrolevel features of the social environment are associated with brain structure among youth, which has implications for broadening the range of potential explanatory variables in cognitive neuroscience to include macrosocial influences. 

You can read more about this study in the Journal of the American Academy of Child & Adolescent Psychiatry.