Perceived Discrimination and Superior Frontal Cortex Surface Area in Children: Sex Differences

Background: Limited knowledge exists on the role of Perceived Discrimination (PD) as a social determinant and risk factor that influences children’s brain development and whether this association is different for male and female children. Aim: To examine the association between PD, the superior frontal cortex, and sex differences in a national sample of 9/10-year-old children in the US. Methods: This cross-sectional study included 8,719 children from the Adolescent Brain Cognitive Development (ABCD) study. The exposure variable was PD, and the outcome variables were the right and left superior frontal cortex surface areas, measured using structural MRIs. Covariates included: age, family structure, parental education, household income, stressful life events, financial stress, neighborhood poverty, and neighborhood toxins/pollutants (lead, PM2.5, and NO2). We used a mixed-effect regression model for data analysis to adjust to the nested nature of the ABCD data. Results: There was an inverse association between PD and superior frontal cortex surface area in children. We found a statistically significant interaction between PD and the superior frontal cortex, indicating a more prominent inverse association between PD and superior frontal cortex surface area in males than females. Similar findings were observed for the right and left hemispheres. Conclusion: High levels of PD may be a more salient determinant of superior frontal cortex surface area for male than female children. Sex may alter the relevance of high PD for the brain development of US children. More research is needed on the mechanism by which sex differences emerge in the association between PD and brain development.