Are Teachers Biased against Black Children? A Study of Race, Amygdala Volume, and Problem Behaviors

Introduction: While the amygdala has a core role in behaviors, less is known about racial variation in the association between amygdala volume and teachers’ behavioral rating of children. According to the Minorities’ Diminished Returns (MDRs) phenomenon, the effects of individual-level risk and protective factors tend to be weaker for Black than White children due to structural factors such as social stratification and racism. Purpose: Built on the MDRs framework and conceptualizing race as a social rather than a biological factor, this study explored racial variation in the magnitude of the effects of amygdala volume on teachers’ behavioral ratings of children. Methods: For this cross-sectional study, we used baseline socioeconomic data and structural magnetic resonance imaging (sMRI) data of 4305 American children ages 9-10 who had participated in the Adolescent Brain Cognitive Development (ABCD) study. The primary outcome was the teachers’ behavioral rating of the child. The independent variable was amygdala volume. Age, sex, parental education, parental marital status, and ethnicity were the covariates. Race was the moderator. We used mixed-effect models for data analysis to adjust for the participants’ nested nature within families and study sites. Results: Teachers rated children with larger amygdala volumes as having lower behavioral problems. The concordance between size of amygdala volume and teachers’ behavioral rating of the child was modified by race. For while children, teachers reported the children to have lower behavioral problems when they had a large amygdala. For Black children, teachers reported high behavioral problems across all amygdala sizes. Conclusions: The results can be explained in two ways. The first explanation is minorities’ diminished returns hypothesis (MDRs). In line with MDRs, due to structural inequalities and school segregation, a large amygdala would result in a more favorable behavioral rating of the White children than Black children, as we expect an unequal effect of equal resources across racial groups in the presence of racism. The second explanation is systemic bias of teachers against Black children: meaning that due to their anti-Black bias, teachers report high behavioral problems in Black children, across all amygdala sizes (behavioral profiles). That means, race may trigger some cues and biases in the teachers, so they do not pay attention to the details of the behavioral profile of the Black child. For White children, however, in the absence of such racial bias, teachers behavioral rating of a child reflects the child’s amygdala size