Inequality, brain development, and adolescent mental health and cognition

Understanding typical and atypical neurodevelopment requires attention to the full ecology in which children grow. Anchored in Bronfenbrenner’s ecological framework, this talk will present findings from neuroimaging studies that examine how inequality—at the individual, neighbourhood, and societal levels—shape brain and behaviour development. I will first describe work demonstrating how individual-level socioeconomic resources shape trajectories of structural and functional development to ultimately contribute to differences in cognitive and socio-emotional outcomes. Moving beyond the family, I will highlight evidence that neighbourhood characteristics, including deprivation and access to green spaces, confer independent effects on the brain and behaviour, and that these associations depend on other aspects of children’s environments. In particular, I show that positive parenting practices, school environments, and lifestyle factors can buffer the effects of household and neighbourhood disadvantage on the brain, and that different dimensions of SES jointly shape brain structure and function. Finally, I present new findings that structural factors—namely macroeconomic income inequality—have widespread effects on cortical thickness, surface area, and functional connectivity, even after accounting for individual- and state-level confounders. These neural alterations partially account for elevated risk for later mental health problems among children living in more unequal states. Together, this work demonstrates how environmental influences across multiple levels contribute—independently and jointly—to differences in children’s brain development. Findings underscore the need for policies that strengthen family and school supports, invest in neighbourhoods, and address structural inequality to promote healthy developmental trajectories.