Association for Public Policy Analysis & Management

Children living in poverty have lower scores on standardized tests of academic achievement, poorer grades in school, and lower educational attainment. These patterns persist into adulthood, ultimately contributing to reduced wages and income. Despite the numerous studies demonstrating the relationship between family resources and children’s scholastic success, relatively little is understood about the mechanisms underlying the influence of poverty on children’s skills, learning, and achievement.

We present a novel way to understand this gap between children developing in poverty and their non-impoverished peers: utilizing a unique and extremely rich data source, we investigate the potential mechanistic role of neurobiology. A growing literature in neuroscience demonstrates that environments of poverty – and, particularly, associated inequities in parental nurturance and early life stress – profoundly affect brain architecture and functioning. A significant next step is to quantify the implications of these observed maturational lags for children’s developmental outcomes.

Using a large longitudinal sample of healthy children (newborn through age 22), we first examine the influence of poverty on the relative development of several areas of the brain believed to play an important role in cognitive abilities critical for children’s school readiness including sustained attention, planning, and cognitive flexibility. We then test whether deviations from normative development in these important areas of the brain mediate the well-established relationship between income and achievement.

Brain areas of interest were selected both for their roles in specific cognitive functions and to mitigate concerns that observed differences across socioeconomic groups may reflect some sort of genetic predisposition. We focus on portions of the brain with a protracted period of post-natal development (areas of the brain most likely to be vulnerable to the environment – and socioeconomic status) and, specifically the brains gray matter tissue which prior work suggests is likely affected by the environment and less heritable than other brain tissues.

We report evidence of regionally-specific neurobiological mechanisms though which childhood poverty may convey risk for learning and scholastic success. For example, among children living below 1.5 times the FPL, the relative development of the frontal and temporal lobes may explain up to 15-20 percent of the disparity in general measures of intelligence and academic skills. Additional cognitive and behavioral functions examined include language, memory, executive functioning, and psychosocial function.

With more than half of US public school students living in poverty, the data described in this manuscript has significant and broad implications. Cognitive and noncognitive skills are important determinants for a range of adult outcomes. As such it would appear that, without public policy initiatives aimed at improving and decreasing disparities in human capital, the potential of children developing in poverty may be limited at a young age. However, the sensitivity of the brain to changes in environmental circumstances – positive as well as negative – lends credence to the idea that interventions to remediate adverse early environments may have some success in altering this neurobiological tie.