Summary: A 17-year longitudinal study found that children raised in poverty had smaller volumes in several subcortical brain regions—such as the hippocampus, caudate, putamen, and thalamus—and showed reduced growth in these areas over time.
Source: WUSTL
Children who grow up in poverty face higher risks of cognitive and behavioral challenges compared with their more advantaged peers. While prior research has documented many of the physical and mental health disparities tied to socioeconomic disadvantage, Deanna Barch, chair and professor in the Department of Psychological & Brain Sciences at Washington University in St. Louis, and Joan Luby, MD, Professor of Child Psychiatry, led a prolonged inquiry to determine how early poverty relates to outcomes as children move into adulthood—and whether brain development helps explain those links.
To answer these questions, the research team followed 216 preschoolers and their primary caregivers for 17 years, tracking a wide range of developmental, cognitive, social and psychiatric outcomes. Children were first enrolled at ages three to five and were assessed annually. Beginning at age 16, participants completed evaluations of cognitive function, psychiatric status, high-risk behaviors, educational achievement and social functioning. Over the study period each person received up to five structural brain scans, allowing investigators to examine how early socioeconomic status (SES) related to trajectories of brain growth.
The results, published July 14 in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, show that early childhood poverty continues to predict poorer outcomes across multiple domains well into early adulthood—even when families’ socioeconomic circumstances change later in development.
“Yes,” Barch said, “early poverty sadly continues to predict worse outcomes in cognitive, social, educational and behavioral domains.” The study found that these associations are, at least in part, mediated by differences in brain development that are detectable across adolescence and into early adulthood.
Specifically, children who lived below the poverty line as preschoolers showed smaller volumes in several subcortical structures—most notably the hippocampus, caudate, putamen and thalamus—and also exhibited slower growth in those regions over time. As Barch explains, subcortical structures serve as important relay points that route information to cortical regions responsible for higher-order cognitive and emotional processes. Because these structures guide the flow of information across the brain, changes in their development can affect broad cognitive and behavioral outcomes.
Environmental factors linked to poverty—chronic stress, limited access to nutritious food, reduced health care access, and greater exposure to pollutants—likely contribute to altered neural development in these sensitive brain regions. The thalamus, for example, is a central relay that coordinates information flow from lower brain regions to cortical areas; disruption to its development can therefore influence many aspects of cognition and behavior.
Importantly, the study does not present a deterministic view. Many children raised in poverty still achieve positive outcomes, often thanks to protective factors such as supportive caregivers, targeted interventions, and improved economic resources. Barch emphasized that prevention and mitigation matter: policies and programs that reduce childhood poverty could help prevent downstream impacts on brain development and long-term functioning. To test this idea directly, she and colleagues plan to study whether policy changes—such as expansions of child tax credits or other economic supports—can improve developmental trajectories.
Methodologically, the study benefitted from its prospective design and repeated neuroimaging. Participants were recruited from a cohort enriched for early depressive symptoms so researchers could disentangle the effects of early psychopathology from those of poverty itself. Family income-to-needs ratios measured when children were three to five years old served as the primary SES indicator. Brain scans across five waves were processed using a longitudinal pipeline to estimate cortical and subcortical gray matter volumes and growth slopes. Cognitive assessments used standardized tools, and clinicians administered diagnostic interviews alongside parent and youth reports for behavioral and social outcomes.
After controlling for preschool psychopathology and significant life events across the study period, lower preschool SES remained associated with poorer cognitive performance, increased high-risk behaviors, and lower educational and social functioning in early adulthood. Statistical analyses indicated that reduced subcortical gray matter volume and its slower growth mediated some of the observed relationships between early SES and later cognitive and behavioral outcomes.
These findings add to a growing body of evidence that early environmental conditions shape neural development in ways that influence lifelong health, learning, and behavior. They underscore the public health importance of preventing childhood poverty and supporting families early in life to promote healthy brain development and reduce disparities in long-term outcomes.
About this neurodevelopment research news
Source: WUSTL
Contact: Brandie Jefferson – WUSTL
Image: The image is in the public domain
Original Research: Closed access. “Early Childhood Socioeconomic Status and Cognitive and Adaptive Outcomes at the Transition to Adulthood: The Mediating Role of Gray Matter Development Across 5 Scan Waves” by Luby, Barch et al., Biological Psychiatry: CNNI
Abstract
Early Childhood Socioeconomic Status and Cognitive and Adaptive Outcomes at the Transition to Adulthood: The Mediating Role of Gray Matter Development Across 5 Scan Waves
Background
Low early-life socioeconomic status is linked to poorer outcomes in childhood that often persist into adulthood. Determining how early SES influences brain development—and whether those neural changes mediate later cognitive, social, academic and psychiatric outcomes—is critical. This study leverages a unique 17-year longitudinal dataset with five waves of structural brain imaging to examine prospective links between preschool SES and early-adult functioning.
Methods
A cohort of 216 children (50% female; 47.2% non-white) was recruited from a study of early-onset depression and assessed approximately annually. Family income-to-needs ratios measured at ages 3 to 5 indexed SES. Five waves of structural MRI provided measures of cortical and subcortical gray matter volumes processed with a longitudinal pipeline. At age 16+, cognitive function was measured with the NIH Toolbox, and psychiatric diagnoses, high-risk behaviors, educational outcomes, and social functioning were assessed using clinician interviews and parent/youth reports.
Results
Lower preschool SES predicted worse outcomes in cognition, high-risk behavior, educational attainment, and social functioning (standardized effects |Std.B| = .20–.31, ps <.003). Lower SES was associated with reduced cortical (Std.B = .12, p <.0001) and subcortical gray matter volumes (Std.B = .17, p <.0001), and a shallower increase in subcortical gray matter over time (Std.B = .04, p = .012). Subcortical gray matter volume mediated the relationship between preschool SES and later cognitive and high-risk behavioral outcomes.
Conclusions
These longitudinal data highlight the central role of brain development in explaining how early socioeconomic disadvantage can lead to long-lasting differences in cognitive, behavioral, and adaptive outcomes.