The interplay between poverty and the human brain connectome across the lifespan: A systematic review

Living in poverty affects cognitive and emotional functioning. Accumulating research is exploring whether the adverse effects of poverty can be explained by changes in the brain's structural and functional organization. In this systematic review, we synthesize findings on how poverty is associated with changes in structural and functional connectivity across the lifespan. We searched Web of Science, PubMed, and PsycINFO for studies published between 2009 and 2024. Studies were eligible if they examined associations between structural or resting-state functional connectivity and poverty-related measures. In total, 59 studies were included. Structural connectivity findings suggest that poverty during infancy is associated with increased white matter integrity in the cingulum bundle and uncinate fasciculus tracts. However, from childhood onwards, this association reverses, showing decreased integrity in the cingulum bundle, uncinate fasciculus, and superior longitudinal fasciculus. Functional connectivity studies report that poverty is related to reduced connectivity within and between higher-order networks, particularly the default mode, frontoparietal, and cingulo-opercular networks, from childhood through adulthood. Connectivity between the limbic system and higher-order networks shows a negative association in infancy that shifts to a positive association later in life, while the sensorimotor network follows the opposite trajectory. Overall, results indicate that poverty is associated with differences in the connectome. However, the direction and strength of these associations depend on the developmental stage. Potential underlying neurodevelopmental mechanisms and possible future directions are discussed. Clarifying how poverty shapes brain connectivity is essential for developing targeted interventions to address the cognitive and behavioral disparities linked to poverty.