Children living in poverty-stricken neighborhoods tend to have lower cognitive performance and volume in multiple brain regions, suggesting that the neighborhood context should be considered in studies of poverty and adversity in early life, such as those in JAMA Network Open published study results.
In this cross-sectional study, Washington University researchers attempted to assess the link between poverty and poor cognitive outcomes. For this purpose, they analyzed a basic sample of patients from the ongoing ABCD study (Adolescent Brain Cognitive Development) with 21 locations. The cohort included 11,875 children from the United States, ages 9 or 10, from mostly urban and suburban areas.
The study researchers considered neighborhood poverty and household socioeconomic status as possible factors related to sub-tests of the National Institutes of Health Toolbox’s Cognitive Battery, as well as the hippocampal and prefrontal (dorsolateral prefrontal cortex) [DLPFC]dorsomedial PFC [DMPFC], upper frontal gyrus [SFG]) Volume based on brain scans. The final neighborhood poverty aggregate comprised 9 of 17 values in the Area Deprivation Index.
Greater neighborhood poverty was significantly associated with a lower score for all cognitive domains (overall composition of neighborhood poverty, β = -0.18; 95% CI, -0.21 to -0.15; P <0.001). In addition, there was greater neighborhood poverty with a reduced brain volume in the DLPFC (β = -0.09; 95% CI, -0.12 to -0.07; P <0.001), DMPFC (β = -0.07; 95% CI, -0.09) connected to -0.05; P <0.001), SFG (β = -0.05; 95% CI, -0.08 to -0.03; P <0.001) and right hippocampus (β = -0.04; 95% CI, -0, 06 to - 0.01; P = 0.01).
In addition, the study researchers found a relationship between higher household income and higher scores for all cognitive areas (overall composition for household income, β = 0.30; 95% CI, 0.28-0.33; P <0.001). There was also a significant association between higher household income with greater volume in the right (β = 0.04; 95% CI, 0.02-0.07; P <0.001) and the left hippocampus (β = 0.06; 95% CI, 0.04-0.08; P <0.001), right (β = 0.08; 95% CI, 0.06-0.1; P <0.001) and left SFG (β = 0.07 ; 95% CI, 0.05-0.09; P <0.001), right (β = 0.08; 95% CI, 0.06-0.1; P <0.001) and left DLPFC (β = 0, 07; 95% CI, 0.06-0.09; P <0.001) and right (β = 0.07; 95% CI, 0.05) -0.09; P <0.001) and on the left DMPFC (β = 0.07; 95% CI, 0.05-0.08; P <0.001).
Prefrontal regions have been linked to neighborhood poverty levels, particularly with regard to visual vocabulary (estimate) [SE]-0.03 [0.01];; P <0.001) and oral reading (estimate [SE], -0.02 [0.01];; P <0.001) in addition to episodic memory (estimate [SE], -0.01 [0.004];; P = 0.008). Hippocampal regions have also been associated with neighborhood poverty associations with image vocabulary (estimate [SE], -0.01 [0.004];; P <0.001) and episodic memory (estimate [SE], -0.01 [0.004];; P <0.01).
Limitations of the study were the cross-sectional design and the inclusion of only neighborhood variables, which focus on socio-economic status rather than other indicators of neighborhood poverty such as litter, access to green spaces and the number of grocery stores.
Based on their findings, the researchers suggested that future research should include neighborhood variables “in models of how early living environments are associated with brain maturation and cognitive outcomes that may influence the types of interventions offered to children from disadvantaged backgrounds will”.
Taylor RL, Cooper SR, Jackson JJ, Barch DM. Assessment of neighborhood poverty, cognitive function, and prefrontal and hippocampal volume in children. JAMA Netw Open. Published online on November 3, 2020. doi: 10.1001 / jamanetworkopen.2020.23774