Socioeconomic disparities are associated with differences in cognitive development. The extent to which this translates to disparities in brain structure is unclear. We investigated relationships between socioeconomic factors and brain morphometry, independently of genetic ancestry, among a cohort of 1,099 typically developing individuals between 3 and 20 years of age. Income was logarithmically associated with brain surface area. Among children from lower income families, small differences in income were associated with relatively large differences in surface area, whereas, among children from higher income families, similar income increments were associated with smaller differences in surface area. These relationships were most prominent in regions supporting language, reading, executive functions and spatial skills; surface area mediated socioeconomic differences in certain neurocognitive abilities. These data imply that income relates most strongly to brain structure among the most disadvantaged children.

The tests showed that participants in the experiment from poor families read worse, concentrate, remember and have less vocabulary. Noble concludes that by the age of two, the differences in the brains of the rich and the poor are noticeable. On average, the cognitive test scores of a child from a family in need will be 60% lower. There is also evidence that financial pressures reduce gray matter and interfere with the connected work of different parts of the brain. In addition, chronic stress negatively affects the functioning of the hippocampus and amygdala, which are responsible for memory and emotional responses.

https://www.nature.com/articles/nn.3983