Poverty shrinks kids’ brains.

Nature measures the price of poverty, and the effect it has on children. A bi-coastal study has found that poverty shrinks kids’ brains from birth:

…A team led by neuroscientists Kimberly Noble from Columbia University in New York City and Elizabeth Sowell from Children’s Hospital Los Angeles, California… imaged the brains of 1,099 children, adolescents and young adults in several US cities. Because people with lower incomes in the United States are more likely to be from minority ethnic groups, the team mapped each child’s genetic ancestry and then adjusted the calculations so that the effects of poverty would not be skewed by the small differences in brain structure between ethnic groups.

The brains of children from the lowest income bracket — less than US$25,000 — had up to 6% less surface area than did those of children from families making more than US$150,000, the researchers found. In children from the poorest families, income disparities of a few thousand dollars were associated with major differences in brain structure, particularly in areas associated with language and decision-making skills. Children’s scores on tests measuring cognitive skills, such as reading and memory ability, also declined with parental income.

[Martha Farah, a cognitive neuroscientist at the University of Pennsylvania in Philadelphia,] and her colleagues plan to continue to observe these infants for two years and watch how their brain’s surface area change over time. They also plan to visit the infants’ homes in the hopes of pinpointing factors that might contribute to the differences, such as how many stimulating toys they have and how much attention they get from their parents.

Neither study explains the cause of the cognitive differences. Although the authors of both studies admit that genetic factors could be involved, they suspect that environmental exposures such as stress and nutrition are more important and begin even before the babies are born.