This research is really troubling.
A 2015 study from Harvard and MIT performed brain imaging on a group of 12- and 13-year-olds, and found those from lower-income families had thinner brain cortex around key intellectual areas. Further, a 2015 study published in Nature Neuroscience, “Family Income, Parental Education and Brain Structure in Children and Adolescents,” analyzed brain surface area — a measure different than cortical thickness — of 1,099 persons from ages 3 to 20 and correlated that with socioeconomic status, representing the largest study of its kind to date. More than two dozen researchers, led by Kimberly G. Noble of Columbia University, performed brain imaging and looked at relationships with household income levels, as well as education levels of the subjects’ parents.
The study found that family income was associated with greater brain surface area, and that the relationship was especially substantial for lower-income children:
“For every dollar in increased income, the increase in children’s brain surface area was proportionally greater at the lower end of the family-income spectrum.”
The researchers could only speculate about the precise reasons for the link between income status and brain structure; they suggested it might stem from “family stress, cognitive stimulation, environmental toxins or nutrition, or from corresponding differences in the prenatal environment.”
The researchers concluded that “policies targeting families at the low end of the income distribution may be most likely to lead to observable differences in children’s brain and cognitive development.” The researchers were careful to note that these differences in the brains of poor children were not “immutable,” and that there were variations within all income categories.
Still, the correlation is profoundly consequential, not just for the children themselves, but for an American future that will require the participation and talent of all of our citizens.
There are all kinds of arguments for a living wage–fundamental fairness, the amelioration of social unrest, the fact that economic growth requires growing the number of consumers with disposable income, the fact that taxpayers end up subsidizing the bottom lines of major companies paying poverty wages. But this research provides another compelling reason to increase the incomes of poor working families.
As a country, we give a lot of lip service to children’s wellbeing. We need to put our money where our mouths are.