Poverty may have direct implications for important, early steps in the development of the brain, saddling children of low-income families with slower rates of growth in two key brain structures.
“We are very glad we could contribute to this sobering study about the impact of poverty on early childhood brain development.”
That’s the conclusion of a new study by researchers at the University of Wisconsin-Madison and the University of North Carolina School of Medicine, published online Dec. 11, 2013 by the journal, PLOS ONE.
“We are very glad we could contribute to this sobering study about the impact of poverty on early childhood brain development. We’ve known that poverty can have long lasting consequences for childhood development and learning, and this study provides concrete evidence that poverty can change how the brain itself grows,” said John H. Gilmore, MD, a co-author of the study and professor of psychiatry at UNC.
Jamie Hanson, a graduate student at UW-Madison, is the study’s lead author. Senior authors of the study from UW-Madison are Seth Pollak, PhD, professor of psychology, and Barbara Wolfe, PhD, professor of economics, population health sciences and public affairs.
By age 4, children in families living with incomes under 200 percent of the federal poverty line have less gray matter — brain tissue critical for processing of information and execution of actions — than kids growing up in families with higher incomes.
The study used brain scans provided by the National Institute of Health’s MRI Study of Normal Brain Development. The Early Brain Development research team at UNC including Gilmore, Dinggang Shen, PhD, and Feng Shi, PhD, analyzed these scans using a method they developed for measuring children’s brain volumes. This is an especially difficult technological feat when performed on small and rapidly growing infant brains. Both Shen and Shi are faculty in the UNC Department of Radiology. They and Gilmore are also members of the UNC Biomedical Research Imaging Center (BRIC).
Data from the MRI Study of Normal Brain Development excludes children whose brain development may have been altered by a number of factors: mothers who smoke or drank during pregnancy, birth complications, head injuries, family psychiatric history and other issues. As a result, the findings may underestimate the actual deficit developed by a more representative sample of children from poor families.
The study found no meaningful difference in gray matter between children of middle-income families and those from relatively wealthy ones.
For poor families — who ranged from extremely poor with almost no cash income to a few tens of thousands of dollars per year — the list of potential environmental factors is lengthy. Poor nutrition and lack of sleep, lack of books and other educational toys, parental stress, an unsafe environment, limited enriching conversation are just a few of the potential contributors.