By Corynn Greene
We can all agree that one’s socioeconomic background is a definitive factor when it comes to things like their development and education, but according to a recent study conducted by researcher Seth Pollack of the University of Wisconsin–Madison this can be attributed to more than just access (or lack there of) to things like private schools and expensive educational tools. Comparing poverty’s effect on the developmental biology of children to that of lead exposure, he thinks times call for an immediate change.
Past research has shown that poor children have smaller brains and score lower on standardized tests than children who grew up in more comfortable circumstances, but Pollack’s new study, through the statistical analysis of MRI scans from 389 children and teens over six years, confirms a new relationship: Poor kids’ smaller brains are linked to their test score deficit when compared to middle class and rich kids – it’s the delay in brain growth that is accounting for the lower test scores in school.
“This study is not just about having smaller brains – those delays in brain growth are actually statistically explaining the achievement test score difference.” – Pollack
The children used in this study were economically diverse, drawn from six different places in the U.S., and were representative of demographic factors like income, race, and ethnicity. Subjects who were born from risky pregnancies, complicated births, were from families with histories of mental illness and were already exhibiting behavioral or psychiatric issues, or had irregular head sizes at birth were excluded from the study. Pollack looked to find children who started life in similarly healthy states. The MRI scans confirmed that as poor children grew, the areas of the brain that were most susceptible to environmental influence and crucial for academic development had structural differences from middle-class and rich kids. Additionally, the poor kids had less gray matter overall than the more well-off ones – the deficits only getting worse for kids who lived below the federal poverty line.
Using math models to plot the differences, Pollack found that these deficits in the brains of poor kids explained as much as 15 to 20 percent of their poor test achievement. Other professionals in the child development research community such as Greg Duncan of the University of California–Irvine say that Pollack’s findings are scary but unsurprising. “There is an ongoing debate in Congress about whether or not to cut benefit levels in programs like food stamps and the earned income tax credit, and the debate usually centers around whether the parents are lazy or not, but what studies like this suggest is that cutting benefit levels in programs that support low income families may have consequences fro kids’ brain development – that makes it very scary indeed,” said Duncan.
Throughout his study, there was one aspect of Pollack’s research that he did find surprising. He expected the wealth-brain size relationship to increase exponentially, with the wealthiest kids having the biggest brains and highest achievement and the poorest kids with the smallest brains and lowest achievement. Instead he found that there was, “absolutely no differences between middle class kids and affluent kids when it came to brain size or test scores,” meaning that rather than an upward curve the line was more of a step, with poor kids near the bottom and everyone else on a higher level.
“That suggests to me that this isn’t just a function of how much stuff you’ve got. Something is happening to children who are living in severe poverty, and that’s where the brain growth appears to be affected,” said Pollack. To him, this correlational research is strong enough for him to talk about its implications, “My discussion of poverty as a biomedical problem and not a social one seems to unite people on opposite ends of the ideological spectrum on solutions to shield kids from its effects.” He hopes our nation’s politicians and leaders can get behind him and his research as well, “Maybe this helps policymakers and people in communities band together to think about what needs to be done here,” he concluded.