A recent study published in Psychological Science found a possible connection between cortical development in children and their performance on standardized tests. Children with thicker cortexes did better on these tests, and they were also from higher-income families.
Although the study did not explore the reasons behind these developments, there are a few possibilities. Children from higher-income families tend to have more educational support early in life and face less stress. Meanwhile, children from lower-income families tend to have more stress in their early life, less access to educational materials, and even less access to spoken language early in their development. All of these factors have been previously linked to academic performance, but they might be linked to cortical thickness as well.
In recent years, based on information form standardized test results, there has been a widening performance gap between high- and low-income students. This comes even at a time when gaps are narrowing along racial or ethnic lines. As an increasing number of families in the United States slip further down the economic ladder, this problem could be a growing one.
It’s not all doom and gloom, though. The authors of the study point out that the brain is quite elastic, and these structural differences are not permanent. Just because a child has a less developed cortex by middle school doesn’t mean that they’re stuck with that forever. Finding ways to help students continue to develop their abilities can offset the problem, and hopefully, those problems can be identified and addressed.
The authors are planning a follow up study in which they look at educational plans and programs that have successfully helped to close the performance gap between high- and low-income students. If possible, they want to try and trace cortical thickness as well and see if these programs, or others like them, can help to create some more parity in development.