Researchers have cast doubt on a widely-held belief that connects family income with cognitive development, according to a new study published in Proceedings of the National Academy of Sciences.
A popular theory holds that genes play a larger role in brain development for children from advantaged environments than in those from poorer backgrounds, especially in the United States.
But in the largest study to date using matched birth and school records, the researchers from Northwestern University, Stanford University and the University of Florida found family income won’t necessarily mitigate the effects of genetics on cognitive outcomes.
“While children from higher socio-economic status backgrounds have much better cognitive outcomes on average than those from lower socio-economic status households, genetics appear to matter just as much for both groups,” said Northwestern economist David Figlio, study lead author and dean of the School of Education and Social Policy. “Genes matter. Environment matters. But we find no evidence that the two interact.”
Some studies suggest that the difference in genetic influence between rich and poor families is particularly pronounced in the U.S., but the Florida data, which includes records of siblings and twins, calls this idea into question, the researchers said.
The finding mildly surprised Figlio, but he said it falls in line with his previous work published in American Economic Review, which indicated that heavier babies do better in school. In that study of Florida children, Figlio and his coauthors found that those who were heavier at birth scored higher on math and reading tests in the third to eighth grades, and that the relationship between birth weight and test scores is essentially the same for everybody.
“It’s definitely still true that, from the point of view of test scores, you’d rather be a tiny baby from a wealthy family than a big baby from a poor family,” said Figlio, faculty fellow at Northwestern’s Institute for Policy Research. “But birth weight matters, and it matters for everyone. It seems the same effect is at play here.”
A full understanding of how genes interact with the environment for cognition is more complex and elusive than previously supposed, the researchers said.
“Being able to say that ‘genes’ matter more for this group versus that group is appealing partly for its simplicity,” said study co-author Jeremy Freese of Stanford. “We suspect the truth is more complicated: Some genes may matter more in richer families and other genes may matter in poorer families. There’s no overall characterization.”
Freese emphasized that genetic differences do matter in cognitive development. “But we are still far from understanding how in any useful way,” he said. “Meanwhile, we know poor children face many social disadvantages, and there is much we can do to address those to help promote the flourishing of all children.”
In addition to Figlio and Freese, Krzysztof Karbownik of Northwestern University’s Institute for Policy Research and Jeffrey Roth of the University of Florida, Gainesville, coauthored the study.
Image & Story Credit: Northwestern University
more recommended stories
Early-life screen time linked to reduced physical activity in preschool children
From: The Lancet Child & Adolescent.
From as young as 4, children see males as more powerful than females
Results show that children have early.
Want to become an expert? Here’s the 5 things you need…
Scandinavian psychologists identify five key characteristics.
Research shows puberty changes the brains of boys and girls differently
Findings indicate that there are opposite.
Sharing goals – be careful whom you share with
If you want to achieve a.
Questions during shared book reading with preschoolers need to be more challenging
When it comes to challenging young.
Warning to adults: Children notice everything
Children have learning advantage in some.
Children born to older parents tend to have fewer behaviour problems
According to researchers at The Society.
Art therapy found to reduce stress at school for girls
Research through the University of Washington,.
Creativity is not just for the young, study finds
If you believe that great scientists.