Study: Poverty affects children's brains but public policy can reduce impact

A recent study out of Harvard University suggests that public policies aiming to reduce the harms of poverty may lead to larger brains in children. Scientists say that underscores the need for a strong social safety net.

Researchers looked at brain images from 11,000 children in 17 different states that offer a range of health benefits and cash assistance to low income families.

On average, they found children in states with generous benefits had a larger hippocampus, the section of the brain involved in learning, memory and emotion processing. They also had fewer mental health and behavioral problems.

Harvard psychologist Kate McLaughlin said scientists have long found an association between poverty and brain size.

“The question we had is whether the magnitude of that association — so how much [connection] growing up in a family that's living in poverty has on a child's brain development varies based on where you live,” McLaughlin said.

She said the research team found almost a 40% difference in brain size among low-income children living in states with the most generous benefits, such as California, versus the least generous, like Oklahoma. That was after accounting for cost of living.

“Could you use effective public policies to try to reduce the impact of poverty on children's brain development?” she said. “The answer seems to be yes.”

Researchers noted there could be other explanations. For instance, states with generous benefits may also invest more in education, and perhaps that impacts brain development. But they tried to control for most factors.

At the same time, another researcher, David Weissman, said the findings should not be interpreted to mean it’s inevitable that children living in poverty have damaged brains.

"These are really changeable, including by the public policies that we put in place that make things easier and less stressful and more financially manageable for families,” Weissman said.

Although Massachusetts was not part of the study, some Massachusetts-based providers say the findings ring true.

Janelle Matrow is a speech and language specialist at ServiceNet, a Northampton-based agency that provides services to young children with developmental delays. Matrow said one risk factor for those delays is poverty, and the stress hormones that build up and affect focus and attention for both children and parents.

“Of course, there's the issue of access to resources,” Matrow said. “But I think we don't always pay enough attention to how stress affects brain development and how it affects parenting, because you want to be present in order to help your child to learn.”

Prity Shaw directs ServiceNet's early intervention program. She said parents struggling to pay the bills have less time to read to their children or take them out for brain-enriching activities, even the playground. State-funded child care or Head Start can make a big difference.

“It provides a more enriched environment where they're having opportunities for socialization,” Shaw said. “They're having a larger play space, so they have more opportunity to move. They have lots of different toys and experiences for the child.”

And while Massachusetts has better access to health care than many other states, Shaw would still like to see more benefits in general, from additional child care vouchers to more food assistance.

Harvard's Kate McLaughlin said she hopes studies like hers will convince policy makers to make those investments. She said pointing to data on brain size often makes a bigger impression than simply showing developmental differences among children.

"Most policymakers would say, ‘Well, you know, that could just be the individual family not using the right discipline strategies,’” McLaughlin said. “In my experience, people have a harder time pretending that these associations aren't meaningful and important when you show them that they're having an impact at a biological level on how children's brains are developing."

At the same time, she said there’s still time to change the relationship between poverty and the brain — through a better social safety net.

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