Safety nets support brain development in low-income kids

A new study finds that robust social safety nets such as state-level anti-poverty policies may help mitigate the effects of poverty on children’s brain development.

A new paper in Nature Communications by the Ballmer Institute’s incoming Executive Director Katie McLaughlin and a team at Harvard University looked at the association of family income with the volume of the hippocampus and symptoms of mental health problems in children ages 9 to 11. McLaughlin’s team relied on data gathered in the Adolescent Brain Cognitive Development Study, which follows more than 10,500 youth across 17 states.

The study found that children in low-income families had smaller hippocampal volume and higher levels of anxiety, depression and problem behaviors. Those developmental effects were highest in states with a high cost of living and less generous anti-poverty policies.

The hippocampus plays a major role in learning and memory. During development, the volume of the hippocampus is influenced by environmental experiences, such as chronic stress.

From left: Researchers Mina Cikara, Katie A. McLaughlin and Mark L. Hatzenbuehler
Rrom left: Researchers Mina Cikara, Katie A. McLaughlin and Mark L. Hatzenbuehler

“A smaller hippocampus is a predictor of lower academic achievement,” McLaughlin said. “There is also fairly consistent evidence that kids with smaller hippocampal volume may be more vulnerable to developing mental health problems, especially during adolescence.”

The study points to state-level anti-poverty policies as a major method of mitigating those developmental differences among children. In states with a high cost of living along with more generous cash benefits for low-income families, the socioeconomic disparities in hippocampal volume and mental health problems were smaller, reducing the differences to the level seen in the lowest cost-of-living states, according to McLaughlin and the team’s paper.

“The magnitude of disparities in brain structure is reduced by about a third, while mental health disparities are cut almost in half,” McLaughlin said.

Of all the states included in the study, Oregon had the lowest socioeconomic status-related differences in brain structure.

In Oregon, policies that assist low-income families may be contributing to the reduced effects of poverty on hippocampal volume in children. Oregon has a track record of offering low-cost, reliable access to health care for low-income families, which reduces the stress otherwise felt by families without access to essential health care for their children.

The Oregon Health Authority first began to coordinate physical and behavioral health care at a lower cost for individuals on the Oregon Health Plan in 2012, signaling the start of coordinated care organizations for the state. Oregon is the first state to provide continuous Medicaid/Child Health Insurance Program coverage from birth to a child’s 6th birthday through the 1115 waiver approved in 2022. That means uninterrupted and reliable coverage during the key developmental years of wellness visits for Oregon children.

“Oregon has implemented numerous policies to support children and families with low income by ensuring access to food and high-quality medical care and preschool,” McLaughlin said. “It’s the first state to provide continuous medical coverage for children from low-income families across the first six years of life. This robust social safety net for low-income families is one reason we may see smaller socioeconomic disparities in children’s brain development in Oregon relative to other states."

Oregon also offers the Pandemic-EBT program, which is a direct assistance program helping families purchase food if children within the family are eligible for federal school meal benefits through either SNAP certification, or if their school was a Community Eligible Provision school during the COVID-19 pandemic.

McLaughlin’s team hopes to continue its work by studying how changes in social safety net policies in the study states contribute to future changes in socioeconomic disparities in children’s brain structure and mental health.

—By Victoria Sanchez, The Ballmer Institute for Children's Behavioral Health
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