According to new research released on Monday, Jan. 24, supporting low-income families with cash could protect infants from the damaging effects that poverty has on brain development.

Baby's First Years clinical trial is the first direct study of poverty reduction in the United States to focus on early childhood.

The preliminary findings from the ongoing clinical trial, found that infants whose families received an extra $4,000 in annual income were more likely to show brain activity patterns associated with the development of thinking and learning.

Baby's First Years clinical trial is the first direct study of poverty reduction in the United States to focus on early childhood.

These discoveries come just weeks after the Child Tax Credit, which provided additional money to low-income parents, expired.

Previous research has shown that growing up in poverty impacts brain development, children who grew up in these conditions have lower rates of high school graduation and college attendance. 

But the new study goes deeper, highlighting a link between poverty and brain development. 

“All of the past work has been correlational. We could say based on past work that poverty is related to these differences, but we couldn’t say poverty is causing these differences. From a scientific perspective, the only way to answer that question is through a randomized clinical trial,” Dr. Kimberly Noble, co-author of the study and professor of neuroscience at Columbia University, told NBC News. 

Noble, along with researchers from six universities, recruited low-income women who had recently given birth in New Orleans, New York City, Omaha, Nebraska, and Minnesota’s Twin Cities. 

The mothers, who are mostly Black and Latina, were randomized to receive either a debit card with a monthly gift of $333 or a nominal monthly gift of $20. This amounted to either an extra $3,996 or $240 in annual income. 

By intervening in this way, researchers were able to find out if there is a direct cause-and-effect relationship between cash support for low-income families and childhood development. The larger amount was chosen because it’s a feasible amount that could be included in policies that provide stipends to families living in poverty. 

Throughout four years, the team will make annual visits to the homes to measure the children’s brain activity, have the mothers complete a questionnaire and observe the mother and baby together. 

Proceedings from the first year of the trial were published Monday in the journal Proceedings of the National Academy of Sciences. These findings focused on brain activity in 435 one-year-olds in the study. 

As children grow older, they tend to have faster brain activity, which is associated with the subsequent development of skills necessary for learning. 

The babies in the families that received more money from the study had more of these fast brain waves compared to those in families that received the lower amount. 

“There are windows of opportunity or vulnerability when the brain changes in response to the psychosocial environment. It’s important to enrich, not deprive, children during these crucial periods of time,” said Dr. Joan Luby, a Samuel and Mae S. Ludwig professor of child psychiatry at the Washington University School of Medicine in St. Louis. 

The research team is currently working to collect more information on how the money was spent and what circumstances may have contributed to the changes in brain activity. 

But because the trial was randomized and controlled, “we know that the $333 per month must have changed children’s experiences or environments, and that their brains adapted to those changed circumstances,” Noble told NBC News. 

The Child Tax Credit, which provided low-income families with up to $300 a month per child, expired Jan. 14, and the Senate has been unable to come to an agreement on whether to extend the support. 

While renewal of the tax credit is uncertain, Luby believes the study should inform Congress on the “tremendous importance” of it.