Providing regular financial support to low-income mothers can have a dramatic impact on their babies’ brain activity, according to new research in the Proceedings of the National Academy of Sciences.

After recording the neural activity of hundreds of one-year-olds, the study authors found that those whose mothers had received larger monthly cash payments displayed more high-frequency brainwaves, associated with greater cognitive abilities, compared to those who received a smaller sum.

The study presents data from a major randomized control trial called Baby’s First Years, investigating how welfare support can mitigate the adverse effects of poverty on infant brain development.

A total of 1,000 new mothers from low-income backgrounds were recruited to participate in the study, although the difficulties imposed by the COVID-19 pandemic meant that the researchers were only able to record the brain activity of 435 babies one year after birth.

Mothers were all randomly assigned to receive either a monthly payment of $333 or $20 a month immediately after giving birth. Funded by charitable donations, these payments will continue to be delivered until the children are four years and four months old.

"We have known for many years that growing up in poverty puts children at risk for lower school achievement, reduced earnings, and poorer health," explained study author Kimberly Noble in a statement.

"However, until now, we haven't been able to say whether poverty itself causes differences in child development, or whether growing up in poverty is simply associated with other factors that cause those differences."

Using electroencephalography (EEG) to measure infants’ brain activity a year after being born, the researchers found that those in the high-cash gift group displayed greater high-frequency brainwaves in the alpha, beta and gamma bands than those in the low-cash gift group.

“The resultant brain activity patterns have been shown to be associated with the development of subsequent cognitive skills,” the authors explain in the paper, adding that high-frequency brainwaves are linked to better language capabilities and enhanced social and emotional processing.

“All healthy brains are shaped by their environments and experiences, and we are not saying that one group has 'better' brains,” says Noble. “But, because of the randomized design, we know that the $333 per month must have changed children's experiences or environments, and that their brains adapted to those changed circumstances."

The authors, therefore, conclude that welfare payments do indeed bring about changes in babies’ neural activity patterns, although more work is needed in order to determine which experiences in particular mediate the link between greater material wealth and brain development.

Over the coming years, the researchers plan to investigate how mothers spent their extra money and how this influenced family relationships and household stress.

It’s also important to note that it is not yet known if the neural activity noted in this study will actually influence the mental capacities of any of the children as they grow up. For this reason, the researchers intend to continue monitoring each child to determine whether these early alterations persist beyond the first year, and how this may affect their cognitive and behavioral development.