The brains of children from poorer backgrounds are significantly less developed than those of their richer counterparts, a study has found. Those brought up in wealthier homes have bigger brains and greater cognitive skill sets, meaning their advantages reach well beyond simply having nice things.

In the largest study of its kind to date, researchers at The Saban Institute of Children's Hospital Los Angeles and Columbia Medical Center analyzed the brains of 1,099 children, teenagers, and young adults, measuring their brains against socioeconomic factors data such as parental income and family education.

The results showed that income was closely associated with brain surface area, proving a long-held theory that the financial health of a young person’s family directly affects their physical development.

While this has been demonstrated in prior studies pertaining to cognitive functions, where richer children have displayed higher IQ levels and a greater capacity to focus on given tasks, this new research marks its developmental impact.

"Among children from the lowest income families, small differences in income were associated with relatively large differences in surface area in a number of regions of the brain associated with skills important for academic success," explains Dr. Kimberley Noble, the paper's first author.

Those with better-educated parents also had a larger hippocampus: the area responsible for things such as converting short-term memories to the long term, and managing spatial awareness. Families with an annual income of $150,000 were found to produce kids with a 6 percent larger brain than one from a home earning less than $25,000 over the same period.

The areas of the brain noticeably larger across more advantaged children are key to academic success, as well as memory retention, reasoning, and language skills, making their impact on potential prosperity vital. The finding chimes with a 2013 study, which found children from low-income families to have less gray matter—tissue that processes information and executes actions—than others.

Though it’s difficult to pinpoint exact reasons for this disparity, likely causes of superior brain growth include better health care, nutrition, and access to cleaner air—all benefits of environmental factors bestowed upon those able to pay for them.

“While in no way implying that a child’s socioeconomic circumstances lead to immutable changes in brain development or cognition, our data suggest that wider access to resources likely afforded by the more affluent may lead to differences in a child’s brain structure,” says director of the Developmental Cognitive Neuroimaging Laboratory, Elizabeth Sowell, Ph.D.

One of the study’s notable findings was that among the poorest families, even incremental income rises of a few thousand dollars were associated with major changes in the brain’s structure, especially in areas responsible for decision-making.

This has led its researchers to consider their next move—a major trial to investigate whether a monthly stipend could help to stimulate the brain development of children from poor families by ameliorating some of the environmental factors presumed to affect it.

A cohort of low-income mothers will be given either a small or large sum each month to see how this affects their lives: the results of which Noble believes will play a crucial role in informing how financial aid is distributed among poorer families with young children.

“Improving access to resources that enrich the developmental environment could potentially change the trajectories of brain development for the better, even in children and adolescents in the age range we studied,” Sowell adds. The results could prove to be instrumental in amending policy and ensuring that all children in the U.S. are able to share the same educational playing field, irrespective of how much their parents earn.