Children with richer parents have larger brains compared to children with poorer parents, according to a new study. The differences in the brain were most marked in the areas that control language, reading, decision making and memory, the study found.

However, researchers from California also found that community help and teaching can help remedy the disparities found in poorer children. They concluded that factors such as better school lunches and teachers that were motivated can actually have a significant impact on the brain development of these children.

For the study, which claims to be the largest of its kind, researchers from the University of Southern California tested 1,099 people that were developing, both male and female, between the ages of 3 and 20. They measured brain surface area by scans and conducted cognitive test, then compared them to the income levels of their parents, correcting for other potential influences on brain structure, such as genetic characteristics.

Scientists found that not only were there differences between the richest and the poorest, but there were also marked variations at the lower end of the scale. There was a bigger difference between the results of families earning $30,000 and $50,000 a year than there was between $90,000 and $110,000.

Report co-author Elizabeth Sowell said, "It seems reasonable to speculate that resources afforded by the more affluent, such as nutrition, childcare, schools, help 'wire' the brain through development. It is not too late to think about how to impact resources that enrich the developmental environment that in turn help the brain wire itself together."

These findings are in line with another unpublished study conducted by Martha Farah, a cognitive neuroscientist at the University of Pennsylvania in Philadelphia. Farah and her associates scanned the brains of 44 African American girls, each about one month old, from different socioeconomic groups in Philadelphia.

Even at this early age, researchers found that infants in the lower socioeconomic groups had smaller brains compared to their wealthier counterparts.

The studies don't seek to explain exactly why there are differences, but researchers suspect that environmental stress and nutrition are important factors.

"It does make us think the focus should be redirected at gestation and stresses like nutrition and exposure to toxins," says Hallam Hurt, a neonatologist at Children's Hospital of Philadelphia who led the infant research study.

"The most important point we want to convey is not, 'If you are poor, your brain will be smaller, and there is nothing that can be done about it' - that is absolutely not the message," Sowell says.