If you’ve ever wondered what’s going on in your child’s brain when he or she has an "aha!" moment doing his math homework, new research suggests that the brain is indeed developing. While we are still far from understanding all the intricacies that take place as the brain does math computations, the new study shows that math training stimulates several key changes that occur in the brain in just a one-year period.

The researchers also saw more "cross-talk" between the two regions in the older kids, which means that the two parts of the brain were exchanging information more readily as kids acquired new math skills.

The study looked at children who had just finished either second or third grade. Those in each age group were asked to do simple or complex math problems. The kids came from a number of different schools, and all were of normal intelligence. The simple math problems involved adding 1 to another number (for example, 4+1=5). The complex problems involved adding a number between 2 and 5 to a number between 2 and 9 (for example, 3+7=10). While they did these problems, their brains were scanned with functional MRI (fMRI) so that the researchers could observe which areas were activated as the kids did math.

The team found significant differences between the two age groups in two important areas of the brain. One of the brain areas is known to be involved in representing numbers or quantities; the other is important in working memory. Both brain regions were more active in the 3rd graders when they computed the complex, vs. the simple, math problems. The researchers also saw more "cross-talk" between the two regions in the older kids, which means that the two parts of the brain were exchanging information more readily as kids acquired new math skills.

The study is important because it looks at such a relatively short time frame. Tracking changes in the brain across a one-year time period is fairly new, and most previous studies had only compared changes between children and teenagers or adults. Understanding what’s happening across shorter time periods could eventually help researchers better diagnose and treat kids with learning disabilities like dyscalculia (problems with math comprehension).

The study was carried out by a team at Stanford University and published in the May 18, 2011 online issue of NeuroImage.