New brain-imaging research provided insight into how children's' brains reorganize themselves when they start learning math.

The longitudinal study revealed a group of brain changes, mainly located in the memory-froming hippocampus, are essential to these reorganizations, Stanford University Medical Center reported.

"We wanted to understand how children acquire new knowledge, and determine why some children learn to retrieve facts from memory better than others," said Vinod Menon, PhD, professor of psychiatry and behavioral sciences and the senior author of the study. "This work provides insight into the dynamic changes that occur over the course of cognitive development in each child."

Past research has revealed children use the hippocampus and the prefrontal cortex much differently than adults when solving math problems.

"It was surprising to us that the hippocampal and prefrontal contributions to memory-based problem-solving during childhood don't look anything like what we would have expected for the adult brain," said postdoctoral scholar Shaozheng Qin, PhD, who is the paper's lead author.

In the recent study 28 children were asked to solve simple math problems whiler eceiving two functional magnetic resonance imaging brain scans conducted about 1.2 years apart. The research team also scanned 20 adolescents and 20 adults.

During the study the children between the ages of 8.2 and 9.4 became more accurate problem solvers and relied more on retrieving math facts from memory and less from counting. The team observed several shifts in the children's brains, primarily in the hippocampus, after only one year; regions involved in counting, such as sections of the prefrontal cortex, appeared less activated. The researchers also saw changes in the degree to which the hippocampus was connected to other parts of the children's brains; sections of the "prefrontal, anterior temporal cortex and parietal cortex" appeared to be more connected to the hippocampus after one year.  

Adults and adolescents proved to use their hippocampus minimally while solving math problems, and instead pulled information from the neocortex.

"What this means is that the hippocampus is providing a scaffold for learning and consolidating facts into long-term memory in children," Menon said.

The team compared the level of variation in brain activity in the different age groups as they correctly solved math problems. They found the brain activity patterns were more stable in adolescents and adults than children, suggesting the brain gets better at solving math problems if subjected to consistant activity. In the future the researchers hope to look at how brain activity differs in children with math-learning disabilities.

"In children with math-learning disabilities, we know that the ability to retrieve facts fluently is a basic problem, and remains a bottleneck for them in high school and college," Menon said. "Is it that the hippocampus can't provide a reliable scaffold to build good representations of math facts in other parts of the brain during the early stages of learning, and so the child continues to use inefficient strategies to solve math problems? We want to test this."

The findings were reported Sunday in Nature Neuroscience.