WASHINGTON – At some point, children quit counting your fingers and just know the answer. Now scientists have put youngsters into brain scanners to find out why, and watched how the brain reorganizes itself as kids learn math.
The take-home advice: drilling your kids on simple addition and multiplication may pay off.
“Experience really does matter,” said Dr. Kathy Mann Koepke of the National Institutes of Health, which funded the research.
Healthy children start making that switch between counting to what’s called fact retrieval when they’re 8 to 9 years old, when they’re still working on fundamental addition and subtraction. How well kids make that shift to memory-based problem-solving is known to predict their ultimate math achievement.
But why do some kids make the transition easier than others?
To start finding out, Stanford University researchers first peeked into the brains of 28 children as they solved a series of simple addition problems inside a brain-scanning MRI machine.
No scribbling out the answer: The 7- to 9-year-olds saw a calculation — three plus four equals seven, for example — flash on a screen and pushed a button to say if the answer was right or wrong. Scientists recorded how quickly they responded and what regions of their brain became active as they did.
The children were tested twice, roughly a year apart. As the kids got older, their answers relied more on memory and became faster and more accurate, and it showed in the brain. There was less activity in the prefrontal and parietal regions associated with counting and more in the brain’s memory center, the hippocampus, the researchers reported Sunday in Nature Neuroscience.
The hippocampus is sort of like a relay station where new memories come in — short-term working memory — and then can be sent elsewhere for longer-term storage and retrieval. Those hippocampal connections increased with the children’s math performance.
But that’s not the whole story.
Next, Dr. Vinod Menon, the study’s senior author, and his team put 20 adolescents and 20 adults into the MRI machines and gave them the same simple addition problems. It turns out that adults don’t use their memory-crunching hippocampus in the same way. Instead of using a lot of effort, retrieving six plus four equals 10 from long-term storage was almost automatic, Menon said.
In other words, the brain became increasingly efficient at retrieving facts over time.
“The study provides new evidence that this experience with math actually changes the hippocampal patterns, or the connections. They become more stable with skill development,” NIH’s Mann Koepke explained. “So learning your addition and multiplication tables and having them in rote memory helps.”
IN FIVE EASY PIECES WITH TAKE 5