When it comes to math, MRIs may be better than IQs and even past math scores at showing whether a tutor can help a child master everything from trapezoids to trigonometry.
A new study from the Stanford University School of Medicine says that the size and circuitry of certain parts of childrens brains are excellent predictors of how well theyll respond to intensive math tutoring.
The researchers most surprising finding was that childrens IQ and math scores had no effect on tutoring outcomes, yet brain scan images predicted how much a child would learn, said Vinod Menon, a Stanford professor of psychiatry and behavioral sciences who was senior author of the study, published in the journal Proceedings of the National Academy of Sciences.
Menons research team took MRI scans of 24 third-graders just before they underwent eight weeks of rigorous math tutoring. A control group of children also had their brains scanned, but they didnt get any tutoring.
The kids who were tutored showed across-the-board gains in their arithmetic skills, with the levels of their improvement varying wildly from 8 percent improvement up to 198 percent. The children in the control group showed no signs of improvement.
The researchers found that the kids who responded the best to tutoring tended to have a larger and more active hippocampus.
The hippocampus is known to play an important role in learning and memory. But its role in mastering specific skills like math hadnt been explored until now.
Even more than its size, the hippocampuss ability to get along with other parts of the brain was the biggest predictor of math success.
The type of MRI used by Menons team is called an fMRI (functional magnetic resonance imaging), which measures changes in the flow of oxygenated blood from one part of the brain to another.
Menon believes the tighter the connections between the hippocampus and the prefrontal cortex a part of the brain that influences decision-making and behavior the more rapid the retrieval of stored knowledge.
The fact that a brain scan rather than IQ or math scores could predict how students would respond to tutoring also surprised Michael Posner, a cognitive neuroscientist at the University of Oregon who was not involved in the study.
But Posner is convinced that the variety of very modern imaging methods used by Menon were accurate. Thats one of the main reasons this study is important, he said.
Posner was also surprised by the involvement of the hippocampus, rather than other regions of the brain, in learning math. The hippocampus isnt a system that one wouldve thought specific to mathematics, Posner said.