'Talking' brain found better at math

Mathematical calculation requires the two sides of the brain to "talk" to each other, U.S. scientists say, and the stronger the talk, the better the outcome. The research sheds light on the neural basis of human math abilities and suggests possible help for those who suffer from dyscalculia -- an inability to understand and manipulate numbers, the University of Texas at Dallas reported Wednesday. Previous brain imaging studies have shown the right parietal region is primarily involved in basic quantity processing -- like how many socks are in a dresser drawer -- while the left parietal region is involved in more precise numerical operations like addition and subtraction. Scientists had long wondered if the two hemispheres working together could improve math performance, and the new study suggests they can, researchers said. The researchers analyzed brain scans of volunteers as they first performed a simple quantity estimation of objects and then performed simple arithmetic tasks. While the researchers detected the usual left-right task management, they also found communication between the left and right hemispheres increased significantly during the arithmetic tasks compared with the number-counting task. And people who exhibited the strongest connection between hemispheres were the fastest at solving the addition and subtraction problems. Disrupted or inefficient neural communication between the hemispheres may contribute to the impaired math abilities seen in dyscalculia, the numerical equivalent of dyslexia, the researchers said. "If such a causal link exists," lead researcher Joonkoo Park said, "one very interesting avenue of research would be to develop training tasks to enhance parietal connectivity and to test whether they improve numerical competence." Such training might help develop math ability in children and could also help older adults whose arithmetic skills begin to falter as a normal part of age-related cognitive decline, the researchers said.