Passing a weak electrical current through the brain improves people's ability to learn new maths, a study suggests
Schoolchildren who struggle to grasp mathematics could benefit from having their brains zapped with electricity, scientists say.
A study of university students found that gentle electrical stimulation to the rear of the brain boosted their ability to learn and use numbers for up to six months.
The findings could lead to new treatments for children and adults who fail to master mathematics because of learning disabilities, or mental impairments caused by stroke or neurodegenerative disease.
"I am certainly not advising people to go around giving themselves electric shocks, but we are extremely excited by the potential of our findings," said Roi Cohen Kadosh, a neuroscientist at Oxford University.
"We've shown before that we can temporarily induce dyscalculia [a mathematical disability], and now it seems we might also be able to make someone better at maths. Electrical stimulation will most likely not turn you into Albert Einstein, but if we're successful, it might be able to help some people to cope better with maths."
The team at Oxford University and University College London recruited 15 students for the study and divided them into three groups. Each spent six days learning a series of unfamiliar symbols that corresponded to the numbers zero to nine.
The volunteers were given electrical brain stimulation every day, using a technique called transcranial direct current stimulation (TDCS), which passes a continuous, weak current through the brain via electrodes on the scalp. The electrodes were positioned so that the current passed through parts of the brain called the left and right parietal lobes, which are at the back of the head above the ears.
The first group of students was stimulated from the right side of the brain to the left for 20 minutes, while in the second group, the current passed in the other direction. The third group was used as a control and treated for only 30 seconds, a level of stimulation that should not cause any long-term changes in the brain.
The students were given basic number tasks at the end of each day. In one test, they were asked to order the new symbols on a line according to their numerical value. In a second test, participants were shown two symbols at random and asked to say which was the larger of the two. To confuse the students, symbols for low value numbers sometimes appeared in a larger print and vice versa.
The study found remarkable differences in the students' ability to learn and use the new numbering system. After four days, those whose brains had been stimulated from right to left performed as well with the novel numbering system as a typical adult would with normal numbers. But when students' brains were stimulated in the other direction, they performed worse. Students given only 30 seconds of brain stimulation had scores that fell in between the others, according to a report in Current Biology.
Cohen Kadosh said that stimulating the brain from right to left seems to boost learning and memory by making neurons in the right parietal lobe fire more easily. "If you stimulate the brain in that direction, you enhance the function of the right parietal lobe, which seems to be the crucial area for maths," he told the Guardian.
When the students were invited back six months later their performance on the maths tests had not changed, suggesting that the stimulation had a long-term impact on their learning. Cohen Kadosh said that the impaired group fared worse only at learning the new number system, and was not adversely affected in other ways.
"If this looks promising and the side effects are minimal or non-existent, we will try to target a younger group to see if we can eventually have an intervention programme for those who have difficulty with mathematics," said Cohen Kadosh.