# Electrical brain boost

**A small dose of electricity to the brain can boost mathematical ability, a new study has found.**

Oxford University researcher Roi Cohen Kadosh and his colleagues, writing in Current Biology, tested the effects on the mathematical prowess of 15 volunteers undergoing a process called TDCS - transcranial direct current stimulation, which involves non-invasively passing a small electrical current through the brain. The stimulus was applied to the parietal lobes (the back part of the brain), the right side of which has previously been shown to be linked to mathematical function, for 20 minutes every day over a 6 day period.

The subjects were then trained to handle a new set of nine "numbers", represented by symbols, the values of which relative to each other the subjects initially did not know. Their task was to learn them. They were assessed using standard maths testing algorithms designed to probe the subjects' understanding of how the numbers related to each other.

The results were intriguing. Subjects in which the right side of the head was connected to the positive electrode did much better on the numerical tests than subjects wired up the other way around who performed worse.

Control participants, who did not receive any real stimulus, fell somewhere between the performances of the two groups. Even more surprising, when the same subjects were re-tested months later and without having received any electrical stimulus in the meantime, those that had benefited from the stimulus initially continued to outperform the others.

According to the Oxford team, up to one person in 5 has significant difficulty handling numbers in their head. This approach, they say, could therefore make a significant contribution to boosting mathematical brain power for the numerically challenged, or just the average joe who wants to buff up his mental arithmetic!

## Comments

## Add a comment