Electric brain stimulation improves maths performance

Applying electrical current to the brain can enhance people’s mathematical abilities for up to six months, according to research by neuroscientists at Oxford University.

The research, published this week in Current Biology, demonstrates for the first time that electrical stimulation can successfully enhance mathematical abilities. It builds on earlier work by Dr Cohen Kadosh of Oxford University and his team that showed that a temporary impairment in the processing of mathematical problems (dyscalculia) can be induced using brain stimulation.

In the new study 15 student volunteers, aged 20-21, were taught symbols that represented different numerical values, and then timed to see how quickly and accurately they could complete a series of mathematical puzzles based on those symbols. Volunteers were given either a placebo or low (1mA) electrical stimuli that ran from right to left, or vice versa, across the parietal lobe – an area of the brain that is crucial for processing mathematical problems.

Those who received stimulation from the right to the left parietal lobe reached a high level of performance in these tasks after a few sessions, whereas those with stimulation from the left to the right parietal lobes significantly underperformed, mirroring the behaviour of 6 year-old children. The placebo group’s results fell somewhere between those of the two groups receiving stimulation. Control tests showed that the effect was specific to the learned symbols and did not affect other cognitive functions.

The tests used included the Stroop test (often used with colours where red is written in green ink for example; here larger values were displayed by smaller images and vice versa) and a mapping test (where the image of a value had to be correctly positioned between two others, similar to accurately placing a 5 halfway between a 1 and a 9 on a line). These are standard tests for assessing mathematical abilities and people with numerical disabilities, or children, consistently achieve low scores on these tests.

In both tasks those given the stimulation from right to left parietal lobes performed best. This group was re-tested six months after having been trained and were found to have maintained a high level of performance.

‘This is the first study from a large scale project funded by the Wellcome Trust that aims to provide ways to improve mathematical abilities in those with learning difficulties,’ said Dr Cohen Kadosh of Oxford University’s Department of Experimental Psychology, who is leading the research. ‘At the moment our work is still experimental, so we are definitely not saying that people should use such techniques to treat children with learning difficulties or anyone else. Much more research is needed before we can even start thinking of this kind of electrical stimulation as a treatment. However, we are extremely excited by the potential of our findings and are now looking into the underlying brain changes.’

Dr Cohen Kadosh added: ‘We’ve shown before that we can induce dyscalculia, and now it seems we might be able to make someone better at maths, so we really want to see if we can help people with dyscalculia, with a possible benefit to the general public. Electrical stimulation is unlikely to turn you into the next Einstein, but if we’re lucky it might be able to help some people to cope better with maths.’

The research looked at influencing newly-learned (rather than existing) mathematical abilities: volunteers were asked to learn new symbols, demonstrate that they had learned them, and then apply this knowledge to solving puzzles involving these symbols. Electrical stimulation was applied at the point when they were learning the symbols. The new research shows that right to left stimulation of the parietal lobe enhances the ability of volunteers to retain and apply this new knowledge to problems for at least six months. Previous work by the team showed that a similar induced impairment effect was short-lived.

The paper ‘Modulating neuronal activity produces specific and long lasting changes in numerical competence’ by Roi Cohen Kadosh and colleagues is published in Current Biology on 4 November 2010. The work was carried out by a team of scientists from Oxford University and University College London.