Electrical stimulation boosts math skills in people with weaker neural links

The strength of certain neural connections can predict how well someone can learn math, and mild electrically stimulating these networks can boost learning, according to a study published on July 1^st in the open-access journal PLOS Biology by Roi Cohen Kadosh from University of Surrey, United Kingdom, and colleagues.

When it comes to cognitive skills like reading and math, early advantages tend to compound over time. Mathematical abilities, however, seem to plateau from childhood to adulthood, raising the possibility that innate brain characteristics might shape academic outcomes independently of external factors like socioeconomic status. To better understand the neurobiology of mathematical learning, the authors measured connection strength between brain regions associated with learning math while 72 participants performed a 5-day math task. While solving math problems that required either calculating a solution or rote memorization, participants received weak electrical stimulation to either the dorsolateral prefrontal cortex (dlPFC), which plays an important role in executive function and calculations; the posterior parietal cortex (PPC), which is associated with memory recall; or a placebo. They also used magnetic resonance spectroscopy to measure two brain chemicals, glutamate and GABA, that hint at the brain's current capacity for learning and change.

The researchers found that stronger baseline connectivity between dlPFC, PPC, and the hippocampus - a region involved in long-term memory and in this context, generalizing algorithms across problems - predicted better math performance when participants were asked to calculate the solution, but not when they memorized it. People with weaker connections between the dlPFC and PPC regions improved at calculation learning after electrically stimulating dlPFC. The authors suggest that these results hint at the viability of using brain stimulation to aid math learning in people struggling with biological disadvantages. The authors also identified a complex relationship between neurochemistry, brain plasticity, and communication between regions associated with executive function and memory. Future studies should more deeply examine these relationships, and test whether a neurostimulation approach like this could help people outside of the lab.

Professor Roi Cohen Kadosh, the lead author of the study and Head of the School of Psychology at the University of Surrey, said, "So far, most efforts to improve education have focused on changing the environment – training teachers, redesigning curricula – while largely overlooking the learner's neurobiology. Yet, a growing body of research has shown that biological factors often explain educational outcomes in mathematics more powerfully than environmental ones. By integrating insights from psychology, neuroscience and education to develop innovative techniques that address these neurobiological constraints, we can help more people reach their potential, broaden access to diverse career pathways and reduce long-term inequalities in income, health and wellbeing."