According to researchers at the Universities of Tübingen and Bonn, the brain has neurons that fire specifically during certain mathematical operations. Some neurons are active exclusively during addition and others during subtraction. The results are published in the journal Current Biology.
The researchers benefited from a particular feature of the Department of Epileptology at the University Hospital Bonn, which specializes in surgical procedures on the brains of people with epilepsy. Seizures originate consistently from the same area of the brain. Researchers can measure individual neuron activity via electrodes implanted into the brain near the defective area.
Five women and four men had electrodes implanted in the temporal lobe to record the activity of nerve cells. Doctors then asked them to perform simple arithmetic tasks. When calculating ‘5 plus 3’, addition neurons sprang back into action, whereas for ‘7 minus 4,’ their subtraction neurons did. According to the researchers, the effect was the same when they used mathematical symbols or words.
The study represents an important step towards a better understanding of our ability to calculate with numbers. Results were published as Neuronal codes for arithmetic rule processing in the human brain; DOI: https://doi.org/10.1016/j.cub.2022.01.054