"This is exciting and a little scary," said Henry Greely who played no role in the study but is familiar with its contents, in a news release. "It demonstrates, first, that we can see when someone's dealing with numbers and, second, that we may conceivably someday be able to manipulate the brain to affect how someone deals with numbers." In order to examine the thought processes of volunteers, the researchers monitored electrical activity in a region of the brain called the intraparietal sulcus. This part of the brain is known to be important in attention and hand motion. Previous studies have hinted that some nerve-cell clusters in this area are also involved in numerosity, the mathematical equivalent of literacy.
The scientists used a method called intracranial recording, which allowed them to monitor brain activity while people were immersed in real-life situations. The researchers tapped into the brains of three volunteers who were being evaluated for possible surgical treatment of their recurring, drug-resistant epileptic seizures; this involved removing a portion of the patient's skull and positioning packets of electrodes against the exposed brain surface. (more)