Although words and language are typically processed in the human brain's left hemisphere and the right is usually responsible for numerical reasoning, a new study from researchers at the University of Jena has pinpointed a part of the brain important for the visual processing of numbers, and it's active in both hemispheres.
The region, called the "visual number form area" (NFA), was visualized using high-resolution magnetic resonance recordings that observed levels of activity in this region, which is normally difficult to access, in healthy test subjects.
During the study, the researchers presented subjects with numbers, letters and pictures of everyday objects, all the while recording their brain activity using magnetic resonance imaging (MRI). Using this process, they were able to identify the NFA, which is located in a small area at the underside of the left and right temporal lobes, by the high level of activity in the region observed during the presentation of numbers in comparison to letters and other images.
"This region has been a kind of blind spot in the human brain until now," Mareike Grotheer, coauthor of the study, said in a press release, which is due to the fact that it is hidden by bone, air and the acoustic meatus, meaning previous MRI scans had difficulty picking it up.
In order to get a better look, the scientists used a high-performance 3 Tesla MRI scanner, allowing them to capture three-dimensional images of the subjects' brains at a high spatial resolution in order to eliminate white noise and avoid picking up other surrounding structures.
The findings were published in the Jan. 6 issue of The Journal of Neuroscience.
