On the face of it, math has a whole lot to do with the way we physically see the world. Whether it is adding up the number of people in front of us in a supermarket line or checking the numbers on a receipt, many of the day-to-day math applications and concepts we deal with revolve around vision.
Or do they? A new project carried out by Johns Hopkins University neuroscientists suggests that vision is not as tightly wrapped up with math as we might think.
As part of the study, researchers demonstrated the brain network responsible for numerical reasoning is identical in both blind and sighted people.
“There is a perception that blind people specifically struggle with math, because it’s a very visual-spatial thing,” lead author Shipra Kanjlia, a graduate student in the university’s Department of Psychological and Brain Sciences, told Digital Trends. “What this study shows is that the ability to do math is present in everyone, blind or not.”
In the experiment described in the paper, both congenitally blind people and sighted people wearing blindfolds were asked to solve math equations while undergoing a brain scan. Participants were given increasingly complex spoken equations and told to answer them. In both blind and sighted participants, the part of the brain used for numerical reasoning — the intraparietal sulcus — responded as the math puzzles were considered.
Even more intriguingly, however, the study revealed the brain’s visual cortex showed large amounts of activity as blind people did the math questions, with greater levels of activity shown for more complex equations. This part of the brain — used for processing vision in a sighted person — did not show any activity when sighted participants answered the questions.
“This suggests that different areas of the brain can be repurposed,” Kanjlia said. “For example, if someone undergoes a stroke, they may lose some part of the brain, but that doesn’t mean that another part of the brain can’t pick up the slack. The message I take away from this paper is that the brain is amazingly flexible, but also surprisingly resilient. Developmentally it changes when you don’t think it would, and doesn’t change when you think it should change.”