Bad drivers take note: researchers from Toronto’s York University say they’ve pinpointed part of the brain that could be to blame.
People can generally keep track of three or four different things—whether it’s another moving car, a traffic light or pedestrian—without keeping their eyes glued on them. “You don’t remember all the details, but you’ve got this general sketch,” says Dr. Doug Crawford, Canada Research Chair in Visual-Motor Neuroscience and lead author of the study. Called the “visual map,” this helps us navigate our environment and keep track of our surroundings. But these landmarks can easily be disrupted, new research shows.
In the study, to be published this month in The Journal of Neuroscience, the team of researchers temporarily interfered with subjects’ visual maps by using a magnetic pulse on the brain’s parietal cortex (while the pulse has no longterm effects, it “scrambles things up a bit,” Crawford says). After introducing the pulse, “It’s as if we took away the memory of where those things were,” he explains. When this brain function is reduced, people might think they’re observing a complete scene—when in fact they’re missing some vital pieces of information.
Crawford says he’s “betting there’s all kinds of people” who are affected by this, and could be endangering themselves or others as a result. “At a driver’s test, you never get tested on how well you remember that kind of information,” he says. The parietal cortex, he notes, can be damaged in stroke patients, and anything from alcohol to the flu might impact its function. As of right now, “it’s an unknown,” he says.
With Canada’s population getting older, age could be another factor that influences this important part of the brain. Senior drivers already account for the second-largest proportion of road deaths, after teenagers and young adults. And within the next 25 years, it’s predicted, one in four Canadian drivers will be a senior citizen.
“Considering how much driving we do and what a dangerous activity it is, this whole topic deserves a lot more study,” Crawford says.