University of Utah Professor David Strayer teamed up with AAA to find out what distracts us the most when we're behind the wheel.
When David Strayer's children were younger, on family trips they would sometimes make faces at passing drivers. One time, as he was explaining to them that it wasn’t a good idea to distract a driver, Strayer realized that the other driver hadn’t even noticed. “The person was on a cell phone,” says Strayer, a professor of cognition and neural science at the University of Utah. “He was not paying attention to what anyone else was doing—he was completely zoned out.”
This has become the state of driving in America, where at any given time an estimated one in 10 drivers is talking on the phone—the highest rate in the world. You’ve seen it: the driver who weaves from side to side, who inexplicably slows, or who seems mildly surprised that the traffic light has turned green.
Few people have devoted as much time and intellectual energy to the problem of distracted driving as Strayer has. His latest research, conducted for the AAA Foundation for Traffic Safety, takes a novel approach. Drivers were fitted with electrode caps to record brain activity, and researchers measured their reaction times and hazard-detection accuracy both in a driving simulator and on the road.
After analyzing the data, Strayer created a 5-point scale to categorize how much certain tasks distract drivers. Driving itself requires a base level of mental effort. “It’s category one, not category zero,” says Jake Nelson, AAA director of traffic safety advocacy and research.
But what happens when you layer other activities on top of that? Do hands-free phones impair drivers less than handheld ones? Is listening to the radio the same as listening to an email read by a smartphone app? Strayer’s findings may surprise you.
- Phone conversations had much the same effect whether the driver used a handheld or hands-free device (2.45 versus 2.27 on the 5-point scale).
- Listening to an audiobook required more attention (1.75) than listening to the radio (1.21).
- Speech-to-text email and messaging systems were much more demanding—a “category three” distraction.
- The top level of distraction (5.0) was recorded when drivers worked on complex math and memory exercises.
What in the real world of driving is even remotely similar to these exercises? Strayer wondered the same thing. Then he recalled a new car he test-drove that included a system for buying movie tickets.
“You’re not sure what’s playing, what times are available, what theaters,” he says. “You reserve your seat, give your credit card info—that entire series of operations is going to be at least a category three, and it wouldn’t surprise me if some of those pushed into category four.”
All of this is happening while your eyes are on the road and your hands are on the wheel. But because of the phenomenon known as “inattention blindness,” or the ability to miss something right in front of you, you can still be distracted even when you seem to be paying attention. “Eyes off the road is a bad thing,” Strayer says. “It’s just that eyes on the road doesn’t mean it’s safe.”
The increasing availability and complexity of in-car, voice-activated technologies prompted AAA to support Strayer’s work. Nelson says these findings don’t warrant a call to ban voice-activated technology across the board, nor are they meant to be punitive to automakers. “We simply want to say, hey, we’ve learned something new here that we want to sit down and talk about,” he says.
To learn more about traffic safety and see the details of Strayer’s study, visit AAA.com/distraction.
This article was first published in July 2013. Some facts my have aged gracelessly. Please call ahead to verify information.