When Teen Drivers Multitask, They're Even Worse Than Adults

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Everyone knows that the first rule of driving is never take your eyes off the road.

Teen drivers start off being careful, but they tend to start multitasking after just a few months behind the wheel, according to research published Tuesday in the New England Journal of Medicine.

And while older drivers can handle eating or talking to passengers, which trip up the newbies, dialing a cell phone increased the risk of accidents among young and experienced drivers alike.

This isn't great news, since it's well established that distracted driving is a leading cause of accidents among all drivers.

It makes sense that young drivers will start testing their limits after a few months behind the wheel, according to Bruce Simons-Morton, a behavioral scientist with the National Institutes of Health and a coauthor of the study.

"You increase the difficulty of a task until you make an error," Simons-Morton tells Shots. "It seems like a very natural thing but still it's very dangerous, because good driving ability and safety judgment develops over a very long period of time."

Within six months of getting their licenses, young drivers in this study started texting, eating and adjusting the radio while driving as much as their more experienced counterpart. But it takes thousands of hours of practice to get good at driving, according to Simons-Morton. That disconnect may help explain the high accident rates among teenage drivers.

The researchers compared data from two small studies — one tracked 42 newly licensed young drivers and the other looked at 100 drivers with more experience.

All the participants had sensors and cameras installed in their cars. The researchers used the sensors to track when drivers got into accidents or close calls. The videos were then used to see what the drivers were doing just before the accidents occurred.

Because the researchers wanted to focus on the effects of distracted driving, they ignored crashes caused by drunk driving and ones that were clearly caused by other drivers.

Since the number of people in this study was small, Simons-Morton says the results will have to be verified by other research. A couple of bigger studies already in the works, including one that's tracking over 2,000 drivers, might make things clearer.

But Simons-Morton says this is the first totally objective look at teen driver distraction.

The data also showed that for both teenage drivers and adults, talking on a cell phone didn't cause accidents. But dialing the phone increased the risk of crashing in both groups.

"While you're talking on a phone you can still be looking at the forward roadway," Simons-Morton says. Looking away from the road to text or dial is much riskier, he says.

With that in mind, Simons-Morton says it makes sense to restrict cell phone use in cars. "A lot of teenagers are used to talking on the phone and texting before they learn to drive," he says. "And when they start driving, they bring these things right into the vehicle."