Researchers found that drivers using cell phones, even hands-free devices, aren't processing peripheral vision well. The scientists studied twenty volunteers who used a driving simulator to experience all sorts of distractions, from cars suddenly swerving to a stoplight changing. In one test, a driver on a phone and one focused solely on the road were shown the same series of billboards. The driver not yakking remembered seeing 50 percent more billboards than the driver on the phone, the study found.
Associate professor David Strayer said this is "inattention blindness," an impairment that slows reaction time by 20 percent and made some drive-and-dial practitioners miss half the red lights they were suddenly presented with in some simulations.
"We found that when people are on the phone, the amount of information they are taking in is significantly reduced," he said of the study, the results of which will be published in the March edition of the American Psychology Association's Journal of Experimental Society: Applied. "People were missing things, like cars swerving in front or sudden lane changes. We had at least three rear-end collisions."
The study is among many investigations into the effects of driving and using a cell phone. Most have shown some impairment. New York is the only state with laws punishing those who drive while talking on a handheld cell phone. Thirty states, though, have legislation pending.
The Utah study differed from others because it didn't study the distractions of dialing or holding a phone. Instead, it tried to focus solely on the distractions of having a conversation, Strayer said.
"Most people's knee-jerk reaction is that the cell phone is held, and there is clearly a distraction involved in that," he said.