Talking on a cell phone while driving can lead to fatal accidents. Lawmakers in many states are considering making it illegal to use a cell phone while driving unless you have a hands-free phone.

But as this ScienCentral News video reports, hands-free phones may not be safer after all.

Hands-Free Isn’t Risk-Free

Surely if you’re not holding a phone in your hand while driving, you’re more able to react to a potential driving emergency. But studies are revealing that there’s really no difference between using hands-free phones and hand-held phones while driving.

David Strayer, a psychologist from the University of Utah, says, “We’ve done a couple of studies that have directly compared hand-held to hands-free cell phones. We didn’t find any difference. When people are talking on the cell phone, their reactions are slowed by about 20 percent.” It turns out that the problem isn’t in the driver’s hands; it’s in his head.

Strayer used a $100,000 driving simulator and an eye-tracking device to measure how many billboards, road signs, and objects drivers looked at as they drove. Half the drivers also talked to someone using a hands-free cell phone. Later, he showed the drivers pictures of billboards and signs, and asked them if they remembered seeing them. The drivers who talked on phones remembered half as many of the objects they looked at compared to those who were driving without talking on phones. So even though the eye-tracker showed that they looked right at certain signs, the cell phone drivers did not remember seeing them.

Strayer calls this phenomenon “inattention blindness,” and explains that “even though the driver who is using the cell phone is looking out the windshield, they’re not necessarily seeing what’s out there because their mind is directed elsewhere.” So these conversations, whether hand-held or hands-free, impair a driver’s performance by withdrawing attention from the scene, which can cause anything from slower reaction time to traffic signals, to dangerous accidents.

Inattention blindness from cell phones is the beginning of what Strayer calls a “new class of distractions” for our modern multitasking culture. “You now have navigation systems, electronic mail, you can send and receive faxes, you can surf the Internet while you’re driving. There’s all of a sudden a new class of technology that’s making its way into the vehicle that has a much greater potential for distraction.”

Virtual Reality

Strayer’s study also indicated that the drivers did not even realize that they weren’t really “seeing” everything in front of them on the road. They thought they were driving perfectly safely, and figured that if anyone had a problem driving while using a cell phone, it would be “the other guy.” He explains, “Part of this inattention blindness shuts down their own processing and their own assessment of how well they’re driving. So they themselves are not as aware of their driving performance while they’re using a cell phone.”

So what comes over these cell phone users as they drive? Strayer thinks they enter a kind of “virtual reality” with the person they’re chatting with. “Neither you nor the other person is really dealing with the physical environment that you’re in. Instead you’re in this kind of cell phone-induced virtual reality, and you interact in that virtual environment rather than talk about the physical here and now of driving.”

This certainly doesn’t describe any “other guy” you’d want to be sharing the road with. The data seems to suggest that restricting hand-held phones and allowing hands-free phones is not likely to eliminate cell phone-related accidents.

The study was published in the March 2003 issue of the Journal of Experimental Psychology: Applied. A portion of the study also is featured in the February-March issue of Injury Insights, published by the National Safety Council. The University of Utah funded the work.