Medical scientists strongly endorsed the National Transportation Safety Board's recommendation Tuesday to ban nearly all use of cellphones and other portable electronics by drivers, saying the gizmos are just too distracting for the limited multitasking power of the human brain.
"I wholeheartedly support a ban on personal electronic devices, which provide an unprecedented degree of distraction that's very dangerous," said Dr. Lisandro Irizarry, chairman of the emergency department at the Brooklyn Hospital Center in New York.
"Everyone from teenagers to senior citizens is texting," he said in an email to msnbc.com. "It's very easy to get distracted, especially when driving, and end up in the ER."
The NTSB's recommendation specifically said so-called hands-free devices, like Bluetooth headsets, don't solve the problem and should be part of the ban.
That sounds great to Dr. Marcel Just, director of the Center for Cognitive Brain Imaging at Carnegie Mellon University in Pittsburgh, a neuroscientist who has studied how using cellphones impairs driving ability.
"Use of cellphones while driving — handheld or not — is really a hazard, a threat to public safety," Just told msnbc.com. "It costs lives."
The problem is that people think they're better drivers than they really are, and so they believe they can multi-task behind the wheel.
"When you're driving, it feels kind of automatic, so it feels like you're not doing anything, but it's not true," Just said. "Various parts of your brain are working on scanning the road ahead, maintaining your speed, maintaining your lane — all of those things are being done even when it feels like it's not.
Obviously, we can do two things at the same time," he said. "But the critical point is we can't do them as well at the same time."
Processing a conversation with another person consumes 37 percent of the energy that's normally allocated to driving, Just's research indicates. That's "a very, very large percentage that has serious consequences for safety," he said.
While carrying on a conversation in person with a passenger is distracting, "typically there isn't quite as much a social onus on continuing the conversation," he said.
In other words, a passenger who's in the car with you knows enough to shut up if you encounter a hazard on the road. But "with a person on the other end of a cellphone, they don't know to stop talking if something happens," he said.
While he hasn't quantified the difference, Just said, he's convinced "it's worse with a cellphone."
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