The New York Times writes:

The theory is that it’s distracting to hold a phone and drive with just one hand. But a large body of research now shows that a hands-free phone poses no less danger than a hand-held one — that the problem is not your hands but your brain.

“It’s not that your hands aren’t on the wheel,” said David Strayer, director of the Applied Cognition Laboratory at the University of Utah and a leading researcher on cellphone safety. “It’s that your mind is not on the road.”

From: A Problem of the Brain, Not the Hands: Group Urges Phone Ban for Drivers

I think the question people want answered before they stop using phones in their cars is, “What is it about talking on a phone – even using a hands-free kit – that impairs my driving ability?”

I have my guesses, but I thought this reason from the same article sounded quite reasonable:

It may be that talking on the phone generates mental images that conflict with the spatial processing needed for safe driving. Eye-tracking studies show that while drivers continually look side to side, cellphone users tend to stare straight ahead.

Whatever your personal thoughts on the matter are, you should definitely ask yourself: Do you ever feel an absence of quickness or awareness while driving when you’re also talking on the phone?