BOB HIRSHON (host):
The risks of hands-free phones. I’m Bob Hirshon and this is Science Update.
Several studies have found that hands-free cell phones affect drivers just as much as hand-held models. A recent experiment may explain why. Harvard Medical School psychologist Todd Horowitz and his colleagues found that normal hands-free phone conversations impaired visual attention. But listening to a novel over the phone, or simply repeating the caller’s words, had no effect.
TODD HOROWITZ (Harvard University):
It’s not listening. It’s not moving your mouth and making sounds and making words. It’s that intervening bit, where you have to actually think about what you’re going to say and generate some new content for whoever you’re talking to.
Of course, this also happens in conversations with passengers. But Horowitz notes that those people can at least see what’s happening on the road, and tend to clam up when the driver needs to concentrate. I’m Bob Hirshon for AAAS, the Science Society.