Just Shut Up, Will You

摘要

Many countries have made it illegal to natter into a hand-held mobile phone while driving. But the latest research provides further confirmation that the danger lies less in what a motorist's hands do when he takes a call than in what the conversation does to his brain. Even using a "hands-free" device can impair a driver's attention to an alarming extent.rnMelina Kunar of the University of Warwick, in England, and Todd Horowitz of the Harvard Medical School ran a series of experiments in which two groups of volunteers had to pay attention and respond to a series of moving tasks on a computer screen that were reckoned equivalent inrndifficulty to driving. One group was left un-distracted while the other had to engage in a conversation about their hobbies and interests using a speakerphone. As Dr Kunar and Dr Horowitz report in Psychonomic Bulletin & Review, those who were making the equivalent of a hands-free call had an average reaction time 212 milliseconds slower than those who were not. That, they calculate, would add 5.7 metres (18 feet) to the braking distance of a car travelling at lookph (62mph). The researchers also found that the group using the hands-free kit made 83% more errors in their tasks than those who were not talking.