According to the National Highway Traffic Safety Administration, inattentive driving is responsible for at least a quarter of all crashes. The use of cell phones, including dialing, texting and talking, has been an ongoing safety concern. A study that will be reported in an upcoming issue of the Brain Research Journal further confirms the safety hazards associated with driving and cell phone use. The study, which was conducted by scientists at Carnegie Mellon University, shows that just listening to a cell phone while driving can reduce by 37 percent the amount of brain activity associated with driving. The study was conducted by volunteers using driving simulators and MRI brain scanners. “Driving while listening” significantly increased the likelihood of drivers weaving out of their lanes which is a major cause of vehicle crashes. The study showed that making calls on hands-free devices does not sufficiently eliminate distractions.
“Drivers need to keep not only their hands on the wheel, they also have to keep their brains on the road,” said neuroscientist Marcel Just, director of the Center for Cognitive Brain Imaging. Because driving and listening draw on two different brain networks, scientists had previously suspected that it might be possible for the networks to work independently on each task. But the new study demonstrates that there is only so much the brain can do at one time, no matter how different two tasks are.
“The clear implication is that engaging in a conversation could jeopardize judgment and reaction time if an atypical or unusual driving situation arose,” Just said. “Heavy traffic is no place for an involved personal or business discussion.”

Source: Carnegie Mellon University