A 2005 study conducted by the Insurance Institute for Highway Safety found that drivers who use cell phones while driving were four times more likely to get involved in an accident. It also concluded that accident risk wasn’t affected by whether the driver was using a hand-held phone or a hands-free phone.
New research from Carnegie Mellon University shows that just listening on a cell phone while driving is enough to distract a driver. In this study, 29 volunteers used a driving simulator while inside an MRI brain scanner. They steered a car along a virtual winding road, driving at a high, fixed rate of speed. They were tested while driving undisturbed, and while driving and trying to decide whether a sentence they heard was true or false. The researchers measured activity in 20,000 brain locations, each about the size of a peppercorn.
After a thorough analysis of the data, the researchers were able to conclude that:
- When the drivers were tested while listening to the sentence to see if it was true or false, they lost 37 percent of the normal activity of their brain’s parietal lobe. This is significant because this area of the brain is the one motorists rely on the most when driving. The parietal lobe assimilates all the information the body receives from the senses, and uses it to determine how near/far perceived objects are. There was also a decrease in the activity of the occipital lobe, which assimilates visual information.
When the drivers were tested while listening, they lost their ability to control the car. They not only were unable to stay in their lane, but they frequently hit objects such as guardrails. These are the kinds of driving errors most closely associated with motorists who drive while under the influence of alcohol.