The National Transportation and Safety Board (NTSB) has called for a nationwide ban on the use of cell phones and text message devices while driving.
Carnegie Mellon University's Marcel Just, a leading neuroscientist who has studied how using cell phones impairs driving ability, applauds NTSB's proposal.
"Banning the use of cell phones by drivers in non-emergency situations could be another dramatic step forward in further reducing the unacceptably high levels of driving-related fatalities in the U.S., which is most recently at about 33,000 people killed annually," Just said.
"While recent improvements in automobile safety equipment have made an enormous contribution, it remains to make improvements in the most important factor, driver performance, and to save thousands of additional lives per year. We are our own worst enemy."
Just's research shows that simply listening to someone speak on the other end of a cell phone reduces by 37 percent the amount of brain activity associated with driving, compared to driving alone.
To determine this, Just used functional magnetic resonance imaging (fMRI) to study participants in a driving simulator.
When they were listening to a sentence, they were more likely to weave in their lane than when they were driving undisturbed. The decrease in available brain resources can cause drivers to commit the same type of driving errors that can occur under the influence of alcohol.
Another study from Just's laboratory showed that subjects could not willfully ignore someone speaking to them; the processing of a spoken message was so automatic that it could not be gated out, and continued to affect the brain activation associated with a second concurrent task.
This study shows the dangers of cell phone use by drivers cannot be overcome by strategically controlling one's attention.
Just's research shows that making cell phones hands-free or voice-activated is not sufficient in eliminating distraction to drivers.
"Drivers need to keep not only their hands on the wheel; they also have to keep their brains on the road," Just said.
"The clear implication of our work is that engaging in a conversation could jeopardize the judgment and reaction time if an atypical or unusual driving situation arose. Driving in quick-moving traffic is no place for an involved phone discussion, let alone texting."
Marcel Just is the D.O. Hebb Professor of Psychology at Carnegie Mellon University and director of the Center for Cognitive Brain Imaging.