October 20, 2009, 4:03 PM — Cell phone use while driving has been in the news lately. The NY Times recently reported about safety research from the National Highway Traffic Safety Administration. The NHTSA concluded that cell phone use and driving don’t mix well, but these conclusions were never released to the public. Many states are discussing whether to pass legislation banning cell phone use while driving. Other states and officials dismiss the dangers inherent in driving and talking on the phone.
Is talking on a cell phone while driving dangerous? Here are some figures:
• Drivers using phones are four times more likely to cause a crash than other drivers.
• The likelihood that they will crash is the same as someone driving with .08% blood alcohol level (the point where drivers are usually considered drunk drivers).
• A 2003 Harvard study estimated that cell phone distractions caused 2,600 traffic deaths, and 330,000 accidents that result in moderate or severe injuries.
• Cell phone use has increased. From 1995 to 2008, the number of wireless subscribers in the US increased 8 times, to 270 million and the minutes talked increased 58 fold.
• The NHTSA estimated that at any time during the daytime in 2007, 11% - or 1.8 million drivers- were using a cell phone.
Past remedies to reduce the dangers of driving and talking on a cell phone have focused on using hands-free devices to reduce the risk. However the NHTSA study and fundamental brain science tell us that the real risk is not in our hands, it's in our minds.
What makes cell phone use while driving so dangerous?
Driving is one of the most cognitively complex activities. To drive safely, we have to concentrate, observe and process information quickly and correctly. We have to respond to all sorts of information that is constantly bombarding us from all directions as we drive. We have to be able to estimate speed and distance quickly and correctly.
Driving really requires 100% of our attention. When we speak on the cell phone while we are driving, we may think we are multi tasking. In fact, our brains do not really “multi task”. Our attention is divided between activities, and our brain switches quickly from one activity to the other.
The danger of talking on a cell phone while driving lies in the fact that the brain can’t process separate streams of information efficiently. Furthermore, it is “hard-wired” to prioritize attention to the cell phone conversation. Since words spoken during a cell phone conversation “disappear” once they are spoken, the brain must attend closely to the audio information to be sure it captures the conversation. The visual view of the road or highway does not change as rapidly as the audio information, so the brain periodically ignores some of the visual information. Also, when people are talking on the phone, they are not just talking; they are seeing all kinds of images in their mind. This visualization may be harmless most of the time, but it can be a real tragedy when a pedestrian steps into traffic or a car swerves into another lane. When we are talking on the phone, the brain lacks the processing power to react quickly enough to these changing situations.
Conversely, driving and talking to a passenger in the car is not dangerous because adult riders help keep the driver alert and can also point out dangerous conditions, and are quieter in heavy traffic or hazardous weather.
So which cognitive skills are most affected by cell phone use?
Attention, visual scanning, information processing and decision making are the most affected cognitive skills. When you think about driving, you realize how much you need these cognitive skills, and how risky it could be to reduce the effectiveness of any of these functions when you’re driving.
The bottom line is that talking on the cell phone while driving is dangerous. Safe driving is not just about keeping our eyes on the road and our hands on the wheel; it’s about focusing our brains on one of the most cognitively-challenging activities we routinely perform.
For more information on how the brain works turn to the CogniFit blog.