Distracted: The Multitasking Myth

Mention distracted driving and most folks automatically think of talking on a hand-held cell phone or texting as the major culprits that take a driver's mind off the task at hand operating the vehicle safely.

And while texting or talking on a hand-held phone are the most prevalent forms of driver distractions in this instant communication age, they aren't the only ways for drivers to wind up out of control and in trouble when their mind wanders. April is Distracted Driving Awareness month and the National Safety Council is urging all drivers especially those who make their living on the road to be alert to the dangers of multitasking while operating a vehicle and offers information to help drivers better understand the distracted brain to avoid risky behavior on the road. While truckers are already banned from using anything but hands-free phones while driving, the NSC warns that even legal use of hands-free devices can be very dangerous. In a white paper released in 2012 titled "Understanding the Distracted Brain: Why Driving While Using Hands-Free Cell Phones Is Risky Behavior," NSC notes that hands-free devices often are seen as a solution to the risks of driver distraction because they help eliminate two obvious risks visual, looking away from the road and manual, removing your hands off of the steering wheel. However, using a hands-free phone doesn't eliminate the third type of distraction: the cognitive distraction from listening and responding to a disembodied voice that can significantly impair your driving ability. And while you may think you are successfully multitasking when driving and carrying on a phone conversation, the truth is you are not doing either task driving or conversing with optimal focus or effectiveness. Multitasking is a myth, NSC explains. In order to comprehend this it's important to understand how the brain works.

Human brains do not perform two tasks at the same time. Instead, the brain handles tasks sequentially, switching between one task and another. Brains can juggle tasks very rapidly, which leads us to erroneously believe we are doing two tasks at the same time. In reality, the brain is switching attention between tasks performing only one task at a time, NSC notes. When people attempt to perform two cognitively complex tasks such as driving and talking on a phone, the brain shifts its focus and people develop "inattention blindness" where important information falls out of view and is not processed by the brain, NSC says. Vision is the most important sense we use for safe driving, yet drivers using hands-free cell phones have a tendency to "look at" but not "see" objects. Estimates indicate drivers using cell phones look at but fail to see up to 50% of the information in their driving environment, NSC notes. Brain researchers have also identified "reaction-time switching costs," which is a measurable time when the brain is switching its attention and focus from one task to another. Research studying the impact of talking on cell phones while driving has identified that slowed reaction time to potential hazards are "tangible, measurable and risky," NSC warns. A University of Utah driving simulator study found drivers using cell phones had slower reaction times than drivers impaired by alcohol at a .08 blood alcohol concentration, the legal intoxication limit. Braking time also was delayed for drivers talking on hands-free and hand-held phones. For every information input, the brain must make many decisions: whether to act on information processed, how to act, execute the action and stop the action. While this process may take only a fraction of a second, all of these steps do take time. When driving, fractions of seconds can be the time between a crash or no crash, injury or no injury, life or death, NSC says. Under most driving conditions, experienced drivers are performing well-practiced, automatic driving tasks such as slowing for a yellow or red light, staying within a lane, noting the speed limit and navigation signs, and checking rear- and side-view mirrors. People can do these driving tasks safely with an average cognitive workload, NSC notes, and during the vast majority of road trips, nothing bad happens. But that also can lead drivers to feel a false sense of security and lead them to believe they can safely multitask. However, when the expected occurs, the driver's ability to react will be impaired. NCS has compiled more than 30 research studies and reports by scientists around the world to compare driver performance with handheld and hands-free phones. All of these studies show hands-free phones offer no safety benefit over hand-held devices when driving, NCS notes. A Carnegie Mellon University study produced MRI pictures of the brain while study participants drove on a simulator and listened to spoken sentences they were asked to judge as true or false. Researchers found that listening to sentences on cell phones decreased activity in the brain's parietal lobe by 37%, an area associated with driving in other words, listening and language comprehension drew cognitive resources away from task of driving. The same study also found decreased activity in the area of the brain that processes visual information, the occipital lobe. While listening to sentences on cell phones, drivers had more problems, such as weaving out of their lane and hitting guardrails. This task did not require holding or dialing the phone, and yet driving performance deteriorated. The scientists concluded this study demonstrates there is only so much the brain can do at one time, no matter how different the two tasks are, even if the tasks draw on different areas and neural networks of the brain. NSC's research seems to show that truck drivers may be at even greater risk of not recognizing their susceptibility to distracted driving. "Even when people are aware of the risks, they tend to believe they are more skilled than other drivers, and many still engage in driving behaviors they know are potentially dangerous." NSC says. To further educate drivers on the dangers of multitasking while driving, the National Safety Council is sponsoring a free webinar on April 10, "What were you thinking? The myth of multitasking." To register for the webinar go to http://eventcallregistration.com/reg/index.jsp?cid=36015t11 The Great Multitasking Lie Infographic (Courtesy of the National Safety Council) http://www.nsc.org/safetyroad/DistractedDriving/Pages/The-Great-Multitasking-Lie.aspx

More reading: http://www.nsc.org/safetyroad/DistractedDriving/Pages/DDAM.aspx>