Door to Door: The Magnificent, Maddening, Mysterious World of Transportation by Edward Humes Page B

whether driving or cookingor dancing. In most endeavors, this is a harmless belief; but when traveling 65 miles per hour, the stakes are too high to be governed by myth. We’re not talking about walking and chewing gum here, but about tasks that require thought and attention. The truth is, no matter how it feels or appears subjectively, the human brain cannot pay attention to two cognitive tasks at the same time. Computers can do this but not humans. We are not built for it.
    What the brain is really good at is toggling between mind-absorbing tasks—shifting focus rather than dividing it, then picking up where it left off when it toggles back. So when drivers are messing with cell phones or car stereos or dropped baby bottles, they are not driving. They have toggled, shifting focus and attention from one task to another, sometimes quite rapidly, but never simultaneously.
    This is the essence of distraction and it’s not limited to staring down at a phone instead of out through the windshield. Brain scans of drivers talking on the phone while staring straight ahead show that activity in the area of the brain that processes moving images decreases by one third or more—hard evidence of a distracted brain. There have been many fatal crashes attributed to this “inattention blindness,” commonly called “tunnel vision.” Drivers talking on cell phones or performing other non-driving tasks can become so focused on the non-driving activity that their brains fail to perceive half the information their eyeballs are receiving from the driving environment. They can appear to be paying attention—the drivers may even think they are paying attention—but they are distracted drivers. This is not a matter of skill or practice or experience. It’s biology.
    The U.S. Department of Transportation made a public service video a few years ago featuring a fatal crash in Grand Rapids, Michigan, that illustrates this problem. 13 A twenty-year-oldwoman, while driving on a city street, spoke by cell phone with someone at the church where she did volunteer work with elementary school–aged children. Witnesses later told police that she was looking straight ahead out the windshield while talking on her phone—not looking down, not texting, not dialing. Yet she drove right through a red light at an intersection into cross traffic. The light had been changed long enough for several cars to move through the intersection right in her field of view, yet she kept going, never braking but speeding into the intersection against the light, where she broadsided another car at 48 miles an hour. A twelve-year-old boy in the car she broadsided was killed in the collision.
    The problem isn’t that humans can’t be good drivers. When focused and fully engaged, humans can be fantastic drivers, capable of displaying the same sort of innate mental calculation of trajectories and safe passage as a star football quarterback and his receiver use to complete a pass forty yards downfield. At the same time, the brain is very good at ignoring false signs of danger—thereby avoiding the constant traffic slowdowns that would result from stopping for every possible hazard—and able to distinguish a person running into traffic from a wayward balloon blowing into the road without a moment’s hesitation. That might sound like a no-brainer, but that balloon would give fits to the literal computer brain of a driverless car, which would likely grind to a halt for the balloon as quickly as for a person.
    The problem is that staying focused and fully engaged for sustained periods of time is not what humans do best, with or without a cell phone in hand. Driving can be boring, the conditions monotonous, or the street or intersection so familiar that we hardly notice or think about it. That’s when the brain’s ability to stay focused on safe driving decays, because humans are terrible at doing repetitive,