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A Hard Landing

NASA research scientist Richard Haines spent much of his career at Ames Research Center, a space and aeronautics think tank in northern California. He is best known publicly for his attempts to document UFO experiences. But in the late 1970s and early 1980s, he and his colleagues Edith Fischer and Toni Price conducted a pioneering study on pilots and information display technologies using a flight simulator.³¹ Their experiment is important because it is one of the most dramatic demonstrations of looking without seeing. They tested commercial airline pilots who were rated to fly the Boeing 727, one of the most common planes of the time. Commercial airline pilots tend to be among the most experienced and expert pilots—many flew in the military for years, and only the top pilots get to fly the larger commercial planes, where they have responsibility for hundreds of passengers on every flight. The subjects in this study were either first officers or captains who had flown 727s commercially for over one thousand hours.

During the experiment, the pilots underwent extensive training on the use of a “head-up display.” This technology, which was relatively new at the time, displayed much of the critical instrumentation needed to fly and land the simulated 727—altitude, bearing, speed, fuel status, and so on—in video form directly on the windshield in front of the pilots, rather than below or around it as in an ordinary cockpit. Over the course of multiple sessions, the pilots flew a number of simulated landings under a wide range of weather conditions, either with or without the head-up display. Once they were practiced with the simulator, Haines inserted a surprise into one of the landing trials. As the pilots broke through the cloud ceiling and the runway came into view, they prepared for landing as they had on all of the previous trials, monitoring their instruments and the weather conditions to decide whether or not to abort. In this case, however, some of them never saw the large jet on the ground turning onto the runway right in front of them.

Such “runway incursions”—which happen when planes enter runways when they shouldn’t—are among the more common causes of airplane accidents. More than half of the incursions result from pilot error—a pilot taxis into the path of another aircraft. Just as the USS Greeneville was exceptionally unlikely to surface into another ship, most runway incursions present little or no risk of a collision. In fiscal year 2007, the Federal Aviation Administration recorded a total of 370 runway incursions at American airports. In only 24 of them was there a significant potential for a collision, and only 8 of those involved commercial flights. Over the four years from 2004 through 2007, there were a total of 1,353 runway incursions in the United States, 112 of which were classified as serious, and only 1 of which resulted in a collision. That said, the single worst accident in aviation history involved a runway incursion. In 1977, in the Canary Islands, KLM flight 4805 took off down the runway and collided at full speed with Pan Am flight 1736, which was taxiing in the other direction on the same runway. The collision of these two Boeing 747s resulted in 583 deaths.

Although runway incursions are relatively common compared with other aviation accidents, airplane collisions of every sort are exceptionally rare. With only eight runway incursions out of more than 25 million flights in 2007, you would need to take an average of one commercial round-trip flight every day for about three thousand years to have a more than even chance of encountering a serious runway incursion. These incidents are relatively common, with the key word being “relatively.” They are still exceedingly rare—and consequently, they are unexpected.³²

What’s surprising about Haines’s flight simulator experiment is that the head-up display should—or at least our intuition suggests that it should—have kept the pilots’ attention on the place where the parked plane was going to appear. They never had to look away from the runway to see their instruments. But two of the pilots using the head-up display would have plowed right through the plane on the runway had the experimenter not aborted the trial. The plane was clearly visible just seconds after the pilots cleared the clouds, and they had about seven more seconds to safely abort their landing. The pilots using the head-up display were also slower to respond, and when they tried to execute a “missed approach” (by pulling up to go around and make a new landing attempt), they were late in doing so. The two who didn’t manage to abort their landings in time were both rated either good or excellent in their simulator flying performance. When the trial was over, Haines asked them whether they saw anything, and both said no. After the experiment, Haines showed the pilots a videotape of the landing with the airplane stationed in their path, and both expressed surprise and concern that they had missed something so obvious. One said, “If I didn’t see [the tape], I wouldn’t believe it. I honestly didn’t see anything on that runway.”³³ The plane on the runway was their invisible gorilla—they didn’t expect it to be there, so they never saw it.

Now that we understand that looking is not seeing, we can see that the intuition that a head-up display will enhance our ability to detect unexpected events is wrong. Head-up displays can help in some respects: Pilots get faster access to relevant information from their instruments and need to spend less time searching for that information. In fact, flight performance can be somewhat better with a well-designed head-up display than without one. Using a so-called conformational display, which superimposes a graphical indication of the runway on top of the physical runway visible through the windshield, pilots can fly more precisely.³⁴ Although the head-up display helps pilots perform the task they are trying to accomplish (like landing a plane), it doesn’t help them see what they are not expecting to see, and it might even impair their ability to notice important events in the world around them.

How is it possible that spending more time with the world in view actually reduces our ability to see what is right in front of us? The answer, it seems, stems from our mistaken beliefs about how attention works. Although the plane on the runway was right in front of the pilots, fully in view, the pilots were focusing their attention on the task of landing the plane and not on the possibility of objects on the runway. Unless pilots inspect the runway to see if there are any obstructions, they are unlikely to see something unexpected, such as a plane taxiing onto their landing strip. Air traffic controllers are, after all, supposed to control the traffic to make sure that this doesn’t happen. If a failure to inspect the runway were the only factor in play, though, a head-up display would be no worse than looking away at your instruments and then back to the windshield. After all, in both cases, you could spend the same amount of time ignoring the runway. You either focus attention on the readings on the windshield or focus attention on the instruments surrounding the windshield. But as Haines’s study showed, pilots are slower to notice unexpected events when they are using a head-up display. The problem has to do not as much with the limits on attention—which are in effect regardless of whether the readings are displayed on the windshield or around it—as with our mistaken beliefs about attention.

Hold All Calls, Please

Imagine that you are driving home from work, thinking about what you will do when you get there and everything you left unfinished at the office. Just as you begin to make a left turn across a lane of oncoming traffic, a boy chases a ball into the road in front of you. Would you notice him? Maybe not, you should now be thinking. What if, rather than being lost in thought while you were driving, you were talking on a cell phone? Would you notice then? Most people believe that as long as their eyes are on the road and their hands are on the wheel, they will see and react appropriately to any contingency. Yet extensive research has documented the dangers of driving while talking on a phone. Both experimental and epidemiological studies show that the driving impairments caused by talking on a cell phone are comparable to the effects of driving while legally intoxicated.³⁵ When talking on a cell phone, drivers react more slowly to stoplights, take longer to initiate evasive maneuvers, and suffer from generally reduced awareness of their surroundings. In most cases, neither drunk driving nor driving while talking on a cell phone lead to accidents. In part, that is because most driving is predictable and lawful, and even if you aren’t driving perfectly, the other drivers are trying not to hit you. The situations in which such impairments are catastrophic, though, are those that require an emergency reaction to an unexpected event. A slight delay in braking might make the difference between stopping short of the boy in the street and running him over.

For the most part, people are at least familiar with the dangers of talking on a cell phone while driving. We’ve all seen distracted drivers run a stop sign, obliviously veer into another lane, or drive at 30 mph in a 45 mph zone. As columnist Ellen Goodman wrote, “The very same people who use cell phones…are convinced that they should be taken out of the hands of (other) idiots who use them.”³⁶

The realization that (other) people are unable to drive safely while talking on the phone led to a movement to regulate the use of handheld cell phones while driving. New York was one of the first states to pass such legislation. The law banned the use of handheld phones while driving, based on the intuition that taking our hands off the wheel to use the phone is the main danger posed by talking while driving. In fact, the New York legislation provided for tickets to be waived if drivers could prove that they subsequently purchased a hands-free headset. Not surprisingly, the telecommunications industry supported the New York bill and regularly promotes the safety and advantages of hands-free headsets. A flier from AT&T Wireless proclaims, “If you use your wireless phone while driving, you can keep both hands on the wheel,” and a similar brochure from Nokia ranks using a hands-free device whenever possible as second on their list of ten safety recommendations. In our survey, 77 percent of Americans agreed with the statement, “While driving, it’s safer to talk on a hands-free phone than a handheld phone.” The assumption underlying these beliefs and claims as well as most laws on distracted driving—that as long as you are looking at the road, you will notice unexpected events—is precisely the illusion of attention. Given what you now know about the gorilla experiment, you can probably guess what we will say next.

The problem isn’t with our eyes or our hands. We can drive just fine with one hand on the wheel, and we can look at the road while holding a phone. Indeed, the acts of holding a phone and turning a steering wheel place little demand on our cognitive capacities. These motor-control processes are almost entirely automatic and unconscious; as an experienced driver, you don’t have to think about how to move your arms to make the car turn left or to keep the phone up to your ear. The problem is not with limitations on motor control, but with limitations on attentional resources and awareness. In fact, there are few if any differences between the distracting effects of handheld phones and hands-free phones. Both distract in the same way, and to the same extent.³⁷ Driving a car and having a conversation on a cell phone, despite being well-practiced and seemingly effortless tasks, both draw upon the mind’s limited stock of attention resources. They require multitasking, and despite what you may have heard or may think, the more attention-demanding tasks your brain does, the worse it does each one.

In a second part of our original gorilla experiment, we tested the limits of attention by making the task of the subjects (counting basketball passes) more difficult. Rather than just a single count of the total number of passes made by the white team, we asked people to keep two separate mental counts, one of aerial passes and one of bounce passes (but still focusing on the white team). As we predicted, this increased by 20 percent the number of people missing an unexpected event.³⁸ Making the counting task harder requires people to devote more attention to it, leaving fewer mental resources available to see the gorilla. As we use more of our limited attention, we are that much less likely to notice the unexpected. The problem is with consuming a limited cognitive resource, not with holding the phone. And most important, as the incredulous reactions of our study participants demonstrate, most of us are utterly unaware of this limit on our awareness. Experiment after experiment has shown no benefit whatsoever for hands-free phones over handheld ones. In fact, legislation banning the use of handheld phones might even have the ironic effect of making people more confident that they can safely use a hands-free phone while driving.

One could argue that our gorilla experiment isn’t really comparable to the scenario of driving while talking on a cell phone. That is, increasing the difficulty of the counting task as we did might increase the burden on attention more than a cell phone conversation would. There’s an easy way to account for this possibility, though: Do an experiment! To explore the effects of cell phone conversations on inattention directly, Brian Scholl and his students at Yale used a variant of the “red gorilla” computerized task described earlier and compared a group who performed the task as usual with one that performed it while simultaneously carrying on a cell phone conversation.³⁹ In their particular variant of the task, about 30 percent of the participants missed the unexpected object when they were just doing the tracking task. However, participants who performed the task while talking on a phone missed the unexpected object 90 percent of the time! Simply having a conversation on a phone tripled the chances that they would fail to see something unexpected.

This sobering finding shows that cell phone conversations dramatically impair visual perception and awareness. These impairments are due to the limits of attention and not due to the nature of the phone; even though both tasks seem effortless, both demand our attention. Intriguingly, the cell phone conversation didn’t impair the subjects’ ability to do the tracking task—it just decreased their chances of noticing something unexpected. This finding may explain why people falsely think that cell phones have no effect on their driving: People are lulled into thinking that they drive just fine because they can still perform the primary task (staying on the road) properly. The problem is that they’re much less likely to notice rare, unexpected, potentially catastrophic events, and our daily experience gives us little feedback about such events.

If you’re like many people who have heard us speak about inattention, cell phones, and driving, you may wonder why talking to someone on a phone should be any more dangerous than talking to the person in the passenger seat, which doesn’t seem objectionable. (Or, if you have responded enthusiastically to our arguments—and thank you for doing so—you may be getting ready for a campaign to make “driving while talking” illegal, no matter whom you are talking to.) It may come as a surprise, then, to learn that talking to a passenger in your car is not nearly as disruptive as talking on a cell phone. In fact, most of the evidence suggests that talking to a passenger has little or no effect on driving ability.⁴⁰

Talking to a passenger could be less problematic for several reasons. First, it’s simply easier to hear and understand someone right next to you than someone on a phone, so you don’t need to exert as much effort just to keep up with the conversation. Second, the person sitting next to you provides another set of eyes—a passenger might notice something unexpected on the road and alert you, a service your cell-phone conversation partner can’t provide. The most interesting reason for this difference between cell-phone conversation partners and passengers has to do with the social demands of conversations. When you converse with the other people in your car, they are aware of the environment you are in. Consequently, if you enter a challenging driving situation and stop speaking, your passengers will quickly deduce the reason for your silence. There’s no social demand for you to keep speaking because the driving context adjusts the expectations of everyone in the car about social interaction. When talking on a cell phone, though, you feel a strong social demand to continue the conversation despite difficult driving conditions because your conversation partner has no reason to expect you to suddenly stop and start speaking. These three factors, in combination, help to explain why talking on a cell phone is particularly dangerous when driving, more so than many other forms of distraction.

For Whom Does Bell Toil?

All of the examples we have discussed so far show how we can fail to see what is right in front of us: A submarine captain fails to see a fishing vessel, a driver fails to notice a motorcyclist, a pilot fails to see a runway obstruction, and a Boston cop fails to see a beating. Such failures of awareness and the illusion of attention aren’t limited to the visual sense, though. People can experience inattentional deafness as well.⁴¹

In 2008, the Pulitzer Prize for Feature Writing went to Gene Weingarten for his Washington Post cover story describing a social “experiment” he conducted with the help of virtuoso violinist Joshua Bell.⁴² As a four-year-old in Indiana, Bell impressed his parents, both psychologists, by using rubber bands to pluck out songs he had heard. They engaged a series of music teachers and by age seventeen Bell had played Carnegie Hall. He was on his way to repeatedly topping the classical music charts, receiving numerous awards for his performances, and appearing on Sesame Street. The official biography on his website begins with these words: “Joshua Bell has captured the public’s attention like no other classical violinist of his time.”

On a Friday morning at rush hour, Bell took his Stradivarius violin, for which he’d paid more than $3 million, to the L’Enfant Plaza subway stop in Washington, D.C. He set up shop between an entrance and an escalator, opened his violin case to take donations, seeded it with some cash of his own, and began to perform several complex classical pieces. Over the course of his forty-three-minute performance, more than one thousand people passed within a few feet of him, but only seven stopped to listen. And not counting a donation of $20 from a passerby who recognized him, Bell made only $32.17 for his work.

Weingarten’s article bemoaned the lack of appreciation for beauty and art in modern society. Reading it, you can sense the pain and disappointment he must have felt while watching the people go past Bell:

It was all videotaped by a hidden camera. You can play the recording once or 15 times, and it never gets any easier to watch. Try speeding it up, and it becomes one of those herky-jerky World War I-era silent newsreels. The people scurry by in comical little hops and starts, cups of coffee in their hands, cellphones at their ears, ID tags slapping at their bellies, a grim danse macabre to indifference, inertia and the dingy, gray rush of modernity.

Fellow staffers at the Washington Post magazine apparently expected a different result. According to Weingarten’s story, they had been worried that the performance might cause a riot:

In a demographic as sophisticated as Washington, the thinking went, several people would surely recognize Bell. Nervous “what-if” scenarios abounded. As people gathered, what if others stopped just to see what the attraction was? Word would spread through the crowd. Cameras would flash. More people flock to the scene; rush-hour pedestrian traffic backs up; tempers flare; the National Guard is called; tear gas, rubber bullets, etc.

After the stunt was over, Weingarten asked famous conductor Leonard Slatkin, who directs the National Symphony Orchestra, to predict how a professional performer would do as a subway artist. Slatkin was convinced a crowd would gather: “Maybe 75 to 100 will stop and spend some time listening.” During the actual performance, less than one-tenth that number stopped, and the National Guard did not mobilize.

Weingarten, his editors, Slatkin, and perhaps the Pulitzer committee members fell prey to the illusion of attention. Even Bell, when he saw the video of his performance, was “surprised at the number of people who don’t pay attention at all, as if I’m invisible. Because, you know what? I’m makin’ a lot of noise!”⁴³ Now that you’ve read about invisible gorillas, neglected fishing vessels, and unseen motorcycles, you can likely guess one reason why Bell went unrecognized for the great musician he is. People weren’t looking (or listening) for a virtuoso violinist. They were trying to get to work. The one person interviewed for the story who correctly understood the minimal response to Bell was Edna Souza, who shines shoes in the area and finds buskers distracting. She wasn’t surprised that people would rush by without listening: “People walk up the escalator, they look straight ahead. Mind your own business, eyes forward.”

Under the conditions Weingarten established, commuters were already engaged in the distracting task of rushing to get to work, making them unlikely to notice Bell at all, let alone focus enough attention on his playing to distinguish him from a run-of-the-mill street musician. And that is the key. Weingarten’s choice of time and location for the stunt nearly guaranteed that nobody would devote much attention to the quality of Bell’s music. Weingarten is concerned that “if we can’t take the time out of our lives to stay a moment and listen to one of the best musicians on Earth play some of the best music ever written; if the surge of modern life so overpowers us that we are deaf and blind to something like that—then what else are we missing?” Probably a lot, but this stunt provides no evidence for a lack of aesthetic appreciation. A more plausible explanation is that when people are focusing attention (visual and auditory) on one task—getting to work—they are unlikely to notice something unexpected—a brilliant violinist along the way.

If we were designing an experiment to test whether or not Washingtonians are willing to stop and appreciate beauty, we would first pick a time and location where an average street performer would attract an average number of listeners. We would then randomly place either a typical street performer or Joshua Bell there on several different days to see who earned more money. In other words, to show that people don’t appreciate beautiful music, you first have to show that at least some people are listening to it and then show that they reward it no more than they do average music. Weingarten wouldn’t have won a Pulitzer had he stationed Bell next to a jackhammer. Under those conditions, nobody would be surprised by the lack of attention to the musician—the deafening sound would have drowned out the violin. Placing Bell next to a subway station escalator during rush hour had the same effect, but for a different reason. People physically could have heard Bell playing, but because their attention was diverted by their morning commute, they suffered from inattentional deafness.

Other factors worked against Bell as well—he was performing relatively unfamiliar classical pieces rather than music that most commuters would know. If Bell had played The Four Seasons or other better-known classical pieces, he might have done better. By doing so, a far less talented musician could have taken in more money than Bell did. When Dan lived in Boston, he occasionally walked from downtown to the North End to get Italian food. At least half a dozen times, he walked past an accordion player who stationed himself at one end of an enclosed walkway that ran past a highway—a perfect place to attract listeners with time on their hands, walking to restaurants that they’d probably have to wait to get into anyhow. For street artists, like for real estate, location is everything. The accordionist played with gusto, showing an emotional attachment to his instrument and his art. Yet, Dan only ever heard him play one song: the theme from The Godfather. He played it when Dan walked to dinner and when Dan walked back from dinner, every time Dan made that trip. Either he spotted Dan before he was within earshot and instantly started playing the Godfather theme as some odd sort of joke or warning (Dan has yet to wake up with a bloody horse’s head at his feet), or he simply recognized the appeal to his audience of playing what may be the most familiar accordion piece. Our bet is that he did quite well. Had Bell performed on a Saturday afternoon, he likely would have attracted more listeners. Had he played shorter pieces on a subway platform rather than extended pieces next to the exit escalator, he might have attracted more listeners who had to wait for trains. And had he played the theme from The Godfather on his three-hundred-year-old violin, who knows.