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One reason may have been that they were not looking in the right places. Researchers have long known that inexperienced drivers have much different “visual search” patterns than more experienced drivers. They tend to look overwhelmingly near the front of the car and at the edge markings of the road. They tend not to look at the external mirrors very often, even while doing things like changing lanes. Knowing where to look—and remembering what you have seen—is a hallmark of experience and expertise. In the same way that eye-tracking studies have shown reliable differences in the way artists look at paintings versus the way nonartists do (the latter tend to zero in on things like faces, while artists scan the whole picture), researchers studying driver behavior can usually tell by a driver’s glance activity how experienced they are.

Teenage drivers were, in many ways, the perfect next step for DriveCam. Like the drivers of commercial vehicles, teens are often driving someone else’s car, and they are driving under the supervision of a higher authority—in this case, Mom and Dad. A trial in Iowa put DriveCams in the cars of twenty-five high school students for eighteen weeks. Triggered events were sent to parents, and the scores (using an anonymous ID) were posted so the drivers could judge exactly where they stood in relation to their peers. According to Daniel McGehee, the trial’s head and director of the Human Factors and Vehicle Safety Research Program at the University of Iowa’s Public Policy Center, teenagers in Iowa, because of its agricultural character, can begin driving to school at fourteen. “That crash rate is absolutely out of sight,” he said. Teenagers in Iowa also drive a lot: In thirteen months of driving, the twenty-five drivers put over 360,000 miles on the odometer, many of them on the statistically most dangerous roads: rural two-lane highways.

The early clips he showed were indeed troubling: drivers sailing heedlessly through red lights, or singing and looking around absentmindedly before flying off a curve into a cornfield. Admittedly, I felt a bit uneasy peering into this little cocoon of privacy during these moments of raw, unfiltered emotion. Apparently the teens, in this age of reality television, were not so shy. The DriveCam contains a button that drivers can press to add a comment about a triggered event. Some teens used it to record diary entries, a sort of dashboard confessional about events in their lives outside the car. Driving also provided a rather unique window on to the social lives of teens, McGehee told me. “We could tell when someone got a new girlfriend or boyfriend. They would drive more aggressively to show off.”

But it was the safety effects, not the video confessions or dating habits, that interested the researchers. When I spoke to McGehee later, he was in the sixteenth week of the trial. “The riskiest drivers dropped their safety-relevant behaviors by seventy-six percent,” he said. “The farther we get into this, the risky behaviors are just drying up.” Whereas before, the riskiest drivers had been triggering the device up to ten times a day, McGehee said, they were now triggering it only once or twice a week. “Even the magnitude of those triggers is pretty benign relative to their early days,” he noted. “They still might be taking a corner a little too fast but it might be right above the threshold.”

What was really happening to the teens? Were they afraid of getting in trouble with their parents? Were they just seeing their own mistakes for the first time? Or were they simply gaming the system, trying to crack the code like they do with their SATs? “I think what you see is that drivers in this pure behavioral psychology loop are becoming sensors themselves,” McGehee said. “This little accelerometer in there—they start to sense over time what the limit is.” As DriveCam’s Weiss put it, “One kid said, ‘I figured out how to beat the system. I just look way ahead and anticipate traffic and slow down for corners, and I haven’t set it off in a month.’” He was, whether he realized it or not, acting like a good driver.

But what happens when the DriveCam is gone? “I don’t pretend to represent DriveCam as anything but an extrinsic motivation system,” Moeller had said. He admits that in the early days of a DriveCam trial, the mere presence of the camera is enough to get drivers to act more cautiously, in a version of the famous “Hawthorne effect,” which says that people in an experiment change their behavior simply because they know they are in an experiment. But without any follow-up coaching, without “closing the feedback loop,” results begin to erode. “The driver starts to think, ‘The camera’s not intrusive at all. Nothing’s ever going to happen—this is just there so in case I get in a crash this will record who was at fault,’” Moeller said. “When you inject coaching in, then he realizes there is an immediate and certain consequence for his risky driving behavior. That twenty-second loss of privacy is enough for most people.”

The things that DriveCam finds itself coaching drivers on most often do not involve actual driving skills per se—like cornering ability or obstacle avoidance—but mistakes that are born from overconfidence. The most striking example of this came in a trial that Weiss, then with the Mayo Clinic in Minnesota, did with an ambulance company that was trying to improve the “ride experience” for patients. One might think the DriveCam would have been triggered quite regularly in emergency situations, when the drivers, with lights and sirens, were speeding their patients to the hospital, careening around corners, and slaloming through red lights. That was not the case. “It’s actually smoother when you have the red lights and siren on, is how it turned out,” Weiss explained. “We triggered more events—we had harder cornering and more erratic driving—when they were just doing their own thing.” Weiss, himself a former ambulance driver and paramedic, suspected he knew why. “The big difference between running lights and a siren and your normal driving is that you’re focused. They’re seeing the hazards that are out there and they’re slowing sooner when someone can’t see them. Smoother is quicker when you’re running lights and a siren.”

Since most of us don’t have sirens and lights, our driving is of the everyday variety. As the sense of routine begins to take over, we begin to ratchet up our sense of the possible—how close we can follow, how fast we can take curves—and become conditioned to each new plateau. We forget those things that the Stanford researchers were learning as they tried to teach their robot to drive: It is not as easy as it appears. Lisk, who had that morning reviewed a sheaf of collision reports, said that “the large majority were just people who didn’t have enough space, or were not attentive enough. A lack of good old-fashioned basic driving skills was a huge part of it.”

He showed one clip, of a driver moving rather quickly down an open lane toward a tollbooth, flanked on either side by queues of cars. “The driver’s thinking it’s wide open. It’s a football mentality—I’ve got all my blockers and I can go,” Lisk said. It’s as if the driver has already imagined himself to have passed through the lines of cars and past the open tollbooth. There is just one problem: All those other drivers are eagerly salivating over that same space. “Because they’re boxed in they’ve got to come in a pretty abrupt angle and at low speed,” Lisk said. “We see a lot of collisions where the driver hasn’t slowed down enough when they’re approaching that high-risk, open-lane situation.”

This may help explain why EZ Pass–style automated payment lanes at tollbooths, which should theoretically help reduce crashes at these statistically risky areas—drivers no longer have to fumble for change—have been shown to increase crash rates. Drivers approach at a higher speed, with nothing to stop them from zooming through the toll plaza, while other cars, finding themselves in the “wrong” lanes, dart out and jockey among lanes more than they would have under the old system, in which there was less chance of finding a shorter queue.

Each month, DriveCam receives more than fifty thousand of these triggered clips, making it, Moeller said, the world’s largest “repository of risky driving behavior.” The technology of the camera is allowing glimpses into what has been, for most of the automobile’s existence, a kind of closed world: the inner life of the driver.

“Driver behavior” has previously been teased out through things like driving simulators, test tracks, or actually having a researcher sit in the car, clipboard in hand—none of which is quite like real-world driving. Cars could be watched from the outside, via cameras or lab assistants on highway overpasses, but that did not give any glimpse into what the driver was doing. The study of crashes was based largely on police investigations and witness reports, which are both prone to distortion—the latter particularly so.

People are more likely to assign blame to one person or another when a crash is severe, research has shown, than when it is minor. In another study, a group of people were shown films of car crashes. When the subjects were asked, a week later, to gauge the speed of various cars in the films, they estimated higher speeds when the questions used the word “smash,” versus words like “hit” or “contacted.” More subjects remembered seeing broken glass when the word “smash” was used, even though no glass was broken. A driver’s own memory of events is usually clouded by a desire to lessen their own responsibility for an event (perhaps so as to not conflict with their enhanced self-image or to avoid legal liability). “Baker’s law,” named after crash reconstructionist J. Stannard Baker, notes that drivers “tend to explain their traffic accidents by reporting circumstances of lowest culpability compatible with credibility”—that is, the most believable story they can get away with.

Most elusive of all, before Drivecam-style devices, were the crashes that
almost
happened. There was no way to determine why and how they nearly occurred (or did not), nor how often these near misses took place. If the top of the triangle was murky, the bottom of the triangle was as vast a mystery as the deepest ocean floor.

That has now changed, and large-scale studies, using technology like DriveCam’s, are providing new clues into how drivers behave and, most important, new insight into just why we encounter trouble on the road. The answer is not so much all the things that the road signs warn us about—the high winds on bridges or the deer crossing the highway. Nor is it mostly tire blowouts, faulty brakes, or the mechanical flaws that prompt car makers to issue recalls (“human factors” are said to account for 90 percent of all crashes). Nor does it seem to be “driver proficiency” or our ability to understand traffic signals.

What seems to gives us the most trouble, apart from our overconfidence and lack of feedback in driving, are the two areas in which Stanley and Junior, Stanford’s clumsy robot drivers, have a decided edge. The first is the way we sense and perceive things. As amazing as this process is, we do not always interpret things correctly. More important, we aren’t always aware of this fact. The second thing that separates us from Stanley and Junior on the road is that we are not driving machines: We cannot keep up a constant level of vigilance. Once we feel we have things under control, we begin to act differently. We look out the window or talk on a cell phone. Much of our trouble, as I will show in the next chapter, comes because of our perceptual limitations, and because we cannot pay attention.

How Our Eyes and Minds Betray Us on the Road

Any man who can drive safely while kissing a pretty girl is simply not giving the kiss the attention it deserves.

—Albert Einstein

Here is a common traffic experience: You are driving, perhaps down a mostly empty highway, perhaps on the quiet streets around your house, when you suddenly find yourself “awake at the wheel.” You realize, with a mixture of wonder and horror, that you cannot remember what you have been doing for the past few moments—nor do you know how long you have been “out.” You may find yourself sitting in your driveway and asking, as the Talking Heads once did, “How did I get here?”

This phenomenon has been called everything from “highway hypnosis” to the “time-gap experience,” and while it has long puzzled people who study driving, it is still not fully understood. What is known is that it usually happens in fairly monotonous or familiar driving situations. Some scientists suggest that it’s related to drowsiness, and that we may even be taking what are called “microsleeps” at the wheel.

What is also unclear is how much attention we were actually paying to the road while under the spell of highway hypnosis versus to what extent we have simply forgotten everything that happened during that period. You may have wondered why you did not drift off the side of the road. Perhaps you were lucky; one study that had subjects drive for several (boring) hours in a driving simulator found that the roughly one in five drivers who succumbed to “driving without awareness”—as measured by EEG readings and eye movements—drifted out of their lane one-third of the time. You may have wondered what would have happened if a car (or bike or small child) had veered into the lane while you were zoning out. Would you have responded in time?
Did
a near accident almost happen during that period, one that you have since forgotten about?

Think back to the blank stares of drivers monitored by DriveCam. Why is it so hard to pay attention while we are driving? How and why do our eyes and mind betray us on the road?

Driving, for most of us, is what psychologists call an “overlearned” activity. It is something we’re so well practiced at that we’re able to do it without much conscious thought. That makes our life easier, and it is how we become good at things. Think of an expert tennis player. A serve is a complex maneuver with many different components, but the better we become at it, the less we think of each individual step. This example comes from Barry Kantowitz, a psychologist and “human factors” expert at the University of Michigan; he has spent years studying the safest and most efficient ways for humans to interact with machines, working with everyone from NASA pilots to operators of nuclear power plants. “One of the interesting things about learning and attention is that once something becomes automated, it gets executed in a rapid string of events,” he says. “If you try to pay attention, you screw it up.” This is why, for example, the best hitters in baseball do not necessarily make the best hitting coaches. Coaches need to be able to explain what to do; Charley Lau, the legendary batting coach and author of the classic book
The Art of Hitting .300,
never actually hit .300 himself.

The more overlearned an activity becomes, the less cognitive workload it imposes—though studies suggest that even the most mundane activities, like switching gears, never become fully automatic. The task always costs something. Having less workload is, on the one hand, a good thing. If, while driving, we were to really process every potential hazard, carefully analyze every motion and decision, and break down each maneuver into its component parts, we would quickly become overwhelmed. People who bring test subjects into driving simulators find something like this happening. “We’re not going to get a driver to be one hundred percent vigilant to the driving task, because we would all get out of the car sweating,” according to Jeffrey Muttart, a crash investigator and researcher at the University of Massachusetts. “If you see people get out of a driving simulator test, almost the first thing they do is take a deep, cleansing breath. Because I’m frying their brains. This is a ten-minute drive, and they want to try hard to do well.”

Too little workload has its own problems. We get bored. We get tired. We lapse into highway hypnosis. We may make errors. Anyone who has (like me) put on mismatched socks or run the coffeemaker without adding coffee or water will be aware of this phenomenon. The absolute ease of the activity allows the mind to wander. A classic psychological principle, the Yerkes-Dodson law, posits that the ability to learn is harmed by too little—or too much—“arousal.” This idea applies as well to human performance. Driving in North Dakota is on the low side of the curve, driving in Delhi on the high side. The ideal conditions presumably lie somewhere in between.

But where? Most driving rarely requires our full workload. So we listen to the radio, look out the window, or, increasingly, talk on the cell phone or read text messages—in the case of one fatal crash in California, the driver may have been operating a laptop computer as he drove. Or we may change the way we drive—we speed up because driving does not seem overly taxing. To the extent that this keeps us in the middle of the Yerkes-Dodson curve, it’s a good thing. But the problem with driving is that we never know for sure when things are going to change very quickly, when that nice empty road—seemingly safe for a cell phone conversation—is going to turn into an obstacle course. We may also be unaware of just how much workload our secondary activity is consuming.

“Let’s say you’re driving on a straight road. It’s relatively easy. I could ask you to do arithmetic at the same time and it wouldn’t mess up your driving,” Kantowitz said. “If you’re driving on a curved road, especially if it’s sharp curve, that takes more attention if you’re to keep the car operating safely within the lane. If I ask you to do mental arithmetic on a curve you’ll do it more slowly and you’ll screw it up. Or if you do it well you’ll screw up the driving.” A study by a Danish researcher found that those same types of arithmetic problems took longer to do when driving in a village than on a highway.

This raises another point: Researchers look at how driving is affected when people do other things, but research also shows that secondary tasks suffer as well. We become worse drivers
and
worse talkers. This is obvious to anyone who has listened to the wandering, interrupted musings of a driver talking on a phone (journalists know that people calling from their cars give terrible interviews). As Kantowitz put it, “There’s no free lunch.”

“My basic belief after almost forty years of studying this stuff is that people can’t time-share at all,” Kantowitz told me. “You only get the appearance. It’s like speed-reading. You think you can read really fast but your comprehension disappears. You can give the illusion of time-sharing if it’s simple information, but in general we’re not built for time-sharing.” Think of the annoying crawl type found on the bottom of the screen on CNN and other news networks. We are led to believe that this is how people now process information, as if we are suddenly genetically programmed to multitask. Studies have shown, however, that the more information there is on the screen, the less we actually remember.

The relative ease of most driving lures us into thinking we can get away with doing other things. Indeed, those other things, like listening to the radio, can help when driving itself is threatening to cause fatigue. But we buy into the myth of multitasking with little actual knowledge of how much we can really add in or, as with the television news, how much we are missing. As the inner life of the driver begins to come into focus, it is becoming clear not only that distraction is the single biggest problem on the road but that we have little concept of just how distracted we are.

In the largest study to date of the way we actually drive today, the Virginia Tech Transportation Institute, working with NHTSA, equipped one hundred cars in the Washington, D.C., and northern Virginia area with cameras, GPS units, and other monitoring devices, and then set about recording a year’s worth of what it calls “pre-crash, naturalistic driving data.” After poring over forty-three thousand hours of data and more than two million miles of driving, the study found that almost 80 percent of crashes and 65 percent of the near crashes involved drivers who were not paying attention to traffic for up to three seconds before the event.

That period of time is critical. “A total time of two seconds looking away from the forward roadway is when people start to get in trouble,” explained Sheila “Charlie” Klauer, a researcher at VTTI and the study’s project manager. “That’s when they get to the point when they are starting to lose track of what’s going on in front of them.” The two-second window is not technically related to the “two-second rule” for following distance, but the comparison is instructive. The point is that a lot can happen in two seconds—like colliding with the car in front if it came to a stop or slowed—but drivers, lulled by the expectancy that it will not stop, drive as if the world will not have changed when they return their eyes to the road after that two seconds. They drive as if the world is a television show viewed on TiVo that can be paused in real time—one can duck out for a moment, grab a beer from the fridge, and come back to right where they left off without missing a beat. For many of the crashes, Klauer found that “the eye glance happened to be at exactly the wrong time. If they had not chosen to look away at that very second they would have probably been okay.”

The sources of distraction inside a car have been painstakingly logged by researchers. We know that the average driver adjusts their radio 7.4 times per hour of driving, that their attention is diverted 8.1 times per hour by infants, and that they search for something—sunglasses, breath mints, change for the toll—10.8 times per hour. Research has further revealed just how many times we glance off the road to do these things and how long each glance takes: In general, the average driver looks away from the road for .06 seconds every 3.4 seconds. “On average, radio tuning takes seven glances plus or minus three,” said Linda Angell, a safety researcher at General Motors, in a conference room at the Technical Center in Warren, Michigan. “That’s for an oldish radio. We do better with the modern radio, which zeroes you in on the right region.” Most of these glances, Angell noted, do not take our eyes off the road for longer than 1.5 seconds. But there are exceptions, such as “intense displays”(e.g., lots of features) or looking for a button you have not pressed in a while. The iPod is changing the equation yet again: Studies have shown that scrolling for a particular song takes our eyes off the road for 10 percent longer than simply pausing or skipping a song—plenty of time for something to go wrong.

Even a succession of very short glances, less than two seconds each, can cause problems. Researchers talk of the “fifteen-second rule,” which indicates the maximum amount of time a driver should spend operating any kind of in-car device, whether navigation or radio, even as they are (at least occasionally) looking at the road. “What we believe is that task time is very important,” Klauer said. “The longer the task time, the more dangerous the task is, and the greater the crash risk.” And so a fifteen-second task might require only short glances at the device, but, Klauer said, “that risk increases every time the driver looks away.”

The study found that while dialing a cell phone put drivers at a greater crash risk, talking on a cell phone presented only a slightly higher risk than normal driving. “When a driver is talking or listening on their cell phone, at any given moment within that conversation what our odds ratio is telling us is they’re only at a slightly higher crash risk than an alert driver. Statistically speaking, it’s not different,” Klauer said. Does that mean talking on a cell phone is safe? Maybe it’s all that
dialing
we need to worry about. But the study also found that talking (or listening) on a cell phone was a contributing factor in as many crashes as dialing was. “We think that’s probably true because while dialing is a much more dangerous task while the driver’s doing it, the task is fairly short,” Klauer told me. “But drivers typically talk on their cell phone for a long period of time. Over that long period of time a lot more crashes and near crashes are more apt to occur. That slight increase in crash risk is starting to add up.” As more drivers talk for longer periods, Klauer said, “it’s going to become a lot more dangerous.”

The reason we talk for a long time on our cell phones is related to the reason we all think we are better drivers than we are, and to the thing that also makes us think we are better drivers on our cell phones than we are: lack of feedback. Cell phone users are not aware of the risk because, by all surface measures, they seem to be driving fine. Traffic affords us these illusions—until it does not, as the hundred-car study showed. “Cell phone conversations are particularly insidious because you don’t notice your bad performance, particularly the cognitive side,” John Lee argues. “So if you’re dialing the phone, you get immediate feedback because you don’t quite stay in the lane, because you’re punching the buttons.” Once the dialing is done, the driver can again look at the road. The weaving stops. They seem to be in control.