Lance Oliver © AMA American Motorcyclist Association 2002
‘Inattentional blindness’ studies shed light on car-motorcycle accidents
Your headlight’s on. You’re wearing a brightly colored helmet and clothing. The driver of the oncoming car looks right in your direction. And then he turns left into your path anyway.
Later, he tells the police officer: “I never saw the motorcycle.”
How could that be? Just ask all the people who didn’t see the woman in the gorilla suit.

Allow us to explain.
Recent scientific studies focusing on a phenomenon known as “inattentional blindness” may help us understand why car drivers often end up causing accidents with motorcycles they “didn’t see.”
One particularly interesting study was conducted by Daniel Simons and Christopher Chabris at Harvard University.

In it, subjects watched a video of two teams of three people—one team in white shirts, the other wearing black—passing an ordinary basketball among themselves. Some subjects were told to count the number of passes by either the white or black team (the “easy task”). Others were told to keep separate mental counts of bounce passes and aerial passes (the “hard task”).
During the video, a woman carrying an umbrella walks through the scene.
In another version, a woman in a full gorilla suit walks through. In a third video, the gorilla stops in the middle of the scene, thumps its chest, and walks off.
Here’s the scary part: Forty-six percent of the subjects did not see the umbrella woman or the gorilla in the first two versions. In the third version, 50 percent didn’t notice the gorilla.
Basically, people concentrating on one task do not see something unrelated because they aren’t expecting it, says Simons, an associate professor of psychology at Harvard.
“The intuition people have is that something different like that will jump out at them and they will notice it,” adds Simons. “But their intuition is wrong.”
Simons believes it is not a stretch to apply the same thinking to car drivers encountering motorcycles on the street. In a sea of cars, a motorcycle could be that “something different” the driver does not expect, and therefore does not see.
The key, he says, is attention.
In the Harvard study, called “Gorillas in our Midst,” the subjects engaged in the “hard task” were less likely to notice the umbrella woman or the gorilla than were subjects performing the “easy task.”
The more their attention was focused elsewhere, the less likely they were to notice unexpected occurrences.
Simons notes that some of the subjects in the study did not believe a gorilla actually walked through the scene until they were shown the tape again. They were astounded they missed something that was so obvious on second viewing.
On the surface, the study seems to be bad news for safety-minded motorcyclists. It suggests that no matter what we do, some inattentive drivers will still miss us. And it has obvious implications for those concerned with the whole subject of driver distractions, including cellphone use.
Meanwhile, a study by researchers at Sussex University in England found that experienced drivers were actually less likely than inexperienced drivers to look for potential hazards in unexpected locations. The study, which analyzed eye movements of drivers watching video clips of traffic situations, appears to indicate that years of driving train someone to look for the expected, not what is actually there
But there are useful lessons for all of us that can be gleaned from these “inattentional blindness” studies.
For instance, although being conspicuous is no guarantee you’ll be seen, Simons reports that it may improve your odds on the road.
He cites other studies in which subjects were watching black-and-white objects on a screen and an unexpected red object appeared. Even with the color contrast, about 30 percent did not see the red object. But at least the other 70 percent did.
Simons plans to join the faculty at the University of Illinois next year and hopes to do further research more directly related to traffic safety by using the university’s driving simulator.
But on the basis of the results so far, Simons suggests that while nothing can guarantee you’ll be seen by car drivers, such attention-getting equipment as modulating headlights (legal in most states), along with brightly colored clothing and helmets, may help.
“The goal” he says, “would be to make things more distinctive.”
Remember, though, that just because the driver is looking right at you, that doesn’t mean he or she really sees you. After all, half the people never saw the gorilla.
© 2001 by the American Motorcyclist Association