It happened last Sunday at football stadiums around the country. Suddenly, 50,000 individuals became a single unit, almost a single mind, focused intently on what was happening on the field—that particular touchdown grab or dive into the end zone. Somehow, virtually simultaneously, each of those 50,000 people tuned into what the other 49,999 were looking at.
Becoming part of a crowd can be exhilarating or terrifying: The same mechanisms that make people fans can just as easily make them fanatics. And throughout human history we have constructed institutions that provide that dangerous, enthralling thrill. The Coliseum that hosts my local Oakland Raiders is, after all, just a modern knockoff of the massive theater that housed Roman crowds cheering their favorite gladiators 2,000 years ago.
(For Oakland fans, like my family, it’s particularly clear that participating in the Raider Nation is responsible for much of the games’ appeal—it certainly isn’t the generally pathetic football.)
In fact, recent studies suggest that our sensitivity to crowds is built into our perceptual system and operates in a remarkably swift and automatic way. In a 2012 paper in the Proceedings of the National Academy of Sciences, A.C. Gallup, then at Princeton University, and colleagues looked at the crowds that gather in shopping centers and train stations.
In one study, a few ringers simply joined the crowd and stared up at a spot in the sky for 60 seconds. Then the researchers recorded and analyzed the movements of the people around them. The scientists found that within seconds hundreds of people coordinated their attention in a highly systematic way. People consistently stopped to look toward exactly the same spot as the ringers.
The number of ringers ranged from one to 15. People turn out to be very sensitive to how many other people are looking at something, as well as to where they look. Individuals were much more likely to follow the gaze of several people than just a few, so there was a cascade of looking as more people joined in.
In a new study in Psychological Science, Timothy Sweeny at the University of Denver and David Whitney at the University of California, Berkeley, looked at the mechanisms that let us follow a crowd in this way. They showed people a set of four faces, each looking in a slightly different direction. Then the researchers asked people to indicate where the whole group was looking (the observers had to swivel the eyes on a face on a computer screen to match the direction of the group).
We follow a crowd via perceptual mechanisms that are quick almost beyond belief. Getty Images
Because we combine head and eye direction in calculating a gaze, the participants couldn’t tell where each face was looking by tracking either the eyes or the head alone; they had to combine the two. The subjects saw the faces for less than a quarter of a second. That’s much too short a time to look at each face individually, one by one.
It sounds impossibly hard. If you try the experiment, you can barely be sure of what you saw at all. But in fact, people were amazingly accurate. Somehow, in that split-second, they put all the faces together and worked out the average direction where the whole group was looking.
In other studies, Dr. Whitney has shown that people can swiftly calculate how happy or sad a crowd is in much the same way.
Other social animals have dedicated brain mechanisms for coordinating their action—that’s what’s behind the graceful rhythms of a flock of birds or a school of fish. It may be hard to think of the eccentric, gothic pirates of Oakland’s Raider Nation in the same way. A fan I know says that going to a game is like being plunged into an unusually friendly and cooperative postapocalyptic dystopia—a marijuana-mellowed Mad Max.
But our brains seem built to forge a flock out of even such unlikely materials.