Close Encounters of the Rude Kind

One of my personal crotchets is people who walk down busy city sidewalks without looking where they’re going. These days they might be texting on an electronic device, but it’s not the technology I object to. They could just as well be reading a book. What’s annoying is the expectation that the crowds will part, that all the other pedestrians will make the effort to get out of their way.

This may be simple rudeness. But I suspect that some of these people truly believe they can skillfully multi-task even in a crowd. Well they can’t, and I’ve now got science to prove it. Finnish researchers did a laboratory simulation to see how pedestrians avoid collisions in everyday sidewalk encounters. Millions of people pass by millions of other people without incident every day on the world’s streets, and the scientists wanted to know how we manage this. Although they simulated polite pedestrians, their findings hold a valuable lesson for the self-centered as well.

Cognitive psychologist Lauri Nummenmaa and her colleagues studied volunteers’ eye gaze as they encountered an animated man walking toward them on a city street. They wanted to see if the simulated stranger’s eye gaze was an important cue in avoiding sidewalk collisions. In the simulation, the stranger looked steadily either to the left or the right, and the volunteers had to decide which way to move. The results, reported on-line this week in the journal Psychological Science, were clear: If the stranger looked to his left, volunteers not only looked but also moved to the stranger’s right; and vice versa. The scientists also ran a more realistic scenario in which the stranger looked straight ahead until the last minute, and then suddenly shifted his gaze left or right. They got the same results.

Much recent work on the brain’s “mirror neurons” suggests that humans automatically mimic others, and that this unconscious aping is important to social interaction. Interestingly, the volunteers in these studies did not mirror the stranger’s eye gaze, suggesting that their own eye movements are not simply an automatic neuronal reflex. That reflex may be occurring, but it doesn’t stop there: It appears the pedestrians are also “mind reading,” quickly but deliberately interpreting a stranger’s eye gaze as a signal of intent to walk left or right. That is, they are social animals, analyzing and navigating a social world.

This lab simulation captures only half a real-life sidewalk encounter. On an actual city street, not only am I observing and reasoning about your gaze and intentions, you are doing the same with my gaze. It’s a social contract that protects both of us and keeps the world moving smoothly. Unless, of course, your mind is somewhere else.

For more insights into the quirks of human nature, visit the “Full Frontal Psychology” blog at True/Slant. Excerpts from “We’re Only Human” appear regularly in Newsweek.com and in the magazine Scientific American Mind.