Info Overload

Never saw the stop sign? Vanderbilt University researchers say a bottleneck occurs in the brain area that processes visual information, a limitation that can lead to everything from traffic accidents to football turnovers.

Psychologist René Marois says that within a visual scene, most people can reliably recall only four items once the scene is gone from view. “People have the impression that the brain is like a computer,” says Marois. “But in reality we have severe capacity limits.”

Because our eyes provide such a richly subjective experience of the world, we tend to overestimate how much of a scene we are actually processing, like the harried quarterback who overlooks an intercepting defender—or your unwitting dash through the intersection. When it comes to the visual world, says Marois, “we definitely know less than we think we know.”