Info Overload

Seeing less than meets the eye. Within a visual scene, most people can reliably recall only four items once the scene is gone from view.

By Erik Strand, published on July 1, 2004 - last reviewed on August 18, 2005

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.”