Magazine advertisers know they have just three seconds to reel you in. That'sthe average length of time a reader looks at an ad before flipping the page. Now the battle for your bucks is taking a high-tech turn, thanks to a device originally developed to detect neurological problems.
The instrument, called the Vision 2000, can reveal which ads--and which parts of them--best attract readers. While a tiny head-mounted video-camera records everything within a person's field of view, the device measures his or her eye position 120 times each second. The resulting videotape--which includes a dancing dot of light representing the exact location of a viewer's gaze--tells marketers which words and images readers lingered over and which they ignored.
In clinics and hospitals, eye-tracking machines have a more noble purpose: diagnosing brain and eye injuries. For example, some dizzy spells stem from a psychological problem, while others are caused by damage to a brain region that helps us keep our balance. But only brain-injured individuals have trouble moving their eyes in time with a computer image--a symptom the machine readily detects, says Moshe Eizenman, Ph.D., professor of biomedical engineering at the University of Toronto.
