Cognitive scientists don't often get a chance to save lives. This summer James Staszewski will continue to do so.

The U.S. Army originally approached Staszewski, a cognitive psychology professor at Carnegie Mellon University, eight years ago to troubleshoot the training program for personnel who would be detecting land mines in war and peacekeeping zones. Trainees had fared abysmally in exercises, catching only 10 to 20 percent of mock mines. Staszewski had been researching how people acquire exceptional memory and calculation skills. His studies upheld the idea that expertise accrues from experience, so in principle good minesweeping should be teachable. The army paired Staszewski with Vietnam War veteran Floyd “Rocky” Rockwell, who was working with a humanitarian group removing mines in war-torn countries.

Staszewski videotaped Rockwell and a protg as they swept for dud mines on a training ground at Fort AP Hill, Va. Their detector was essentially a long stick with a magnet on the end that clicks when metal is near. Staszewski recorded the positions of the detector heads, the clicks and the men's voices as they thought out loud. Army instructions recommended sweeping the head above the ground at three feet per second, but the two experts went much slower, a foot per second, floating the detector in overlapping sweeps. Crucially, they did not just listen to clicks; they built up images in their heads of a suspected object's contours, “prospecting for familiar spatial patterns,” Staszewski says.

Staszewski subsequently developed a training system to inculcate these techniques. Combat engineers who spent an extra 12 to 15 hours practicing the new method found simulated mines 85 to 95 percent of the time and detected 97 to 100 percent of defused mines. Staszewski later created a similar method for an experimental army mine detector equipped with radar. Using a more precise camera system to observe accomplished sweepers, he is currently trying to identify small differences that allow the experts to discriminate between mines and debris.