Airline passengers don’t seem to think of security as a superhuman task – that extra step on the way to their gates is more of a bother than anything else. What fliers don’t realize, though, is that scanning a confusing background for any of a nearly infinite variety of threats, like security screeners do, actually pushes the limits of human perception.
From University of Illinois at Urbana-Champaign :
Checkpoints get a checkup
X-ray vision isn’t the only thing airport security screeners have going for them
Airline passengers don’t seem to think of security as a superhuman task – that extra step on the way to their gates is more of a bother than anything else. What fliers don’t realize, though, is that scanning a confusing background for any of a nearly infinite variety of threats, like security screeners do, actually pushes the limits of human perception.
That’s why a team of researchers from the University of Illinois at Urbana-Champaign, in an effort to aid training, recently investigated the cognitive processes used by security personnel. The study was conducted by Jason McCarley, Arthur Kramer, Christopher Wickens, Eric Vidoni, and Walter Boot of the University’s Beckman Institute and appears in the May issue of Psychological Science, a journal of the American Psychological Society.
The researchers asked subjects to pretend they were airport security screeners, looking for knives in colored X-ray images of bags. The subjects had to scan the images and decide whether each one was safe, while an eye tracker recorded their gaze. They looked at four sets of bags with similar knives in them before the researchers gave them a fifth set of images with different knives.
Over the first four sets of bags, the subjects learned to search faster and more accurately. When the knives changed, though, subjects’ searching abilities dropped significantly. They were still better than when they started, but it’s apparent that when the search target changed, the task became harder. This happened even though subjects were warned to expect new targets.
The key to screening, then, is familiarity with the target items, not the procedure. Instead of studying scanning techniques, screeners should hone their skills by practicing with every variety of gun, knife and nail file they might encounter.
