Perception psychologists come to the aid of airport security screeners

Jeremy Wolfe, a professor of ophthalmology at Harvard Medical School who runs the Vision Attention Lab at Brigham and Women’s Hospital, argues that security screeners at airports might do a better job spotting weapons if they spent their downtime playing video games — specifically, wasting aliens in violent first-person shooters such as Halo 3. This is one of the tentative findings emerging from psychologists trying boost the human ability to find threatening objects in X-rayed luggage. This once-esoteric subfield has bloomed in recent years, giving rise to competing theories and rival labs. The Boston Globes’s Christopher Shea writes that baggage screening might seem on the surface like a repetitive and uncomplicated job, but it turns out to be very hard. Even well-trained security officers have trouble spotting guns, knives, and plastic explosives amongs the thousands of hair dryers, socks, MP3 players, metal toys, and the occasional cured ham that flows by during a typical week. A government report issued last week noted that agents were able to sneak fake bombs past security at nineteen airports by creating minor distractions, including carrying a roll of coins to set off a metal detector. A Transportation Security Administration (TSA) document revealed that when investigators placed simulated explosives into bags at Los Angeles International Airport last year, human screeners missed three-quarters of them. Researchers note that any new and improved solutions to security screening would have applications beyond transportation safety: In medicine, for example, radiologists have to find tumors in thousands of mammograms and other X-rays, and have a high failure rate. This is where psychologists come in: They find that the human mind fails at such tasks in very specific ways — and that understanding and compensating for those failures can help as much as new technology.

“The screener folks often get a bum press,” says Wolfe. His Vision Attention Lab has received $100,000-$150,000 annually from DHS over the last five years. “But I have seen very little evidence that they are anything other than professionals trying to do a very good job. And the people who are designing the task aren’t stupid either — but it’s really hard,” he says. One reason it is hard is that the human brain has trouble with rare events. In 2005 Wolfe and two colleagues made news with a paper in the prestigious journal Nature that identified a “prevalence effect” in security screening. No