People are inherently bad at watching computers work, and unlikely to get any better, no matter how much training we get, new research with airline pilots shows.
“Our study really does suggest that vigilance is a very difficult task for people,” says Jonathan Schooler, professor of psychological and brain sciences at the University of California, Santa Barbara.
“Extended uninterrupted monitoring can be draining. The antidote to that is interruptions that break up the monotony, but we also found that the interruptions themselves contributed to lapses. And people will spontaneously mind-wander, and that can also contribute to monitoring difficulties.
“So staring is draining, plus things come up which interfere with our ability to monitor, and our mind leaves the premises even when none of the other things are an issue. It’s a trifecta of things working against effective monitoring.”
For the study, published in the journal Consciousness and Cognition, researchers examined why monitoring failures happen even among experienced and highly trained airline pilots. They asked 16 commercial jet pilots to monitor the progress of a simulated routine flight in which high levels of cockpit automation handled the tasks of navigating and steering the airplane.
Knowing that past experiments had shown monitoring—essentially sitting and staring at computer screens—to be a tiring process that quickly leads to fatigue and inattention, the researchers wanted to know how the pros do it: Did they have strategies to fend off the fatiguing effects of long watches?
They found that the cockpit environment is busy enough that pilots are often sidetracked by other tasks, such as talking to air traffic control or configuring the airplane’s systems, which curtail fatigue. But they also discovered that these pop-up tasks could themselves cause pilots to miss important events during flight.
Most interesting, is what happened when the pilots weren’t interrupted. Rather than focusing solely on monitoring the flight, they instead created their own distractions by engaging in what the researchers call “mind wandering.”
When periodically asked what they were thinking about, pilots admitted to thinking “task-unrelated thoughts” up to 50 percent of the time—mental excursions that frequently led to missed events in flight. All in all, the pilots missed 25 percent of all altitude crossings they were charged with monitoring.
The pilots tried to limit their mind wandering to times when there were fewer demands on their attention, but ultimately found that even in circumstances with high demand their minds routinely wandered.
“We had anticipated that the longer people monitored that in itself would be associated with inferior performance, and we actually didn’t observe that particular pattern,” Schooler says. “But we had failed to appreciate how the solution—the interruption—itself compounds the problem. We were also surprised at the sheer number of times that pilots missed the altitude callouts and the high frequency with which they admitted to mind wandering.
“We should be very wary of relying on people to serve in a monitoring capacity—especially now, when we do have technology that can fill the monitoring role,” he says.
Real-world monitors may be caught between a continuous-vigilance approach that is doomed to fail, a dynamic environment that cannot be fully controlled, and what may be an irresistible urge to let one’s thoughts drift, says Steve Casner, a research psychologist with NASA.
“This task of watching over a computer system while it works is incredibly trying, if not impossible, for a human being to do well. You can try paying attention, and you can try taking brief breaks, but sooner or later you’ll miss something important.
“This is a job for a robot, not a human being. It’s time to rethink the way we design these systems. Let the people do the stuff they are good at, and let the computers handle the mundane chores.”