You can only will yourself to stay awake for so long. Eventually, the brain decides it has had enough and you'll conk out.
In the wake of the problems with air traffic controllers snoozing on the job, Morning Edition host Mary Louise Kelly talks with Harvard sleep specialist Dr. Charles Czeisler about the limits of human endurance — especially for people on the night shift.
Czeisler tells Kelly that people can adapt to overnight work, but it's pretty hard to do. There's the problem of the sun not being out at night (at least for most of the world most of the time) and human nature. On their days off, people who work nights tend to switch back to the daytime schedules their friends and families keep.
That flip-flopping makes it difficult for the workers to stay alert at night.
The way overnight work is scheduled and inflexibility about napping on the job have complicated the problem, Czeisler says. "The environment has changed dramatically over the last 50 years, requiring people to stay continuously awake in jobs they often were able to sleep at in times gone by," he explains.
Just to be clear, chronic sleepiness isn't confined to those on the graveyard shift. A survey by the Centers for Disease Control and Prevention found that more a third of Americans had less than 7 hours of sleep the night before they were questioned. And 38 percent of respondents said they had fallen asleep without meaning to during at least one day in the previous month.
There are public health consequences from the national sleep deficit. "Every week nearly 2 million Americans nod off or fall asleep while driving their cars on the highways," Czeisler says.
We're only human, after all. And despite illusions that "we should be able to burn the candle at both ends" without paying a price, Czeisler says, "at some point, the brain seizes control and we involuntarily make the transition from wakefulness to sleep — even at very inappropriate circumstances."
So when it comes to critical workers, such as pilots and air traffic controllers, what should we do? Transportation Department Secretary Ray LaHood recently said air traffic controllers shouldn't be allowed to nap during paid breaks on the job.
But a prohibition like that doesn't make sense to Czeisler, who said in that case controllers wouldn't be able to "do the one thing that would help prepare them for work, when they're on break, which would be to take a brief nap."
They can smoke or eat on break, so why not sleep a little? In Czeisler's view, it would be far better to recognize that naps are going to happen and to schedule them, rather than to have people doze off at unscheduled times.