Tossing and turning the night before a big presentation at work, or going without sleep for reasons you just can't explain -- there's little doubt that failure to get a good night's sleep leaves you groggy and dazed, at best. But the cognitive effects of sleep deprivation, whether you miss an entire night or just an hour each evening, could cost you in ways you never imagined.
Evidence from University of California--San Diego researchers suggests sleep times are directly linked to earnings. Their findings, currently under review, found that sleeping one extra hour each night increased average earnings by 16 percent. For their average study participant, this meant an extra $6,000 per year.
"The worst bout of insomnia I've had in my life, I went five nights without sleeping," recalls 36-year-old Amanda McCauley of Omaha, Nebraska. "I was on a business trip, so I had to work the entire time. I had to be up, moving around, engaging and productive pretty early in the morning, and pull a few late nights."
McCauley, who works in IT, says she hasn't seen the long-term effects of her sleepless nights, but knows her insomnia has definite mental effects, which, in turn, affect her at work.
"I have to try and keep busy [on those days], because if I don't keep busy, that's when I start to suffer," she says.
Sleep and Your Mind
The cognitive skills we depend on in our professional lives are affected when we fail to get good sleep. Our abilities to focus and concentrate, reason, remember and make good judgment calls all suffer. Emerging research suggests our brains depend on a nightly bath of sorts to keep them functioning at their best.
"It's been coined the glymphatic system," says A. Thomas Perkins, a sleep expert and director of the Sleep Medicine Program at Raleigh Neurology in Raleigh, North Carolina. "This system sort of flushes the brain of all metabolic waste, and it does this every night, getting in between the cells and neurons, purging the brain of the metabolic byproducts of the day."
In 2013, a team of researchers at the Center for Translational Neuromedicine at the University of Rochester Medical Center in New York found that the brain actually makes room for this nightly flushing of cerebrospinal fluid. Space between brain cells increases during sleep, letting it essentially wash the brain of "toxic molecules."
Perkins explains that not getting enough sleep or not sleeping deeply enough hinders your brain's ability to perform this nightly flush, possibly leading to the cognitive effects you experience the next day.
"You essentially have a brain trying to function the next day with junk laying around -- metabolic byproduct and wastes that interfere with its functioning," he says.
When your job involves major responsibilities, a lack of sleep could be disastrous. The explosion of the space shuttle Challenger, the Three Mile Island and Chernobyl disasters, the Exxon-Valdez oil spill and the 2013 deadly Bronx commuter train derailment were all blamed, at least in part, on fatigue.
For the average person, a lack of sleep could translate to the inability to focus on what's being said at a meeting, to pull information together into an important report or to engage with co-workers in a collaborative and collegial manner.
Effects on Work Relationships
"Once I hit the pillow, I'll be knocked out right away," says 47-year-old Ruthie Williams, a social worker in a skilled nursing facility in Wilmington, North Carolina. "It's torture because sometimes I feel like, 'Oh, this is going to be a good night; this is it,' and then a few hours later, I'm wide-awake."
Williams averages between three and five hours of sleep each night. Her days are punctuated by periods of high energy and extreme exhaustion at the most inopportune times. For her, a lack of sleep means a shorter temper, something her co-workers might experience more often than she, or they, would like.
"I'm already Type A, but when I'm tired, I'm just in a bad mood," she says. "I can feel myself being snappy."
McCauley has similar problems when operating without sleep, and lets her team know when she's feeling the effects of her insomnia.
"It makes me have a short fuse, so I may be shorter or even curt in an email response," she says. "On those days, I have to tell people that I haven't slept in three nights, or that I'm a little out of my head today."
Neither woman thinks her sleep problems are affecting her career long-term; both make an effort to counter-balance the potentially negative mental health outcomes. But it's possible, when surrounded by a better-rested workforce, that their lack of sleep could put them at a disadvantage at the office.
Catching Up On ZZZ
For some people, lack of sleep isn't a matter of insomnia, but lack of time. The gold standard for sleep is six to eight hours nightly, and evidence suggests the average American adult is getting at least that much. But just depriving yourself of an hour a night adds up and can have cumulative effects on your mental status throughout the week.
"Fortunately, recovery sleep works," Perkins says. "So you can be chronically sleep deprived for weeks in a row, and have a few long nights' sleep and a nap and sort of boom, you're caught up. In other words, you don't have to make up what you miss in a 1:1 ratio."
But it's not that simple for people such as Williams and McCauley.
"People want a quick fix, and they ingrain a bunch of bad habits," Perkins says.
Going to bed early and staring at the ceiling does nothing to train your brain for more efficient sleep, and taking a hot bath raises your core body temperature when your body actually requires a half-degree drop in temperature to trigger its nightly shut down.
Perkins says the answer for many insomniacs is a sort of boot camp for sleep, including cognitive behavioral therapy and sleep restriction to make people more-efficient sleepers. But this definitely isn't a quick fix, and programs typically last six to eight weeks, with participants needing to practice their new sleep skills every night indefinitely.
And for those people who say they just function better on less than the recommended hours of sleep?
"They're full of it," Perkins says. "It's like saying, 'I don't need eyeglasses,' but you didn't realize you needed them until you had corrective lenses to compare what you're currently seeing to what you ought to be seeing. They don't have a reference point for normal sleep and refreshment."
The next time you're tempted to work late and burn the midnight oil, or rise to beat all of your co-workers to the office, remember: sacrificing sleep could actually put you at a disadvantage. Putting in regular hours with a clear mind is more beneficial than overtime on limited sleep, and you'll feel healthier for it.