Sleep Matters

http://sciencecareers.sciencemag.org/

Forty Winks: Science and Sleep

Irene S. Levine
United States
28 July 2006

Do you tend to hit the snooze button on your alarm clock several times before getting out of bed? Does it take you forever, on certain days, to get yourself together before you leave the house? How many mornings have you decided that you need an extra cup of coffee just to get started, or an afternoon slug of espresso to make it through the day?

Do you ever take catnaps at your desk during lunch hour? Are there times when your patience runs so thin that you can barely listen to the stories of a colleague whose company you ordinarily enjoy? Do you recall snapping at your supervisor or your partner only to regret it moments--or days--later? Do you fall asleep in front of the TV when you come home from the lab? These can all be signs of a sleep deficit, which can cause a number of different problems if you choose to overlook them.

Recently, I attended a late-afternoon lecture given by a visiting scholar I had been looking forward to hearing. As the lights dimmed and he began his PowerPoint presentation, I felt my eyelids closing. As my chin fell onto my chest, I don't know whether I was more startled or mortified. As I looked around to see whether the speaker or anyone else in the small group had noticed, my heart was pounding. The fear of a recurrence kept me vigilant for the rest of the lecture.

This event made it clear that I desperately needed more sleep. I had already started to have some suspicions: The night before, I had worked on a manuscript until well past 2 a.m. without making much progress. Before I succumbed and called it a (very long) day, I had wasted hours rifling through journal articles and staring at my computer screen with little to show for my efforts.

Cutting back on sleep is a common problem. The relentless pressure to achieve drives many early-career scientists and science trainees to push themselves even harder than most. Many of us feel like there aren't enough hours in the day or days in the week. So we cheat on sleep in an effort to steal extra time. "Sleep deprivation has evolved into an epidemic of sorts," says Nancy Foldvary-Shaefer, a sleep researcher who is director of the Sleep Disorders Program at the Cleveland Clinic in Ohio and author of Getting a Good Night's Sleep: A Cleveland Clinic Guide.

Running on empty

"I'm embarrassed to admit that I am one of the science trainees that cheat on sleep," says a postdoc engineer working at a European university. "I don't think I've had a regular sleeping pattern since I left my parents' house for college a decade ago." This postdoc used to work in libraries or computer labs until the wee hours of the morning. Even today, he doesn't make it to bed until 4 a.m. whenever a fellowship or job application is due.

Earlier this year, a panel of experts convened by the Institute of Medicine (IOM) produced a report entitled Sleep Disorders and Sleep Deprivation: An Unmet Public Health Problem. The report notes that in recent years, people have started working longer and spending more time on the Internet and watching TV--and sleeping less. Even those who are zealous about eating healthy food and exercising to stay fit view sleep as, in the authors' words, "an expendable luxury."

Sleep experts, on the other hand, consider sleep a necessity. "It is one of the body's most basic functions, responsible for restoring and preserving our health," says Foldvary-Schaefer. Located in the brain, a "sleep switch" as she calls it helps the body maintain a balance between sleep and wakefulness. Our internal clock regulates the sleep-wake cycle in conjunction with the lightness and darkness in our environment, she explains. Some sleep disorders arise when the body's drive for sleep--known as the homeostatic drive--and the environment are out of sync. Others arise when sleep is disrupted by abnormal breathing patterns, body movements, or abnormally elevated levels of mental activation or muscle tension.

The amount of sleep needed by each individual is genetically predetermined. Although these needs may change over the life span, they can't be reset at will. Most people require about 7 to 8 hours of sleep, although some require as little as 5 and others more than 9. Whatever your needs, a loss of 90 minutes of sleep a night has been shown to reduce daytime alertness by a third.

"From military service, we know that soldiers can recruit enough energy and motivation to stay awake for several days if the need arises," says Peretz Lavie, head of the Technion Sleep Research Laboratory in Haifa, Israel. "But such a schedule cannot be maintained for long."

Tips for a Good Night's Sleep (From Dr. Robert Fayle, medical director of The Sleep Center at Park Plaza Hospital and Medical Center in Houston, Texas, U.S.) Sleep only as much as you need to feel refreshed the next day. Get up at the same time, 7 days a week. Exercise regularly. Make sure your bedroom is comfortable and free of disturbing light and noise. Make sure that your bedroom is at a comfortable temperature during the night. Eat regular meals and do not go to bed hungry. Avoid excessive fluids in the evening. Cut down on caffeine products. Avoid alcohol, especially in the evening. Smoking may disturb sleep. Don't take your problems to bed. Train yourself to use the bedroom only for sleeping and sexual activity. Do not TRY to fall asleep. Put the clock under the bed or turn it so that you cannot see it. Avoid taking naps.

Too little, too late

The signs aren't always obvious, but an accumulating sleep deficit extracts a huge toll physically as well as emotionally. The most common symptom of a lack of sleep is daytime sleepiness, but other signs include loss of temper, irritability, depressed mood, lack of motivation, impaired attention, memory lapses, and interpersonal conflicts. "Immediate effects involve mood first; more sleep loss tends to affect cognitive faculties next, and then motor performance, such as falling asleep driving and occupational accidents," says Foldvary-Schaefer.

Researchers at Drexel University College of Medicine in Philadelphia, Pennsylvania, surveyed close to 2000 academic physicians and basic science faculty members at four medical schools in the United States to determine whether work-related stressors in academic medicine negatively affected the physical and emotional health of these scientists. The study, led by Barbara A. Schindler, vice dean for education and academic affairs, and published in January in Academic Medicine, concluded that high levels of depression, anxiety, work strain, and job dissatisfaction were common among faculty members, especially among younger faculty members and surgeons. Although the study did not establish any causal effect, another key finding was that an overwhelming majority--77% of those surveyed--reported not getting adequate sleep.

A University of Florida (UF) study, to be published in the October issue of the Journal of Management, reports on 45 employees at a large insurance company who were asked to keep a Web log recording their level of work satisfaction, the extent to which they suffered sleep problems, and how often they experienced certain emotions. The study, led by Brent Scott, a UF Gainesville graduate student in management, found that lack of sleep was associated not only with crankiness and fatigue but also with work dissatisfaction. "It's intuitive that one might feel a little irritable, but to experience emotional spillover to the point of actually feeling less satisfied with work is a little surprising," says Scott.

These effects were more pronounced in women, who experienced more fatigue and hostility and were less attentive and happy overall than their male counterparts. Explanations for the gender divide aren't clear, but we know that societal expectations vary for the sexes and that women are more likely to express emotion than men.

Scott attributes the problems across both sexes to workplace pressures. "With employers trying to squeeze every last bit of productivity out of employees and having them work extended hours, a 40-hour week is basically nonexistent anymore in some occupations," he says. He calls for more flexible scheduling, on-site childcare, and wellness programs that help employees avoid and better cope with sleep problems.

Disordered sleep

According to IOM, most sleep deficits can be attributed to one of two categories, which sometimes overlap: occupational/lifestyle factors or diagnosable sleep disorders. As much as a third of the general population suffers from one of the 80 sleep disorders (such as insomnia, sleep apnea, narcolepsy, restless legs syndrome, and circadian rhythm disorders) recognized by the American Academy of Sleep Medicine.

"Some of us don't choose to miss sleep to achieve a goal," says a chemist who works in an analytical service lab. "In my case, I have dealt with insomnia all my life. Carelessness in the lab due to being sleepy, and accidents in all aspects of my life, are a normal headache for me," he adds.

The IOM report documents the individual and public health consequences of chronic sleep deficits and sleep-related disorders, which can be devastating. They are associated with a range of adverse health outcomes including an increased risk of hypertension, diabetes, obesity, heart attacks, and stroke. The report cites the tragedies at the Union Carbide chemical plant in Bhopal, India, and the nuclear reactor meltdowns at Three Mile Island and at Chernobyl as catastrophes that were attributed, at least in part, to fatigue-related lapses in performance. The report estimates that in the United States alone, 110,000 motor vehicle injuries and 5000 fatalities are sleep-related, independent of any alcohol effects.

An ounce of prevention

Given how important sleep is to your health and emotional well-being, it makes sense to monitor your own schedule and make sure you aren't operating at a loss. Sometimes, simple changes in your routine can result in better sleep. If your problem persists for a month or longer, you should talk to your doctor to rule out an underlying medical condition or a diagnosable sleep disorder. "Supervisors can play a very important role by calling attention to inadvertent napping, accidents, workplace conflicts, and to those who nap on breaks and over lunch hour," says Foldvary-Shaefer.

"I learned as an undergrad that sleep and food are the two things, in order of priority, that I need to be productive," says a U.S. medical student. "Living in a noisy dorm, I was chronically sleep-deprived, and it definitely influenced the quality of my work, in addition to making me depressed."

"I have repeatedly tried to trade sleep for other things that (it seems) I want more," says an assistant professor at a large research university. "Nevertheless, after the last 3 to 5 years, I think I can say with some authority, giving up sleep is not the way to accomplish them. I'd rate lack of consistent sleep as the single most consistent detractor of my productivity, with lack of consistent exercise and diet being in close competition for the second slot."

So the next time someone walks up to you saying something stupid like, "If you snooze, you lose," don't listen. Just make sure that you are getting enough sleep that you have enough energy and enthusiasm to tackle the day.