Test Your Sleep IQ.

Find out how much you know about how you spend a third of your time--asleep.

The following true or false statements test what you know about sleep. Be sure to read the correct answers and explanations that follow.

1. Sleep is a time when your
   body and brain shut down
   for rest and relaxation.

   [] TRUE    [] FALSE

2. If you regularly doze off
   unintentionally during the
   day, you may need more
   than just a good night's
   sleep.

   [] TRUE   [] FALSE

3. If you snore loudly and
   persistently at night and
   are sleepy during the day
   time, you may have a sleep
   disorder.

   [] TRUE    [] FALSE

4. Opening the car window
   or turning the radio up
   will keep the drowsy driver
   awake.

   [] TRUE   [] FALSE

5. Narcolepsy is a sleep
   disorder marked by
   "sleep attacks."

   [] TRUE    [] FALSE

6. The primary cause of
   insomnia is worry.

   [] TRUE    [] FALSE

7. One cause of not getting
   enough sleep is restless
   legs syndrome.

   [] TRUE   [] FALSE

8. The body has a natural
   ability to adjust to
   different sleep schedules,
   such as working different
   shifts or traveling through
   multiple time zones quickly.

   [] TRUE   [] FALSE

9. People need less sleep as
   they grow older.

   [] TRUE    [] FALSE

10. More people doze off at
    the wheel of a car in the
    early morning or midafternoon
    than in the evening.

    [] TRUE   [] FALSE

Answers to the Sleep IQ Quiz

1. FALSE. Although it is a time when your body rests and restores its energy levels, sleep is an active state that affects both your physical and mental well-being Adequate restful sleep, like diet and exercise, is critical to good health. Insufficient restful sleep can result in mental and physical health problems and possibly premature death.

2. TRUE. Many people doze off unintentionally during the day despite getting their usual night of sleep. This could be a sign of a sleep disorder. Approximately 40 million Americans suffer from sleep disorders, including sleep apnea, insomnia, narcolepsy, and restless legs syndrome. An untreated sleep disorder can reduce your daytime productivity, increase your risk of accidents, and put you at risk for illness and even early death.

3. TRUE. Persistent loud snoring at night and daytime sleepiness are the main symptoms of a common and serious sleep disorder, sleep apnea. Another symptom is frequent long pauses in breathing during sleep, followed by choking and gasping for breath. People with sleep apnea don't get enough restful sleep, and their daytime performance is often seriously affected. Sleep apnea may also lead to hypertension, heart disease, heart attack, and stroke. However, it can be treated, and the sleep apnea patient can live a normal life.

4. FALSE. Opening the car window or turning the radio up may arouse a drowsy driver briefly, but this won't keep that person alert behind the wheel. Even mild drowsiness is enough to reduce concentration and reaction time. The sleep-deprived driver may nod off for a couple seconds at a time without even knowing it--enough time to kill himself or someone else. It has been estimated that drowsy driving may account for an average of 56,000 reported accidents each year--claiming more than 1,500 lives.

5. TRUE. People with narcolepsy fall asleep uncontrollably--at any time of the day, in all types of situations--regardless of the amount or quality of sleep they've had the night before. Narcolepsy is characterized by these "sleep attacks," as well as by daytime sleepiness, episodes of muscle weakness or paralysis, and disrupted nighttime sleep. Although there is no known cure, medications and behavioral treatments can control symptoms, and people with narcolepsy can live normal lives.

6. FALSE. Insomnia has many different causes, including physical and mental conditions and stress. Insomnia is the perception that you don't get enough sleep because you can't fall asleep or stay asleep or get back to sleep once you've awakened during the night. It affects people of all ages, usually for just an occasional night or two, but sometimes for weeks, months, or even years. Because insomnia can become a chronic problem, it is important to get it diagnosed and treated if it persists for more than a month.

7. TRUE. Restless legs syndrome (RLS) is a medical condition distinguished by tingling sensations in the legs--and sometimes the arms--while sitting or lying still, especially at bedtime. The person with RLS needs to stretch or move the legs constantly to try to relieve these uncomfortable or painful symptoms. As a result, he or she has difficulty falling asleep or staying asleep and usually feels extremely sleepy and unable to function fully during the day. Good sleep habits and medication can help the person with RLS.

8. FALSE. The human body's biological clock programs each person to feel sleepy during the nighttime hours and to be active during the daylight hours. So people who work the night shift and try to sleep during the day are constantly fighting their biological clocks. This puts them at risk of error and accident at work and of disturbed sleep. The same is true for people who travel through multiple time zones quickly; they get "jet lag" because they cannot maintain a regular sleep-wake schedule. Sleeping during the day in a dark, quiet bedroom and getting exposure to sufficient bright light at the right time can help improve daytime alertness.

9. FALSE. As we get older, we don't need less sleep, but we often get less sleep. That's because our ability to sleep for long periods of time and to get into the deep restful stages of sleep decreases with age. Older people have more fragile sleep and are more easily disturbed by light, noise, and pain. They also may have medical conditions that contribute to sleep problems. Going to bed at the same time every night and getting up at the same time every morning, getting exposure to natural outdoor light during the day, and sleeping in a cool, dark, quiet place at night may help.

10. TRUE. Our bodies are programmed by our biological clock to experience two natural periods of sleepiness during the 24-hour day (regardless of the amount of sleep we've had in the previous 24 hours). The primary period is between about midnight and 7:00 a.m. A second period of less intense sleepiness is in the midafternoon, between about 1:00 and 3:00. This means that we are more at risk of falling asleep at the wheel at these times than in the evening--especially if we haven't been getting enough sleep.

Reprinted with permission from the National Heart, Lung, and Blood Institute. For more information on sleep, contact: NHLBI Information Center, P.O. Box 30105, Bethesda, MD 20824-0105; phone: [phone]; fax: [phone].