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Sleep Disorders


One-third of all adult Americans--about 50 million people--complain about their sleep. Some sleep too little, some fitfully, and some too much. Although one-third of our lives is spent asleep, most of us don't know much about sleep, not even our own. We don't even know exactly why we sleep, other than--like an overnight battery recharge--sleep promotes daytime alertness. Sleep problems profoundly disturb both sleeping and waking life. What is the significance of these problems and what can be done about them? Recent scientific research is beginning to provide some of the answers.

The Balm Of The Bard

Sleep was, for Shakespeare, the "balm of hurt minds, great nature's second course, chief nourisher in life's feast." For centuries, science knew little more: sleep was a magical phenomenon. Not until the 1930s was it shown to possess a secret life. Only then did investigators, using the electroencephalogram (EEG), measure the brain's electrical activity in sleeping subjects. On rivers of graph paper, they could watch the rhythm of activity in the brain during sleep. They discovered that these biological rhythms naturally Fall into different states, stages, and cycles. Instead of being a quiet and peaceful period of rest and recuperation, as most of us think of it, sleep is a very complex, dynamic activity. Your body may be the picture of tranquillity while you sleep. But, in fact, numerous biochemical, physiological, and psychological events are constantly taking place.

How Long To Sleep

Most adults sleep between 7 and 8 hours. But no one really knows how much sleep we need. Sleep duration varies widely. A natural "short sleeper" may sleep for only 3 or 4 hours, and actually function worse with more sleep. A "long sleeper," on the other hand, may need more than 10 hours. "Variable sleepers" seem to need more sleep at times of stress and less during peaceful times. Changes with age also contribute to changes in the ability to sleep continuously and soundly. A newborn infant may sleep 16 hours a day, an adolescent may sleep very deeply for 9 or 10 hours straight, while an elderly person may take daytime naps and then sleep only 5 hours a night. With advancing age, some people switch to shorter days and some to longer ones. Such a switch may be simply a normal condition of aging. Or, it may result From shifts in daily patterns, retirement, or changes in the person's physical or mental health.

In general, sleep is helped by two factors--being tired at bedtime and being in tune with your own internal clock. Sleep may be difficult or less satisfying if it occurs at a time when the biological clock says, "It's time to be awake."

To find out how much sleep you need, try to determine your own sleep pattern. You should feel sleepy about the same time every evening. If you frequently have trouble staying awake in the daytime, you may not be sleeping long enough. Or perhaps you are not sleeping well enough. Both the quantity and quality of sleep and wakefulness are important. You are sleeping as much as you need if, during your waking hours, you are alert and have a sense of well-being.

Insomnia: A Symptom, Not an Illness

Insomnia, the most common sleep complaint, is the feeling that you have not slept well or long enough. It occurs in many different forms. Most often it is characterized by difficulty falling asleep (taking more than 30 to 45 minutes), awakening frequently during the night, or waking up early and being unable to get back to sleep.

With rare exceptions, insomnia is a symptom of a problem, and not the problem itself. Good sleep is a sign of health. Poor sleep is often a sign of some malfunctioning and may signal either minor or serious medical or psychiatric disorders. Insomnia can begin at any age. And, it can last for a few days (transient insomnia), a few weeks (short-term insomnia), or indefinitely (long-term insomnia).

Causes Of Insomnia

Transient insomnia may be triggered by stress--say, a hospitalization for surgery, a final exam, a cold, headache, toothache, bruised muscles, backache, indigestion, or itchy rash. It can also be caused by jet travel that involves rapid time-zone change.

Short-term insomnia, lasting up to 3 weeks, may result from anxiety, nervousness, and physical and mental tension. Typical are worries about money, the death of a loved one, marital problems, divorce, looking for or losing a job, weight loss, excessive concern about health, or plain boredom, social isolation, or physical confinement.

Long-lasting distress over lack of sleep is sometimes caused by the environment, such as living near an airport or on a noisy street. Working a night shift can also cause problems: sleeping during the day may be difficult on weekdays, especially when the person sleeps at night on weekends. But more often, long-term insomnia stems from such medical conditions as heart disease, arthritis, diabetes, asthma, chronic sinusitis, epilepsy, or ulcers. Long-term impaired sleep can also be brought on by chronic drug or alcohol use, as well as by excessive use of beverages containing caffeine and abuse of sleeping pills.

Sometimes (as we shall see), long-term sleep difficulty can result from a number of other directly sleep related medical ailments that are more directly related to sleep. Some examples are sleep apnea, nocturnal myoclonus, or "restless legs" syndrome.

Many patients with long-term insomnia may be suffering from an underlying psychiatric condition, such as depression or schizophrenia. Depression, in particular, is often accompanied by sleep problems (which usually disappear when the depression is treated). People with phobias, anxiety, obsessions, or compulsions are often awakened by their fears and worries, sometimes by nightmares and feelings of sadness, conflict, and guilt.

Sleep Hygiene: A First Move Against Insomnia

Insomnia is a complex problem, not given to simple solutions. Most experts agree that treatment should start with assessing and correcting sleep hygiene and habits.


Regular exercise tends to benefit sleep, but not right at bedtime. Vigorous exercise, especially just before sleep, can cause arousal and delay sleep. You cannot force sleep on a given night by exercising excessively during the day. Exercise in the morning also has little beneficial effect on sleep. The best time to exercise is in the afternoon or early evening. But, even then, it probably won't help you sleep unless you exercise on a regular schedule.

Trying Too Hard

Trouble falling asleep, the most common form of sleep disturbance, may be brought on simply by going to bed too early. Sleep cannot be forced. You should not go to sleep until you are sleepy. If you turn in too early--even if you do fall asleep--you could experience a disturbed night's rest or could wake early without feeling refreshed. If you go to bed when you feel sleepy but find that you can't fall asleep, don't stay in bed brooding about being awake. It is best to get out of bed. Leave the bedroom. Read, sew, watch TV, take a warm bath, or find some other way to relax before slipping between the sheets once more.


Laboratory tests have shown that daytime naps disrupt normal nighttime sleep. Although many people feel like napping between 2 and 4 p.m. (siesta time), most sleep better if they don't nap during the day. Naps should not be used as a substitute for poor sleep at night. However, there are exceptions to this general rule. Many older people, in particular, do sleep better at night when they take daytime naps. But if you are a napper who sleeps poorly at night, your nighttime sleep might improve if you skip the naps.

Bedtime Snacks

If hunger keeps you awake, a light snack might help you sleep, unless it causes problems with digestion. Avoid heavy meals, alcohol, and caffeine-containing coffee, tea, and cola. For those who can tolerate milk, that old, time-tested remedy may work best.

Smoking At Bedtime

Nicotine stimulates the nervous system and can interfere with sleep. In one sleep laboratory study, smokers experienced greater difficulty than nonsmokers. Sleep patterns also improved significantly among chronic smokers when they abstained from smoking.


The effect of alcohol is deceiving. It may induce sleep, but chances are it will be a fragmented sleep. The sleeper will probably wake up in the middle of the night when the alcohol's relaxing effect wears off.

Regular Bedtime

The best way to sleep better is to keep a regular schedule for sleeping. Go to bed at about the same time every night, but only when you are tired. Set your alarm clock to awaken you about the same time every morning--including weekends and regardless of the amount of sleep you have had. If you have a poor night's sleep, don't linger in bed or oversleep the next day. If you awaken before it is time to rise, get out of bed and start your day. Most insomniacs stay in bed too long and get up too late in the morning. By establishing a regular wakeup time, you help solidify the biological rhythms that establish your periods of peak efficiency during the 24-hour day.

Sleeping Pills: A Temporary Solution

According to the latest evidence, the medical profession is becoming increasingly conservative in prescribing sleep-promoting medications. Over the past decade, prescriptions filled in drugstores have dropped from 42 to 21 million. Only about 10 percent of people with insomnia receive prescribed sleeping pills. Another 5 percent buy over-the-counter sleep compounds that don't require a prescription. Still others use drugs intended for other purposes--for example, daytime sedatives, antihistamines, anticholinergic drugs, and tranquilizers. None of these drugs should be used without consulting a physician first. Their misuse or outright abuse poses a danger. All sleeping medications should be used sparingly, for the shortest possible time, and in the smallest effective dose.

Prescribed Sleeping Pills

All brands of prescribed sleeping pills are hypnotics--that is, drugs that depress the central nervous system and put users to sleep. A variety of hypnotics are now on the market, including barbiturates, benzodiazepines, and several classes of drugs generally referred to as the nonbarbiturates/nonbenzodiazepines.

The barbiturates usually lose their effectiveness within 2 or 3 weeks of daily use. Doctors today tend not to prescribe the barbiturates. Most prefer to treat their patients with one of the benzodiazepines or a variant class of drug, which are considered less addictive and safer in overdose than barbiturates. The benzodiazepines are still very toxic, however, when taken in combination with alcohol, overdoses are taken or when respiratory disorders. Benzodiazepine drugs sometimes can aid sleep for up to 30 days. The benzodiazepines are not all alike, though. Some work faster than others, some produce effects that last longer, and some are eliminated from the body sooner.

Which type of sleeping pill is prescribed depends on a person's particular problem and needs. One pill might be right for problems falling asleep and another for problems in maintaining sleep or insomnia associated with anxiety.

Do Sleeping Pills Help?

When taken For a brief period and under a doctor's guidance, prescription sleeping pills may help you sleep better. But insomnia cannot be corrected with pills. At best, sleeping pills have only limited usefulness. They provide a temporary solution to insomnia. Thus, only when a person's health, safety, and well-being are threatened should drugs be sleep-promoting considered and then only after the doctor takes a medical history and does a physical examination. He or she might identify conditions that should not be treated with sleeping pills and weigh other risks drug treatment.


Although temporarily helpful, sleep promoting medications can eventually cause disturbed sleep, side effects, a sleep "hangover" during the day, and dependence on the drug. Further more, once the drugs are stopped, sleep problems return, at least temporarily, and may be even more severe than they were before the medication was First taken. Clearly, the regular, long-term use of sleeping pills should usually be avoided.

Sleeping pills can be fatal when taken in combination with alcohol or other drugs. Even when not fatal, combining drugs and alcohol can be perilous to driving and the use of other machinery. Long-acting sleeping pills, by themselves, may also impair driving performance the day after they are taken. People who are taking sleeping pills should never drink for a couple of days afterward.

Sleeping Pills For The Elderly

Many people over 60 are dissatisfied with their sleep. While they make up about 14 percent of the population, they consume about 20 to 45 percent of all sleep medications.

Toxic (poisonous) drug reactions occur more frequently in the elderly than in the young. In addition to their frequent use of sleeping pills, many older people also take other medications prescribed by their doctors. Combining sleeping pills and other drugs poses an increased hazard for the elderly because of changes in bodily functioning that accompany aging. The elderly tend to absorb and excrete all medications more slowly than younger people and usually require smaller doses. Their nervous systems may also be more sensitive, which, in turn, may increase the effects of combining drugs.

Sleeping pills may cause older people to stumble or fall, feel groggy or hung-over, or appear forgetful and senile. Before turning to sleep medications, older people (like people of any age) should consult their doctor and first seek help to the underlying cause of the sleep problem.

Sleeping Pills And Pregnant Women

Pregnant women should be aware that sleeping pills may be harmful to their infants. If a woman is pregnant or intends to become pregnant, she should ask her physician whether it is safe or advisable to use any drug.

She also should learn about the effects of every drug, including cigarettes and alcohol, on her and her unborn baby.

Sleep Disorders: A National Health Problem

Sleep disturbances place an uncalculated, but enormous, burden on the American public. Many industrial and automobile accidents are related to undiagnosed and untreated disorders of sleep. School and job performance, and even everyday social relationships, are also affected. Most sleep disorders, whether caused by physical or mental factors, can be treated or managed effectively once they are properly diagnosed.

Anxiety, Depression, And Sleep

In a recent national survey, 47 percent of those reporting severe insomnia reported a high level of emotional distress. Psychological factors, such as fears, phobias, and compulsions, can so occupy the mind that sleep is delayed, disturbed, or shortened. Chronically tense people are frequently so restless, hyperactive, and apprehensive that they expect not to sleep when they go to bed.

In depressed people, an overwhelming feeling of sadness, hopelessness, worthlessness, or guilt can be associated with abnormal sleep patterns. Often, the depressed person awakens early and cannot return to sleep. Yet, sometimes, just the opposite is true. Some depressed people find relief in sleeping, denying or escaping from the problems of living by sleeping. The loss of a sense of purpose in life may be associated with an overwhelming urge to sleep, a constant feeling of tiredness, or nighttime sleep marked by an irregular sleep/wake pattern.

Many depressed people complain of insomnia without recognizing they are depressed. If you have lost interest in activities you used to enjoy, or if you have feelings of hopelessness or suicidal thoughts, you may be one of them. You should discuss the problem with your physician, who may recommend psychiatric consultation. While the complaint may be insomnia, the underlying depression, not the insomnia, must be treated. Antidepressant medications and/or psychotherapy can produce remarkable improvement, both in mood and sleep patterns.


Snoring is a sign of impaired breathing during sleep. The older you get, the more apt you are to snore. Almost 60 percent of males in their 60s and 45 percent of females are habitual snorers--in all, one in eight Americans. Light snoring may be no more than a nuisance. But, snoring that is loud, disruptive, and accompanied by extreme daytime sleepiness or sleep attacks should be taken very seriously. Such snoring may be a sign that a person is suffering from the life-threatening condition called sleep apnea--a blockage of breathing during sleep.

Sleep Apnea

Discovered only recently, sleep apnea is believed to affect at least 1out of every 200 Americans, 70 to 90 percent of them men, mostly middle-aged, and usually overweight. But the condition can afflict both men or women at any age.

People with this disorder actually may stop breathing while asleep-even hundreds of times--without being aware of the problem. During an apnea attack, the snorer may seem to gasp for breath, and the oxygen level in the blood may become abnormally low. In severe cases, a sleep apnea victim may actually spend more time not breathing than breathing and may be at risk for death.

In the most common form of the condition, obstructive apnea (also called upper airway apnea), air stops flowing through the nose and mouth, but throat and abdominal breathing efforts are uninterrupted. The snoring that results is produced when the upper rear of the mouth (the soft palate and the cone-shaped tissue--the uvula--that descends from it) relaxes and vibrates as air passes in and out. This sets up an air current between the palate and the base of the tongue, resulting in snoring. Typically, the individual will wake up, emit a vigorous snort or grunt while gasping for air, then immediately fall back to sleep, only to repeat the cycle.

In another form of the disorder, central apnea, both oral breathing and throat and abdominal breathing efforts are simultaneously interrupted. In a third type of apnea, mixed apnea, a brief period of central apnea is followed by a longer period of obstructive apnea.

Sleep apnea can be recognized by a number of symptoms. As mentioned, loud and intermittent snoring is one warning signal. The person who has sleep apnea may experience a choking sensation, early-morning headaches, or extreme daytime sleepiness, as well. His bed partner or roommate might comment on his excessive body movements or his snorting or gasping for breath during sleep. If the condition is suspected, it should be reported to a physician, who may recommend evaluation by a specialist in sleep disorders. Since sleeping pills may be harmful for people with sleep apnea, they should not be taken if the condition is suspected.

Many people with such conditions as obesity, deviated nasal septum, polyps, enlarged tonsils, large adenoids, or a host of other problems may be particularly likely to develop sleep apnea. Doctors can reliably diagnose the disorder only by monitoring oxygen intake, breathing, and other physical functions while the patient is sleeping.

In mild cases, sleep apnea often responds to medication. Or, in the case of overweight middle-aged males, losing weight may lessen the problem. Another procedure, known as continuous positive air pressure, involves the use of a machine that blows air into the nose during the night, opening the air passages in the throat. Patients with severe sleep apnea may require surgery. One procedure widens the throat. In another, a tracheostomy, which is used in very severe cases, a small hole is made at the base of the neck, below and in front of the Adam's apple. At night, a valve on a hollow tube in the hole is opened so that air can flow directly to the lungs, bypassing the sleep induced upper airway blockage. During the day, the valve is closed, allowing the patient to breathe and speak normally.

Narcolepsy: Sleep Attacks

A sleepy feeling during the day could be caused by insufficient, inadequate, or fragmented sleep, by insomnia, or by boredom, social isolation, physical confinement, or depression. But, if you continually experience excessive daily daytime sleepiness--sometimes expressed as tiredness, lack of energy, and/or irresistible sleepiness--you could be suffering from another little-known, chronic sleep disorder called narcolepsy. According to the American Narcolepsy Association, 1 out of every 100 Americans is afflicted with this disorder. Yet, between 50 and 80 percent of them remain undiagnosed. People with narcolepsy suffer from sleep apnea more often than the general population, although apnea is not a core feature of the disorder.

During a narcoleptic attack, the person may find it physically impossible to stay awake and sleeps for periods ranging from a few seconds to a half hour. An attack can occur while watching TV, reading, or listening to a lecture. More surprising, these sudden attacks of sleep can also strike while walking, eating, riding a bike, or carrying on a conversation.

Despite modern medical knowledge about narcolepsy, people who have such attacks typically do not seek medical attention for years--an average of 5 to 7 years. Usually, narcolepsy starts in the early teen years, but it can strike anyone at any age. At first, the symptoms are rather mild. Gradually, over a period of years, they increase in severity.

Narcolepsy With Cataplexy

Besides the presence of excessive sleepiness, which usually is the first symptom noted, the person suffering from narcolepsy may experience a sudden weakness of the muscles called cataplexy. A cataplectic attack is usually triggered by such emotions as laughter, anger, elation, or surprise. It may be experienced as partial muscle weakness lasting a few seconds or as almost complete loss of muscle control lasting for 1 to 2 minutes. During this period, the victim may be in a state of nearly total physical collapse, unable to move or speak, but still conscious and at least/ partially aware of activity in the immediate environment.

Sometimes, narcolepsy is misdiagnosed as epilepsy. But while epilepsy is often accompanied by loss of bladder and bowel control and tongue biting, narcolepsy is not. More often, the symptoms of narcolepsy are attributed to laziness, malingering, or psychiatric disorder. Job and home life usually suffer when narcolepsy goes untreated.

Narcolepsy, believed to be caused by a defect in the central nervous system, has no known cure. However, after proper diagnosis, the disorder can be effectively managed with drugs.

Hazards Of Narcolepsy

People who have narcolepsy but don't know it represent a serious safety hazard to themselves and others when they drive. They may doze off while waiting for a traffic signal to change, or they may drive to destination and be completely unable to recall how they got there. At least one in every 500 drivers is estimated to be suffering from narcolepsy.

Tragically, many of the drivers may not survive to be diagnosed or counted among the sufferers. Yet, narcolepsy is a major traffic safety problem with a low-cost and easy solution: proper diagnosis and medical care. Diagnosed patients who understand their symptoms appear to be very safe drivers, and their driving can be coordinated with the use of medication.

Nocturnal Myoclonus--Unusual Movement During Sleep

Just before some people fall asleep, they experience an uncomfortable, but not always painful, sensation deep in the thigh, calf, or feet. They usually find that vigorous movement eases the discomfort enough to fall asleep, but they complain of sleepiness and fatigue during the day. These people are generally not aware that such episodes of repetitive leg muscle jerks or muscle twitches--nocturnal myoclonus--are followed throughout the night by hundreds of related awakenings. People with nocturnal myoclonus may have involuntary movement in their legs, in addition to twitches, while trying to relax. This condition, known as "restless leg syndrome," usually occurs in people who also have nocturnal myoclonus.

Like many other sleep disorders, nocturnal myoclonus often goes unrecognized by the person who has it. It is most common in middle-aged and older people. And, it may be inherited. Often a bed partner or roommate must call attention to the characteristic twitches--repeated muscle jerks in which the big toe extends, while the ankle, knee, and, occasionally, the hip flex. Upon awakening, some people with nocturnal myoclonus complain of an itching-crawling sensation in their legs, like "current going through them."

In some cases, these disorders have been associated with too little vitamin E, iron, or calcium, and vitamin and mineral supplements have been used as treatment. In other cases, drugs have been found effective, and, in still other, less-severe cases, relief has come from leg exercises.

Sleep Problems of Children

Most childhood sleep disturbances occur only at certain ages, are temporary, and disappear as the child grows older. While annoying or frightening, they usually are not serious. In some cases, however, abnormal sleeping habits can be a sign of more serious problems requiring medical consultation.


Sleepwalking (somnambulism) is fairly common, especially among children. An estimated 15 percent of all children between the ages of 5 and 12 have walked in their sleep at least once, and most outgrow the disorder. Typically, the child (or adult) sleepwalker sits up, gets out of bed, and moves about in an uncoordinated manner. Less frequently, the sleepwalker may dress, open doors, eat, or go to the bathroom without incident and usually will avoid obstacles. But sleepwalkers don't always make their rounds in safety. They sometimes hurt themselves, stumbling against furniture and losing their balance, going through windows, or falling down stairs.

In children, sleepwalking is not believed to be influenced by psychological factors. In adults, it could indicate a personality disturbance.

Usually, it is enough for parents of sleepwalkers to provide their children with emotional support. They should also lock windows and doors and make sure the child does not sleep near stairways and potentially dangerous objects. For severe cases, a doctor may prescribe drugs.

Night Terrors Versus Nightmares

Night terrors (known as pavor nocturnus in children) are relatively short nocturnal episodes during which the child sits up in bed, emits a piercing scream or cry, looks frightened, and sweats and breathes profusely. Episodes usually occur between the ages of 4 and 12, are more common in boys than girls, and can be expected to disappear as the child grows older. Typically, they occur during the first third of the night. The disorder may progress to sleep walking, but generally that only happens when the child is made to stand up. Later the child will forget the entire episode. Parents should comfort and provide warmth and support to children who experience night terrors. The condition does not indicate any personality disorder.

Nightmares, unlike night terrors, can be recalled afterward and are accompanied by much less anxiety and movement. These frightening dream experiences, which tend to occur at times of insecurity, emotional turmoil, depression, or guilt, can occur in all age groups. They are rarely accompanied by the anguished, terrified scream of the night-terror arousal. A person experiencing a nightmare will usually recount in de tail a threat which ultimately led to the awakening. Some people rarely have nightmares, while others seem predisposed to them.


Bedwetting (enuresis) is a common childhood sleep disorder which, contrary to popular belief,. is almost never emotionally or psychologically caused; less than 1 percent of bedwetting has an emotional source. About 5 to 17 percent of children aged 3 to 5 wet their beds; usually the condition will stop by the age of 4 or 5. However, a bedwetting child may feel guilty or ashamed. Waking the child up in the middle of the night or handing out punishments and rewards may only serve to increase the problem.

In most cases, the cause is unknown, but a congenitally small bladder, a bladder infection, or some other physical problem may be responsible. Bedwetting that continues into adolescence or adulthood may be attributed: to emotional problems, but neurological disease or diabetes also can be the cause. If the disorder persists, a physician should be consulted. For some children, drugs or time away from home may be prescribed for short periods, such as a week at camp or a weekend with friends or relatives.

Help for Sleep Disorders

If your sleep is continually disrupted and you lack initiative and energy during the day, you should seek professional help. In most cases of sleep disorder, it's best to see your own physician first, in order to sort out the general nature and severity of a sleep problem. The physician may conduct a thorough physical examination, ask you questions about your sleep habits and emotional state, and can often determine whether the sleep difficulty is related to treatable causes. However, if necessary, a referral to a mental health specialist or facility, a sleep clinic, or a sleep disorders center may be made.

The same basic service is provided by both sleep clinics and sleep disorders centers. Generally, sleep clinics are set up as part of hospitals. Sleep disorders centers may be associated with hospitals, medical centers, universities, or psychiatric or neurological institutes. Most clinics or centers primarily treat patients on referral from general practitioners and internists. However, it is possible to obtain information on specific sleep problems directly from a clinic or center or to make an appointment for a consultation.

Specialized sleep facilities usually have on their staffs experts called somnologists with training in a variety of medical and scientific fields. A sleep disorders team will often include a physician, a psychologist, a psychiatrist, and a surgeon.

Patients are typically seen as outpatients. They are interviewed thoroughly, given a battery of psychological tests and, if indicated, have their sleep patterns recorded in the laboratory for one night (sometimes two or three consecutive nights) to determine the cause of the sleep disturbance.

Fees vary, depending on the clinic or center. An entire analysis can range from a few hundred to about a thousand dollars. Insurance companies or Medicare, may cover some of the cost. (This can be determined by consulting the center or your insurance company.)

Special sleep facilities are scattered throughout the country. Your physician or nearest hospital should be able to help you locate the nearest sleep clinic or center. Or, for a complete roster of accredited and provisional sleep disorders centers and clinics, write to:

Association of Professional Sleep Societies
604 2nd St., SW Rochester, MN 55902

American Narcolepsy Association
P.O. Box 1187
San Carlos, CA 94070

Narcolepsy Network
155 Van Brackle Rd.
Aberdeen, NJ 07747

This information was written by science writer Gerald S. Synder, on contract with the Science Communication Branch, Office of Science Information, National Institute of Mental Health.