Biology 202
2003 Second Web Paper
On Serendip

Sleepiness, whether due to sleep apnea, heavy snoring, idiopathic hypersomnolence, narcolepsy or insomnia from any number of sleep-related disorders, threatens millions of Americans' health and economic security (1). Perhaps somewhat most concerning of these disorders are those that allow sleep without having any control over when it happens-idiopathic hypersomnolence and narcolepsy. The two are closely related in that both cause individuals to fall asleep without such control, yet narcolepsy occurs without any dreaming during naps (2). For years, narcoleptic people have been falling asleep in corners, concerned, as they have given numerous attempts to try to stay focused and awake. But besides the excessive fatigue that people experience, there surely must be more that can be associated with causing such sleepiness among people at an uncontrolled level. There might especially not be a reason involving the I-function of the brain, as people are not aware of when necessarily they will fall into their deep sleep.

Narcolepsy has been clinically defined as a chronic neurological disorder that involves the body's central nervous system (CNS). The CNS is basically like a "highway" of nerves that carries messages from the brain to other parts of the body. Thus, for people with narcolepsy, the messages about when to sleep and when to be awake sometimes hit roadblocks or detours and arrive in the wrong place at the wrong time. This is why someone who has narcolepsy, not managed by medications, may fall asleep while eating dinner or engaged in social activities-or even at times when they are so focused on being awake, yet they cannot be due to their narcoleptic nature.

In many cases, however, diagnosis is not made until many years after the onset of symptoms. Studies on the epidemiology of narcolepsy show an incidence of 0.2 to 1.6 per thousand in European countries, Japan and the United States, a frequency at least as large as that of Multiple Sclerosis (3). This is probably due to the fact that patients only go to see a physician after many years of excessive sleepiness, rather than trying to approach it right away, assuming that sleepiness is not indicative of any kind of disease. Most people actually probably assume that their need to sleep is due to something that can be easily controlled by changing one's daily routines and/or lifestyle, which with such reasoning would easily delay any visits to a physician.

Assumptions aside, recent discoveries indicate that people with narcolepsy lack a chemical in the brain called hypocretin, which normally stimulates arousal and helps regulate sleep. They also discovered that there is a reduction in the number of Hcrt cells or neurons that secrete hypocretin (4). What this is due to is still rather uncertain. It is obvious that some degenerative process occurs which would lower the number of cells/neurons that can secrete this stimulating substance. However, it might also be an immune response to something else occurring in the body. For example, the amount of seratonin in the body may also have something to do with sleep response. During REM sleep, your brain produces a vital chemical called Seratonin (5). Seratonin is a neurotransmitter, involved in the transmission of nerve impulses. Your body uses Seratonin every day and lack of REM sleep means you are producing less or none at all. The substance that processes this neurotransmitter is the amino acid tryptophan. In the brain, it increases the amount of seratonin, which cause one to have better feeling of their well-being. Seratonin is a chemical that helps maintain a "happy feeling," and seems to help keep our moods under control by helping with sleep, calming anxiety, and relieving depression (6). Thus, if there is not enough seratonin produced, mood can be affected as can the ability to sleep. Among other possible factors, these hopefully can account for some of the visible symptoms we can actually see, or in the lapses in neurological pathways, that we cannot see.

Among the symptoms usually observed, excessive daytime sleepiness is usually the first noted. This is probably the most overwhelming and troubling symptom as people who want to stay awake during the day encounter this problem. The "I-function", a link between body and mind, which seems to be in control of conscious actions, does not seem to play a part in narcolepsy. Instead, it seems that it is forced to sit back because of the lapse in neurological connections. We can see this in that in a narcoleptic person, the "I-function" has been affected and thus cannot help regulate sleep under a conscious individual's scope of regular control over their body. This may lead to what is perceived to be as little sleep, as a person may be frustrated and tiring themselves out trying to keep themselves awake. While someone who is narcoleptic may get more sleep than most, they still feel exhausted and sleepy. Also, at times a narcoleptic may also experience sudden excitement or be taken off guard, in which case their muscles may become weak, leading them to collapse and fall asleep-another symptom of narcolepsy known as cataplexy. So in essence, the narcoleptic, on a regular basis listens to its body as to when it goes to sleep without even consulting the "I-function" which results in frustration as people have become accustomed to being in control of such an integral part of their daily lives.

Narcolepsy is also determined through other symptoms like sleep paralysis, hypnagogic hallucinations and automatic behavior. Sleep paralysis is being unable to talk or move for a brief period when falling asleep or waking up. Many people with narcolepsy will suffer short-lasting partial or complete sleep paralysis. Hypnagogic hallucinations are vivid, scary dreams and sounds reported when falling asleep. And automatic behavior, on the other hand, is the habit of carrying out routine tasks but without full awareness or memory of them later (4). These symptoms often aid in a physician's diagnosis of narcolepsy. However, as they are often associated with other disorders, it becomes increasingly difficult to differentiate what constitutes a symptom of narcolepsy compared to the effects seen from some other disorder. There are, on the other hand, polysomnogram tests available that would measure brain waves and body movements as well as nerve and muscle function (4). This is a big leap in helping diagnose narcolepsy, yet it is an option many people might not be able to take on, for whichever reason, be it economically or for possible inconclusive results nonetheless.

There are many treatments currently available to victims of the sleepy disorder. There is currently no permanent cure for narcolepsy, however, the options available help deal with it in a fitting manner. Stimulants are the mainstay of drug therapy for excessive daytime sleepiness and sleep attacks in narcolepsy patients. These include methylphenidate (Ritalin), modafinil, dextroamphetamine, and pemoline. Dosages of these medications are determined on a case-by-case basis, and they are generally taken in the morning and at noon. Other drugs, such as certain antidepressants and drugs that are still being tested in the United States, are also used to treat the predominant symptoms of narcolepsy (7). On the other hand, drug treatment is only one element of dealing with the symptoms of narcolepsy.

Changes in daily behavior can also help to encourage nighttime sleeping. Avoiding caffeine, nicotine and alcohol in the late afternoon or evening, as well as exercising regularly-at least three hours before bedtime are easy things to incorporate into one's lifestyle to help get more sleep in. Eating foods that are high in tryptophan promotes sleep (8). Great examples of this can be found in turkey, milk, bananas and yogurt. Making sure to get enough nighttime sleep in, at least eight hours could help with this, just as taking regular naps that last between 20-40 minutes at a time. These power naps can really help boost one's energy to alleviate the stress of not getting enough rest in one's day.

So the question remains: What really causes narcolepsy? Yes, we already know that it is a chronic neurological disorder that involves the CNS. But what it is that accounts for this lapse in pathway? While much research has been done, it still remains a difficult task to be able to diagnose narcolepsy, as many of the symptoms are often associated with other more credible disorders, at least in the eyes of those avoiding physicians. Many options are available to try to control this disorder. What we have seen to regularly play a huge role in controlling the body-the "I-function", is being forced to stand aside while the body dictates its irregular sleeping pattern. The intricacies of narcolepsy remain something to be further investigated to find a means to diagnose it properly, preferably earlier on, and to treat it so that this disorder can one day not bring about further economic or personal grief.

References

1)Sleep Apnea, Snoring, Narcolepsy, Insomnia and Other Causes of Daytime Fatigue

2)Better Sleep Now!

3)Center for Narcolepsy: Symptoms and Diagnosis

4)Living With Narcolepsy

5)Sleepnet.com Apnea Forum

6)Seratonin: The chemistry of Well-Being

7)Sleep Channel: Narcolepsy

8)Sleep: Alternative and Integral Therapies


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