How does narcolepsy start

The loss of hypocretin-producing neurons in the hypothalamus is the primary cause of type 1 narcolepsy. These neurons are important for stabilizing sleep and wake states. This results in the sleep fragmentation and daytime symptoms that people with narcolepsy experience.

It remains unclear exactly why hypocretin neurons die. However, research increasingly points to immune system abnormalities. HLA—human leukocyte antigen—genes play an important role in regulating the immune system.

Most people with narcolepsy have this gene variation and may also have specific versions of closely related HLA genes. This indicates that other genetic and environmental factors are important in determining if an individual will develop the disorder.

Narcolepsy follows a seasonal pattern and is more likely to develop in the spring and early summer after the winter season, a time when people are more likely to get sick.

By studying people soon after they develop the disorder, scientists have discovered that individuals with narcolepsy have high levels of anti-streptolysin O antibodies, indicating an immune response to a recent bacterial infection such as strep throat.

Also, the H1N1 influenza epidemic in resulted in a large increase in the number of new cases of narcolepsy. The mission of the National Institute of Neurological Disorders and Stroke NINDS is to seek fundamental knowledge about the brain and nervous system and to use that knowledge to reduce the burden of neurological disease.

Genetics and biochemicals NINDS-sponsored researchers are conducting studies devoted to further clarifying the wide range of genetic —both HLA genes and non-HLA genes—and environmental factors that may cause narcolepsy. Other investigators are using animal models to better understand hypocretin and other chemicals such as glutamate that may play a key role in regulating sleep and wakefulness. Researchers are also investigating wake-promoting compounds to widen the range of available therapeutic options and create treatment options that reduce undesired side effects and decrease the potential for abuse.

A greater understanding of the complex genetic and biochemical bases of narcolepsy will eventually lead to new therapies to control symptoms and may lead to a cure. Immune system Abnormalities in the immune system may play an important role in the development of narcolepsy. NINDS-sponsored scientists have demonstrated the presence of unusual immune system activity in people with narcolepsy. Further, strep throat and certain varieties of influenza are now thought to be triggers in some at-risk individuals.

Other NINDS researchers are also working to understand why the immune system destroys hypocretin neurons in narcolepsy in the hopes of finding a way to prevent or cure the disorder. Sleep biology The NINDS continues to support investigations into the basic biology of sleep, such as examining the brain mechanisms involved in generating and regulating REM sleep and other sleep behaviors.

Since sleep and circadian rhythms are controlled by networks of neurons in the brain, NINDS researchers are also examining how neuronal circuits function in the body and contribute to sleep disorders like narcolepsy. A more comprehensive understanding of the complex biology of sleep will give scientists a better understanding of the processes that underlie narcolepsy and other sleep disorders.

The NINDS supports the NIH NeuroBioBank , a national resource for investigators using human post-mortem brain tissue and related biospecimens for their research to understand conditions of the nervous system.

To learn more about types of sleep and sleep cycles, see Healthy Sleep. In people with narcolepsy, the regulation of sleep is disrupted: the boundaries between wakefulness and sleep are less distinct, and elements of sleep and wakefulness can mix together. The sleep patterns of people with narcolepsy differ in several ways from the sleep patterns of people who do not have the disorder:. Narcolepsy What Is Narcolepsy?

Share Email Digg Facebook Delicious. Narcolepsy is a neurologic disorder and is one of the most common causes of chronic sleepiness. The total time someone with narcolepsy spends sleeping is not necessarily different from that of people who do not have the condition. During REM sleep, your brain activity increases and you may dream. During the latter part of the night, REM sleep is more prominent.

If you have narcolepsy, this pattern is much more fragmented and you may wake several times during the night. You may also experience REM sleep much earlier than normal after falling asleep, and the effects of REM sleep, such as dreaming and paralysis, while you're still conscious. Narcolepsy can sometimes be the result of an underlying condition that damages the areas of the brain that produce hypocretin. Page last reviewed: 13 May Next review due: 13 May EDS makes it difficult to function properly during the day.

Cataplexy is a sudden, temporary loss of muscle tone. It can range from drooping eyelids referred to as partial cataplexy to total body collapse. Laughing and intense emotions, such as excitement and fear, can trigger cataplexy. How often it occurs varies from person to person. It can happen several times per day to once a year. Sometimes cataplexy may occur later in the disease course, or it may not be known if you take medications that suppress it, such as certain antidepressants.

REM sleep is the sleep stage when you have vivid dreams with loss of muscle tone. It usually starts about 90 minutes after you fall asleep. REM sleep can happen at any time of day for people with narcolepsy, within about 15 minutes after falling asleep. Sleep paralysis is an inability to move or speak while falling asleep, sleeping, or waking.

Episodes last only a few seconds or minutes. Sleep paralysis mimics the paralysis seen during REM sleep. People with narcolepsy may have vivid hallucinations at the same time as sleep paralysis. The hallucinations usually occur when falling asleep or waking up. Although people with narcolepsy are excessively sleepy during the daytime, they may have difficulty falling asleep at night.

Narcolepsy is a chronic condition. Medications, lifestyle adjustments, and avoiding hazardous activities can all play a part in managing this condition.