We haven't really - it's harder for us to set those rhythms. So it's really important to keep a steady bedtime and wake time to really lock in those rhythms.

We haven't really - it's harder for us to set those rhythms. So it's really important to keep a steady bedtime and wake time to really lock in those rhythms.

So, sleep deprivation, and sometimes an insomnia, which is a little bit of a different form, but just getting a lack of sleep, can lead to a number of different decrements.

Narcolepsy is a disorder that affects many different areas of life. So in typical patients with narcolepsy, they have something called "excessive daytime sleepiness." So, they're very sleepy during the day. Yet, at night, they're still sleepy, but their sleep is very broken.

People went to bed when the sun went down and they woke up when the sun came up. That's what our bodies are naturally programmed to do. However, with all the new stresses in life with electricity, with technology, we tend to override that system and we'll stay up later and we'll get up earlier or later, and we use alarm clocks, we use the light.

There's some debate as to whether you need to awaken from them because there are some patients who are actually starting to say, "I had these horrible nightmares, but I never woke up from them." But they can still recall them when they get up in the morning. So there's still some debate in the field.

So we go through in the beginning of the night, we go into the really deep stages of sleep and we actually cycle through. So, when you go down to the deep stage, then you go back up and you actually come into something called REM sleep, which is after about 90 minutes.