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.

In general, there are patients with insomnia who - many patients with insomnia will actually over report the lack of sleep that they are getting.

Really if it's an hour or two after you've fallen asleep because you're in such a deep sleep at that point.

There's a new line of research showing that people who don't get enough sleep, they're body doesn't metabolize as well. And so they actually - it leads to weight gain. So if you're not getting enough sleep, you might have difficulty losing weight.

Some patients will report that they have sleep paralysis. If we see sleep paralysis alone and nothing else, we don't really think all that much of it, but if we see other symptoms, then it might be a red flag for something else that's going on.

Night terrors are very different from nightmares. A lot of people will think they're the same, but they're really not. Night terrors - you want to look at the time of night when you're having the problem. Night Terrors happen in deep sleep. Nightmares tend to happen in a lighter REM sleep.

So a lot of people who work rotating shifts and they work at night, their bodies are set to want to be awake during the day and sleep at night. So there are some people who have a lot of trouble adjusting their rhythms and they have trouble working the night shift, they're sleepy, they're drowsy driving home.