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.

It's uncommon, but there are some people who just have a delayed circadian rhythm and they just - they sleep better during the day then they do at night. So they've - a lot of those people with delayed sleep phase disorder they start to work in bars, they work some of the late night shifts, they sort of adjust to doing it more and more as time goes on.

We think is happening in the brain, the way I like to think about it is, it's almost like, you're brain is going through all these stages of sleep and it's developing in children so fast that it's almost like you're shifting gears in a car. And at some point, you actually stall out a little bit, and that's kind of what happens during a night terror.

People tend to remember their dreams in the morning a little bit better and if earlier in the night, when you're in a lot of deep sleep, if someone wakes you, or the phone rings or something, you're really confused.

So when it comes to circadian rhythms, it's a clock that's basically programmed in our body. So if you think back to times when people lived on farms and we didn't have electricity.

And you cycle throughout so that you do about five to six cycles throughout the night. And we spend more time in REM later on in the night than we do earlier on.

We try not using medications initially, and we use something called behavioral therapy for insomnia. This changes behaviors people do in bed, none of the tossing and turning.