So when you're in REM sleep, your brain is very active, our body is quiet, but your brain is really processing a lot of things, a lot of emotions; we dream the most in REM sleep. And then you go back down in the deep stages, and so on and so forth.

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.

There's confusional arousals, there are states in deeper sleep that can happen where people will go and they'll disappear and they'll take on some other persona. They'll commit some crime, but it's all when they are in a very deep stage of sleep. So you really need to have a very thorough evaluation.

Well, the actual function of the brain, not so sure yet. There's a lot of different theories about it, but when you talk about psychologically in your brain, a lot of people with insomnia, though not all, report that they can't turn their minds off.

We'll work on relaxation strategies and also changing the times you go to bed will actually make them sleep a little bit less for a few nights so their body's natural sleep drive starts to kick in. That is very effective in about 60% to 70% of patients who do it, four to eight sessions, not even every week; it works for 60% to 70% of patients.

Nightmares are distinctly different from dreams in the way that people feel them and experience them. So a lot of people think that a nightmare is something where something is chasing them and you have to wake up screaming. Yes, that's one of the more common nightmares that we see is the person chasing someone or they're being chased.

There's a problem for them [teens] when they have to get up and go to school in the morning, they're very sleepy, yet on the weekends, they'll sleep 12 hours, they'll sleep late and then go to bed late and wake up late. And on vacations, it's not a problem.