We've looked at sleep diaries of patients with insomnia, and they'll say that they don't sleep for one or two days. And the body actually has a natural function, after about the third day to start catching up and you get a little bit more sleep the third night. And that's usually what I tell my patients.

So someone who is a child usually goes to bed about 8:00 or 9:00 at night, but then when they have a circadian rhythm shift, it shifts later. And this is natural. And they start to go to bed at 11:00, 12:00, 1:00 and they want to sleep later. So we see this a lot in teens.

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.

We have other opposite problems with circadian rhythms that can happen when you - a lot of times with older adults. They start to go to bed at 6:00, 7:00 at night and they wake up at 2:00 in the morning. And they're rhythms actually shift earlier, but sometime it can just kind of miss the mark and shift too much earlier and that's when we need to treat it with bright light.

Honestly, what we use a lot is melatonin. So we use lower dosages of melatonin, taking it at different times, depending upon where we are traveling and that can really help adjust the body's rhythm to wherever you are going.

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.

Night terrors are in deep sleep, and they're more common in kids, as are nightmares, but what happens in a night terror is like a flash - we think a flash of some image or something happens in the brain. We don't really quite know what. And it usually ends up with the child screaming almost like screaming bloody murder. It's very scary for the parents or whoever else is around.