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.

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.

So people only focus on getting the really deep sleep, but in reality, we spend almost 60% of the night in the stage two sleep.

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 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 are some that are - REM Behavior Disorder, we'll see some court documented cases. And they really need to have a thorough evaluation with a sleep specialist.