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.

When it comes to the reason why we have nightmares, we're still debating that. It's a new area of research, nightmares. And the way I like to think about it is, our brain - we have stress during the day and our brain needs to learn to process this stress.

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.

Decrements in attention and concentration, being able to learn more efficiently, that's just not as good. Also, there are motor vehicle accidents, workplace accidents, we see that a lot.

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

There are some people who believe that dreams really are just kind of a throwaway thing. They are just a way of your brain processing what's happening during the day, but there's really no meaning to them; a lot of imagery of just flashes of what happened.

If there's a lot of fear that's going on, if there's a lot of anxiety, it's manifesting itself in your nocturnal world so that analyzing it can help open up basically thoughts about what you need to do during the day. So a lot of people who subscribe to the psychoanalysis, the Jungian thought will really focus a lot on dreams, the meaning, and how it can be used to help you during the day.