Now narcolepsy is really hard though because they're very tired during the day, they're sleepy during the day and it's managed mostly with medications. So we use medications to help them sleep better at night and to stay away during the day. But there are behavioral things you can do also by changing diet, exercise, having an actual nap schedule.

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

So the older models, when you look at Freudian, when you look at Jungian thought, and there's still people who really - who really use the Jungian thought of dream analysis, is really that you would analyze the dreams. The dreams are there for a purpose.

So, more times than not, but not every time, it can be linked to a medical problem, such as menopause, cancer, chronic pain, it can be linked to anxiety and depression. Those are the more common causes.

So you have it, you awaken from it and you can recall, in detail, what just happened, that's a nightmare. So it's very different from a dream where you generally don't wake up from it and you don't have this dysphoric emotion.

For some people they say, it's about wish fulfillment, it's about the things you are never able to do in your day you are actually fulfilling at night. There are other people who will say that it's actually telling you something.

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.