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.

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.

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.

There are some patients who just have insomnia and they've had it since they were a kid and we don't quite know why. So when we look at the cause, we definitely want to treat whatever else is going on, but insomnia often because it becomes its own diagnosis and that requires its own treatment.

Night terrors are very different from nightmares. A lot of people will think they're the same, but they're really not. Night terrors - you want to look at the time of night when you're having the problem. Night Terrors happen in deep sleep. Nightmares tend to happen in a lighter REM sleep.

We try not using medications initially, and we use something called behavioral therapy for insomnia. This changes behaviors people do in bed, none of the tossing and turning.

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.