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.

Some patients will report that they have sleep paralysis. If we see sleep paralysis alone and nothing else, we don't really think all that much of it, but if we see other symptoms, then it might be a red flag for something else that's going on.

So the deeper stages of sleep are really those times of quiescence, you're really restoring your body and we have a few different stages of sleep.

When they [people with insomnia] start worrying about not sleeping, I'll say, "Say the mantra to myself; if I don't sleep tonight, I'll likely sleep tomorrow, and if not tomorrow then definitely the third" because our body has a way of naturally catching up.

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.

So it's like your brain has a large filing cabinet and it's opening up each drawer and it's taking in various images and memories from the day, consolidating what it needs to and puts in whatever file. And then if there's something that doesn't fit in any of the files and doesn't really belong, you'll forget about it. So it's a way of really getting a succinct way of storing things in your brain.

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.