NARRATOR : Virtually every culture has tried to decipher hidden meanings in dreams. You know. Like the one where we're falling?
DEIRDRE BARRETT (MD, Author "Committee of sleep") : Commonly for most people falling is a metaphor for losing face. Losing rank or in some way the physical world not being safe.
NARRATOR : Sounds good. How about the one where we're being chased?
DEIRDRE BARRETT : Generally in interpreting that sort of dream asking one's self: What do I not want to catch up to me? Or just what in waking life gives me the feeling of dread and panic that that dream of being chased does is going to tell you the most about what it means for you.
NARRATOR : All right. I'm almost too embarrassed to ask. What about the one where we forgot to put our clothes on?
DEIRDRE BARRETT : All of these dreams seem to be some representation of other shame issues for us. As a child learning to keep our bodies clothed is something that we're. We're taught and shamed about if we don't do it so it becomes an example for many other sort of waking situations in which feeling inadequate or like we haven't done the proper thing or feeling ashamed of something comes into play.
NARRATOR : All together we dream for roughly 25 percent of our total sleep time. It happens after we transition from light sleep to deep sleep to dream sleep. Characterized by rapid eye movement. Our brain is incredibly active at this stage but our bodies become paralyzed. Probably to prevent us from acting out our dreams. The latest research indicates that dreaming is essential for memory formation. Learn a task one day and after a good night of dreaming you'll perform it better the next day and dreaming may even be natural psychotherapy. Go to sleep after an unpleasant day and you'll wake up in a better mood.
Why we sleep has been one of science's biggest mysteries
Perhaps part of the answer is that we sleep to get the benefits of dreaming. Over the last 24 hours I've stayed up to learn first hand about sleep deprivation. But I've been using the time wisely. We've learned about our biological clocks and our daily body rhythms. We've gathered tips on getting to sleep and how to deal with jet lag and night shifts.
We've peered into the world of dreams and we've seen what happens when people get stuck in that strange space between being awake and being asleep.
KAT CARNEY : Okay. So I've been up for 24 hours. I'm quite tired and I'm now about to take my second driving test. Let's see how I do.
NARRATOR : As I drive. They're going to measure my speed, my steering and my reaction time once again. This test was pretty easy the first time. But now I'm having incredible difficulty concentrating on the road. Be honest. I can barely keep my eyes open. I can feel myself starting to speed and the steering wheel seems to have a mind of its own. I'm glad this is just a test.
KAT CARNEY : Oh. Thank goodness. Well. I didn't crash. But I don't think I need a scientist to tell me how I did. Not very good.
MARTIN MOORE-EDE : It was a short test but certainly it started to show the deteriorations we expect. And of course. You know. You don't get in too much trouble in ten minutes but if you're out there driving on the highway and you're really fatigued in an hour or so you can get into serious trouble.
KAT CARNEY : I hope you've enjoyed this journey inside the world of sleep. Scientists continue to ponder the future of sleep. And some even speculate that science may eventually eliminate the need for sleep at all. But if you ask me about the future of sleep? Well. All I have to say is it's time for this Kat to take a nap. Can someone please shut the door? Good night.