Dr. Jerome Siegel: What we don't know about sleep is exactly what long term deficiencies result from sleep loss if any.

Male Speaker: We need it to survive just like air, food and water. Sleep is something every living creature does, yet often, with our busy lifestyles, people shortchange sleep. Why is that a problem? What really goes on behind closed eyes? The face of a sleeping baby.

Dr. Jerome Siegel: Children are very good sleepers and they can sleep pretty well despite a lot of circumstances.

Male Speaker: Busy adults might not think too much about sleep except that it comes at the end of a frenzy day. But sleep is important, so important we spend one-thirds of our lives doing it.

Dr. Jerome Siegel: If you don't have continuous sleep, it is not restorative, it is not restful.

Male Speaker: Lack of sleep causes inattentiveness and learning difficulties, but there is a bigger question.

Dr. Jerome Siegel: If you don't get sleep, will it shorten your lifespan?

Male Speaker: Jerome Siegel has studied sleep for 30 years.

Dr. Jerome Siegel: Under extreme conditions, in animals, if they are totally sleep deprived for periods of weeks, they will die. They will die sooner than if they don't get food.

Male Speaker: During sleep, heart rate, blood pressure and temperature drop. The body also secretes growth hormones that regulate body mass and appetite.

Dr. Esra Tasali: Sleep deprivation has significant detrimental effects on our metabolism, on our endocrine function and especially on our carbohydrate metabolism. This will, again, measure your eye movements during your sleep.

Male Speaker: A recent study shows when healthy volunteers are sleep deprived, they become pre-diabetic in just one week. Lack of sleep also creates problems for dieters.

Dr. Esra Tasali: The appetite hormone Ghrelin goes up which again signals the brain that you have to have more food.

Male Speaker: So how much sleep do you get?

Female Speaker: Probably 5 or 6 hours.

Female Speaker: 7-8 hours a night.

Male Speaker: 9 hours roughly.

Dr. Jerome Siegel: Contrary to what most people have been taught, 8 hours of sleep is not the optimal.

Male Speaker: One study shows people who slept seven hours a night, were more likely to be alive five years later than those who slept six and those who slept eight hours a night. The greatest mystery of sleep maybe what happens in our dreams.

Michael Walver: I saw I was being chased by this barbarian figure down a street and he was throwing axes at me.

Keelin: I reached forward and I started to sort of dig into the face and it broke apart as if it were made of wet clay.

Male Speaker: Adults spend at least one quarter of their sleep time in rapid eye movement also called REM or Dream Sleep.

Jeremy Taylor: All dreams, even the nastiest nightmares, come ultimately in the service of Health and Wholeness.

Stephen LaBerge: Public self-consciousness more likely in dreams than waking.

Male Speaker: In groups like this, people share dream experiences hoping to find a deeper meaning. Keelin says dreams help her feel close to her father, who died when she was just 11.

Keelin: Dreams became a way for me to feel that connection.

Male Speaker: Many adults have difficulty remembering dreams. Immediately documenting a dream's detail can help, while certain drugs like anti-depressant hinder recall. Even more interesting is something called lucid dreaming.

Stephen LaBerge: Lucid Dreaming just means, dreaming while knowing that you are dreaming at the time.

Male Speaker: This mask is designed to alert sleepers when they have hit dreams phase.

Stephen LaBerge: People like to have lucid dreams primarily because they are fun; they are an exhilarating experience of freedom.

Male Speaker: Sensors detect rapid eye moment, while still asleep participants learn to direct their dreams to help them work through real life problems like depression and anxiety.

Stephen LaBerge: It seems there must be a greater benefit to dream and that can be attainted by knowing what to make of it. So I think it is one of those areas of life that is a potential, waiting to be discovered.

Male Speaker: As we age, biological factors cause our sleep to become lighter and more restless. If that's the case for you, it is a good idea to check with your doctor to see if another medical issue can be causing the problem.