Sleep is a necessary part of life, a time in which brain and body repair and rejuvenation occurs. Different types of processes happen throughout the night during sleep, and are marked by changes in brainwave patterns that may be monitored.

A normal sleep cycle goes from light sleep into deep sleep and then back out to the lighter dreaming REM (rapid eye movement) sleep. Although REM sleep is universally thought to be when dreams occur, there is evidence that dreams may also occur during non-REM periods additionally.

Most people have about four of these cycles during an optimal seven to eight hour night's sleep.

Lack of sleep has these results:

1 night missed: fatigue, reduced attention span, loss of short term memory.

2-3 nights missed: poor coordination, muscle twitches, impaired judgment, blurred vision, nausea, microsleep (in which the body involuntarily falls asleep for a few seconds without the individual being conscious of it.

4-5 nights missed: extreme irritability, hallucinations, delusions

6-8 nights missed: psychotic-like behavior, paranoia

9+ nights missed: fragmented thinking (incomplete thinking/expression), unresponsive conscousness.

11 nights missed: death from a breakdown of bodily functions. (Rats die after 2 weeks without sleep).

The brain repairs itself during sleep and reverses the effects and damage from free radicals and normal metabolism.

Sleep may act like computer "defragmentation- during sleep, the brain takes information gathered during the day and sorts and catalogs it into useful skill and memory.

LEARNING

Creativity is the result of associations of memories made during rest:

• When a person is taught a new skill, his or her performance does not improve until he or she receives at least eight hours of sleep. AN extended period of sleep ensures that the brain will be able to complete the full sleep cycle, including REM sleep. The necessity of sleep for learning could be due to the fact that sleep increases the production of proteins while reducing the rate at which they are broken down. Proteins are used to regenerate the neurons within the brain. Without them, new synapses may not be able to be formed, thus limiting the amount of information a sleep-deprived individual can maintain.

• People taught a skill and then deprived of non-REM sleep could recall what they had learned after sleeping, while people deprived of REM sleep could not. We typically spend more than 2 hours each night dreaming. The REM period of sleep seems to be crucial for reorganizing experiences into useful skill and memory.

• In one study, there were two groups of individuals who trained for a new keyboard skill and were tested on it 12 hours later. One group trained at 10 AM and was tested at 10 PM. The other group trained at 10 PM and was tested the next morning at 10 AM, after sleep.  The group that slept scored significantly higher in skill.

The TEMPORAL LOBES are inactive after sleep deprivation, showing problems with processing language which is processed in this left side of the brain.

The FRONTAL LOBES show lack of creative syntheses and ideation after lack of sleep. However, after a SHORT NAP, the frontal lobes and pre-frontal cortex are refreshed. It is well known that a short nap will reveal a creative solution. Thomas Edison is well known for taking advantage of this, using his cat naps to help find a solution to a stubborn problem.

The IMMUNE SYSTEM is weakened without sleep. One study stated that people who sleep less than four hours per night are three times more likely to die within the next six years. Although the longest a human has remained awake was eleven days, rats that are continually deprived of sleep die withing two to five weeks, generally due to their severely weakened immune system.

LUCID DREAMING

As a rule, the pre-frontal cortex remains largely inactive during dreaming. In dreaming we likewise think little about the future, simply going along with the dream narrative without question. In this vein there seems a significant attenuation of attention during dream as well as a loss of self-reflection.

In waking life the prefrontal lobe plays an important role in maintaining a sense of self-identity, and particularly an ability for self-reflection. With these abilities "off-line" during dreaming, the dreamer has little ability to reflect on the situation, or even notice the strangeness of events experienced in the dream state.

On the other hand, people who LUCID DREAM show a signature spike in frontal lobes brain waves, and appear to experience a dream with continuing the activation of the frontal lobes. The lucid dream seems to be a world "between two worlds", that of the pure dream and that of waking reality.

It appears that lucid dreaming is a bridge between the imagination/memory of the dream state and the insight and conscious rational processes available to the frontal lobes.

Lucid dream is a skill that can be learned to a certain extent, provided there is a conscious and willing effort to do so. To encourage a conscious lucid dream one may a) Keep a dream journal b) stay in bed after waking up and reviewing the previous dream, then falling back to sleep c) Taking a nap only a couple of hours after waking in the morning, or early in the day.

THE AMYGDALA and SLEEP

Depression is associated with disordered rapid eye movement REM sleep. The amygdala contains neurons that project into the brainstem as well as other major parts of the brain, and it appears to be involved in modulating REM sleep. Investigators from the Sleep and Neuroimaging Laboratory, University of California, Berkeley, presented evidence consistent with the claim the REM sleep functions in part to facilitate emotional regulation. This means that normal reactive processes of the amygdala (fear and negative response in this experiment) are "depotentiated" and defuse. I.e., the same negative stimulus loses its ability to cause a negative reaction after sleep.

The experiment was as follows- a subject was shown an image that caused an negative amygdala reaction. Either the person stayed awake for 12 hours, or was allowed to sleep. The image was re-shown again, to either produce a similar negative reaction, or show a decreased defused non-reaction. The experiment demonstrated-

• Those who slept between the image viewings reported a significant decrease in their ratings of the intensity of the emotional images as well as a decreased in amygdala reactivity while the participants who were awake between viewings/ratings demonstrated increases in both ratings and amygdala reactivity.

BENEFITS of ENOUGH SLEEP

Weight loss: Lack of sleep causes a decrease in plasma leptin and an increase in gherlin levels. Leptin curbs one's appetite, and ghrelin gives you an appetite. Sleep keeps these substances at a normal level.

Cancer Preventative: Sleeping too much or too little increases your chances of dying from all causes by up to 15 % according to some studies. People who get enough sleep show lower levels of cancer.

Growth Hormone is released during sleep from your pituitary gland, even for adults. This strengthens your bones, increases muscle mass, helps you lose body fat, increases protein synthesis for healthy internal organs.

Sleep stimulates your immune system and supports your pancreas' ability to make insulin.

GET ENOUGH SLEEP

Here are some tips that will help you sleep better and get enough sleep:

Remind yourself the reasons for getting enough sleep- so you do!

Teenagers, due to hormone changes, tend to sleep two hours later at night than adults, and tend to rise two hours later. Don't be alarmed, and understand this natural tendency and difference.

Go to bed at roughly the same time each night.

Before you sleep, visualize how you would like the next day to be. Ask yourself a question that you want answered why you sleep and expect to know the answer upon awakening, spontaneously revealed, or revealed in your dream.

Keep  your bed and bedroom attractive and pleasant, and free from unnecessary clutter.

Keep lights off until morning, even if you have to use the bathroom. This will allow melatonin (sleep brain chemical) to continue.

Use a white noise or relaxation machine or CD to help fall asleep.

Keep earplugs or a sleep mask near your bed and use if helpful to keep out distractions.

Watch what you eat immediately and some time before bed, and keep notes what may cause problems.

Generally, alcohol, high protein, and high sugar foods will disturb sleep. Consider a high complex carbohydrate with a small amount of protein to be a sleep inducing snack. This makes tryptophan available to the brain and promotes sleep.

Socks may help you to stay warm and comfortable in bed.

Avoid large amounts of liquids before bed so you don't have to go the the bathroom often in the middle of the night.

A hot bath or shower can relax you.

Lavender oil dropped on your pillow or bed is a soothing and relaxing scent.