Sleep is one of the body's most mysterious processes.

Humans have a biological clock known as the Circadian Rhythm.

It repeats every 24 hours. Cycle of sleep and wakefulnessAnything that throws off your

biological clock can affect how you feel and behave. Jet lag for example can cause

fatigue, sleepiness and temporary cognitive deficits.

Memory and learning – Sleep seems to organize memories, as well as help you to recover memories. After you learn something new, sleep may solidify the learning in your brain.

Mood enhancement and social behaviors - The parts of the brain that control emotions, decision-making, and social interactions slow down dramatically during sleep, allowing optimal performance when awake. REM sleep seems especially important for a good mood during the day. Tired people are often cranky and easily frustrated.

Nervous system – Some sleep experts suggest that neurons used during the day repair themselves during sleep. When we experience sleep deprivation, neurons are unable to perform effectively, and the nervous system is impaired.

Immune system – Without adequate sleep, the immune system becomes weak, and the body becomes more vulnerable to infection and disease.

Growth and development – Growth hormones are released during sleep, and sleep is vital to proper physical and mental development.

Reduced response to stimulation, such as sounds and touch.

Slowed-down metabolismComplex and active brain patterns.

Sleep is divided into two types: REM (Rapid Eye Movement) NREM (non-REM). REM Sleep is when we dream. NREM is further divided into four stages.

When you first fall asleep, you are in Stage 1 sleep.

Five to ten minutes. Eyes move slowly under the

eyelids, and muscle activity slows down.

You are easily awakened during Stage 1.

Next, you go into Stage 2 sleep. Eye movement stops, heart rate slows, and

body temperature decreases.

Then you enter Stages 3 & 4.

During these stages you are difficult to awaken.

People who immediately awaken during these stages often feel groggy and disoriented.

Children may experience bedwetting, night terrors and sleep walking during deep sleep.

At about 70-90 minutes into your sleep cycle, you enter REM sleep.

You usually have three to five REM episodes per night

Your eyes jerk rapidly in various directions under your eyelids, hence the name Rapid Eye Movement sleep.

Most vivid dreams in this stage.

Insomnia is the inability to sleep. The most common type of insomnia is

when people have difficulty falling asleep. People with insomnia are more likely to

have “racing minds” before bedtime. You can actually make insomnia worse by

trying to force yourself to fall asleep.

Psychologists urge insomniacs to stay clear of sleeping pills as these can become addictive.

They suggest you establish a regular bedtime, use pleasant images to help you relax, avoid worrying at bedtime (easier said than done), and try muscle relaxation techniques.

A nightmare you remember, a night terror you cannot remember.

Nightmares are fairly common, they say you experience, on average, about one a month.

Night terrors are common in young children, possibly due to immaturity in the nervous system.

With night terrors, you can feel your heart racing and you may suddenly awaken gasping for air, they also tend to occur in deep sleep, not REM.

This is common in children.Occurs during deep sleep.People tend to respond to

questions while they are up and about.

Contrary to popular belief, if you awaken a sleep walker they will not become violent or have a heart attack and die.

Also may reflect immaturity in the nervous system.

Breathing interruption that occurs during sleep.

Occurs when a persons air passages are blocked. Thus, they are sometimes accompanied by snoring.

A nasal mask that provides steady air flow can help treat this problem.

Many link SIDS (Sudden Infant Death Syndrome) to sleep apnea.

Rare sleep problem in which people fall asleep suddenly no matter what time it is or where they are. One minute they are awake. The next they are in REM sleep and their muscles are completely relaxed.

Drug therapy and frequent naps have been used to treat narcolepsy.

Believed to be a genetic disorder of REM-sleep functioning.

Yes, Laboratory studies have shown that we experience our most vivid dreams during REM sleep. REM sleep occurs every 90-100 minutes, 3 to 4 times a night.

There is something about the phenomenon of sleep itself which makes it difficult to remember what has occurred and most dreams are forgotten. Many people do, however, remember their dreams suggesting that memory is not totally lost but can be difficult to retrieve. Drugs and medication can also play a role.

Before you fall asleep, tell yourself you want to remember your dreams. Keep a notebook by your bedside. As you awaken try to move as little as possible and not think about your day right away. Jot down all images and dreams that come to mind before the memories quickly fade away.

Freudian View“ A dream is a wish

your heart makes”Freud believed that a

dream is the key to your subconscious urges.

Believed people dream in symbols that help them understand their desires they might not otherwise deal with consciously.

Biopsychological ViewBiological activity, not

psychological. Random neurons fire

in a part of the brain that controls movement and vision.

Neuron bursts are random and the brain tries to make sense of them, hence the dream.

Nightmares are fairly common in children and adults. Often they are caused by stress, traumatic experiences, emotional difficulties, or drugs and medication.

You often can influence your dreams by giving yourself pre-sleep suggestions. Another method of influencing dreams is called lucid dreaming, in which you are aware you are dreaming while asleep. Some psychologists, however, question the idea of actually controlling your dreams.

Relaxation is a must.Complete darkness, proper temperature,

and no distractions. Consistency, you are never to old for a

bedtime. Try not to eat or drink at least two hours

before bedtime. Plan on waking up slowly and peacefully.Health is very important. Poor nutrition is a

common cause of sleep difficulty.