What is Sleep|Sleeping.

Sleep or sleeping has been defined in many ways which basically all mean the same. This is what definition of  sleep means.

• Natural periodic (usually nocturnal) state of rest of body and mind in which the eyes are closed and wakefulness is not present.
• Temporary suspension of consciousness and volition (act of making a conscious choice or decision).
• Behavioral state in which voluntary body functions are partially suspended
• Characteristic immobile body posture.
• Diminished sensitivity to external stimuli which is reversible.

Sleeping like a baby.

What Happens During Sleep|Physiology of Sleep.

Sleep is present in all mammals, all birds, most reptiles, fish and amphibians, and forms an essential part of living.  William Shakespeare described it best when he called sleep “nature’s soft nurse”. Considering the fact that on an average we spend 25 years of our life sleeping (that is 1/3^rd of our life), sleep is still a subject of intense research and scientists are still trying to figure out the complete benefits and mechanism of sleep. Though EEG (electroencephalogram) records the brainwaves, scientists still cannot say what the brain exactly does during sleep besides producing dreams.

Though sleep is the absence of wakefulness, many areas in the brain are active during sleep. It is the brain which is responsible for generating sleep. When you are asleep, the body and mind do not sleep but both are active, performing their various functions such correcting chemical imbalances, maintaining sugar levels, sharpening memory and a lots more.

Importance of Sleep.

As mentioned above, sleep is essential for all animals and is a complex process by which not only the mind but the body too, is restored, renewed and rejuvenated. The importance of sleep can be gauged from the fact that many diseases are caused as a result of sleeping disorders. Lack of sleep not only causes mental insufficiency but also physical inadequacy.

Deprivation of sleep causes reduced energy levels, lack of concentration, a depressed mood, and reduced overall efficiency. Long periods of sleep deprivation has resulted is in stress related deaths in lab animals, which could even happen to humans.

Functions of Sleep.

• Sleep slows down metabolism thereby saving and restoring energy.
• During sleep, most neurons of the brain decrease their activity thereby helping to replenish stores of neurotransmitters (chemical inter-neuron messengers in the brain) which are responsible for the mood sentiment.
• During sleep, the brain gets rest  which helps it to restore itself.
• During sleep  the neurons that are involved with learning and memory rest and therefore we are mentally sharper and more attentive during the next day with a good night’s sleep compared to otherwise. Working memory (ability to actively store information in the mind), which is important for high level cognitive functions has been shown to be affected by lack of proper sleep.
• Sleep helps to keep your immune system healthy. Deprivation of sleep has been shown to adversely affect the immune system causing delayed healing of wounds.
• Sleep is necessary for our nervous system to work properly.
• Deep sleep is associated with the release of growth hormones in children and young adults. Body cells show increased activity and reduced break down of proteins  which helps in cell growth and repair of damage caused by stress and other external factors.

Sleep Debt|Sleep Deficit.

Sleep debt is the cumulative effect on the body of not getting enough sleep. A large sleep deficit can cause physical, emotional and mental fatigue. High level cognitive functions are also diminished. However, how much of sleep debt can be accumulated by a human is still to be established.

Related posts:

1. NREM Sleep – Non Rapid Eye Movement Sleep.
2. Managing Stress and Relaxation Techniques to Sleep Well.
3. Sleep Aids To Help You Sleep.
4. How Much Sleep Do You Need.
5. How To Get Sleep.
6. Proper Bedroom and Bed to Sleep Better.
7. Over The Counter and Natural Sleep Aids to Help You Sleep.
8. REM Sleep – The Dreamer’s Sleep.