A lifetime of people time having 1/3 approximately being spending in sleep , sufficient fine sleep is able to make people , energetic keeping clearheaded in daytime job. Person needs sleep , the animal not only also with self peculiar way sleep. What is sleep so after all? People have experienced a long range process of cognition for finding the answer.

The earliest, starting only from the superficial, saying that “when the person or animal in a stationary state is sleep.” However, in People sleep is not a motionless, and this definition is not able to separated sleep from anesthesia and coma. In the early 30s of this century, a French physiologist believe that sleep is such a state : “The human body’s internal needs, so that feeling of sexual activity and sporting activities be suspended immediately so that it would be appropriate to stimulate the awakening” , Later, by recording the EEG, people learned about the sleep EEG changes in the nature of sleep have a further understanding of the sleep is defined as: “Because of the functional activities of the brain caused by animals, physical activity is low, given appropriate stimulus allows the fully awake. ” But such a definition is still unsatisfactory, because sleep gastrointestinal fluid secretion, growth hormone synthesis and many other physiological active than awake. From the awareness of sleep the whole process can be seen as sleep is not as simple as we imagine.

Insomnia all night tossing, it is difficult as sleep soundly, painful anomaly; while some sleepiness in patients with head all day long but drowsy, and even meetings, lectures will be snoring when the masterpiece is difficult to self-control. So sleep, how did this happen?

There are two views, the feeling that sleep is a passive process, and the other is that sleep is an active process.

First, we should know what caused the material basis of sleep – the human brain. The human brain from the brain, cerebellum, midbrain, pons, medulla five parts, the midbrain, pons, medulla also collectively referred to as the brain stem. Sleep is now considered to have a direct relationship between the brain and brainstem.Scattered in a number of brainstem neurons, these cells with a criss-cross between the nerve fibers connected with each other to form a network structure, namely, the brain stem reticular formation.

Some nerve cells also aggregated into a certain function of the nerve nuclei. Body peripheral sensory system, such as pain, temperature sense, touch, hearing, vision and other receptors are stimulated to produce nerve impulses, the incoming brain stem reticular formation, that is causing the excitement, the brain stem reticular formation and through numerous nerve fibersdiffusion in the cerebral cortex and projected onto the impulse conduction to the cerebral cortex, the brain in the excited state, this time sober person who; and when the external sensory stimulation is weak, the incoming impulse to the brain reticular formation is very weak, not enough to to maintain its excited state, the brain’s excitability subsequent superoxide skin significantly reduced, when reduced to a certain extent, people could sleep.

This is consistent with our life experiences , and when entering a quiet, dark and comfortable environment, we will soon be sleepy, but in a noisy place rocked, but tossing and can not sleep.Can be seen that the weakening of external stimulation helps sleep, that is, the generation of sleep is a passive process.

Since the production of sleep is a passive, why will emerge insomnia? Why still dream during sleep? Further studies confirmed that sleep is a physiological function of the brain, brain stem nuclei of the nerves can be released some material effect on the network structure to induce or maintain sleep, animal studies show that if the destruction of these structures can make animals a few days can not fall asleep within; on the contrary, if the increase of these substances by electrical stimulation of the release or application of exogenous compounds to replace these natural substances to treat, they can induce or maintain sleep. More and more studies show that people sleep, the brain can indeed produce some material to maintain sleep, they are called “sleep factor”, has been found that as many as dozens. While awake also need to maintain a clear factor. This shows that sleep is an active process. Perhaps in the near future, we may be able to promote them through synthetic sleeping or awake promoting substances to treat patients with insomnia or sleepiness.