What is the chemical process of sleep?
600107
It hasn't been 100% figured out yet, which is why they haven't made any sleeping pills that actually give you "good proper" sleep. Things like valium or any other kind of sleeping pill like that knocks you out but doesn't give you real rejuvinating sleep.
935380
The quality of  sleep is much more important  than its quantity.\n    In  order to  have a  truly effective  rest and  relaxation during\n    sleep, it  is good as  a rule to  drink something before  going to\n    bed, a  cup of milk  or soup  or fruit-juice, for  instance. Light\n    food brings a  quiet sleep. One should, however,  abstain from all\n    copious  meals,  for  then  the  sleep  becomes  agitated  and  is\n    disturbed by nightmares, or else  is dense, heavy and dulling. But\n    the most  important thing  of all  is to make  the mind  clear, to\n    quieten the emotions and calm the effervescence of desires and the\n    preoccupations which accompany them. If before retiring to bed one\n    has talked a  lot or had a  lively discussion, if one  has read an\n    exciting or intensely  interesting book, one should  rest a little\n    without sleeping in order to  quieten the mental activity, so that\n    the brain does not engage  in disorderly movements while the other\n    parts of the body alone  are asleep. Those who practice meditation\n    will  do well  to concentrate  for a  few minutes  on a  lofty and\n    restful  idea,  in  an  aspiration towards  a  higher  and  vaster\n    consciousness. Their sleep will benefit greatly from this and they\n    will largely  be spared the  risk of falling  into unconsciousness\n    while they sleep.\n\n\n  To sleep well one must learn how to sleep.\n\n      If one is physically very tired, it is better not to go to sleep\n    immediately, otherwise one  falls into the inconscient.  If one is\n    very tired, one must stretch out on the bed, relax, loosen all the\n    nerves  one after  the another  until one  becomes like  a rumpled   cloth in one's  bed, as though one had neither  bones nor muscles.\n    When one has done  that, the same thing must be  done in the mind.    Relax, do not concentrate on any idea or try to solve a problem or   ruminate on impressions, sensations or emotions you had during the   day.  All that  must be  allowed to  drop off  quietly: one  gives   oneself up, one  is indeed like a rag. When  you have succeeded in   doing this,  there is always  a little  flame, there -  that flame  never  goes out  and  you become  conscious of  it  when you  have managed this  relaxation. And  all of a  sudden this  little flame\n    rises slowly  into an aspiration  for the divine life,  the truth,\n    the consciousness of  the Divine, the union with  the inner being,\n    it  goes higher  and  higher,  it rises,  rises,  like that,  very\n    gently. Then everything  gathers there, and if at  that moment you\n    fall asleep,  you have the best  sleep you could possibly  have. I\n    guarantee that if you do this carefully, you are sure to sleep,and\n    also sure that instead of falling  into a dark hole you will sleep\n    in light, and  when you get up  in the morning you  will be fresh,\n    fit, content, happy and full of energy for the day.\n\nWhen the sun sets, a kind of peace descends upon the\nearth and this peace is helpful for sleep.\n\nWhen the sun rises, a vigorous energy descends upon\nthe earth and this energy is helpful for work.\n\nWhen you go to bed late and get up late, you\ncontradict the forces of Nature and that is not very\nwise.
491528
When you sleep you go through different cycles, most notably, REM. This period is where you are deepest asleep and you dream.  Its the climax of your sleep cycle. When people nap, they generally don't go through their entire cycle, hence they wake up and don't feel as though they slept at all.  Generally, you need to sleep at least 3 hours to go through your entire sleep cycle, anything shorter than that, and you will feel groggy and tired when you wake up.  Instead of taking naps, try just resting and relaxing without sleeping, for 20-30 minutes.  That is generally the best thing to do when you are tired during the day.  It refreshes you, and won't wreck your sleep schedule, like naps will do.
493138
Biologists believe that during waking hours there are chemical changes (like harmful substances) and physical changes (wear and tear on cells) that are corrected when we sleep. Different stages of sleep are believed to have different functions. For example, REM sleep (when we dream) is believed to be when we consolidate learning and make memories. Slow wave sleep (the times when we are really quiet and not dreaming) is when restoraton is believed to take place. \n\nAs somebody said earlier, if we dont sleep we eventually die. Sleep deprived Rats became uncoordinated, lost weight due to climbing metabollc rates and appeared to starve to death though they were fed. Their immune functon was also compromised but cause of death was not really clear. \n\nMoreover, If you dont sleep you get haggard and ugly, its hard to concentrate, your family will eventually hate you for being a grouch and you will lose your job for making mistakes and telling off your boss. (if you dont kill yourself while driving to work first.) Everything is better with sleep :)
965466
6 to 8 hours of sleep is necessary for the human body.  \n\nIts Importance:\n\nSleep is a natural part of everybody's life, but many people know very little about how important it is, and some even try to get by with little sleep. Sleep is something our bodies need to do; it is not an option. Even though the exact reasons for sleep remain a mystery, we do know that during sleep many of the body's major organ and regulatory systems continue to work actively. Some parts of the brain actually increase their activity dramatically, and the body produces more of certain hormones.\n\nSleep, like diet and exercise, is important for our minds and bodies to function normally. In fact, sleep appears to be required for survival. Rats deprived of sleep die within two to three weeks, a time frame similar to death due to starvation.\n\nAn internal biological clock regulates the timing for sleep. It programs each person to feel sleepy during the nighttime hours and to be active during the daylight hours. Light is the cue that synchronizes the biological clock to the 24-hour cycle of day and night.
1090574
To answer this question you need to understand the sleeping stages.\nMany people think of their sleeping bodies as if they were cars parked for the night--motionless, engines off, headlights dimmed. But sleep is an amazingly complex state of being. As we sleep, muscles tense and relax. Pulse, temperature and blood pressure rise and fall. Chemicals crucial for well-being course through the blood stream. The brain, like a Hollywood director, conjures up fantastic stories, complete with a plot, characters and action. \n\nYou don't simply "fall" asleep. You descend slowly through different levels. As you close your eyes and drift off, you enter the first stage of what is called quiet sleep. Your brain produces irregular, rapid waves, and muscle tension decreases. You breathe smoothly, and mundane thoughts float through your mind. If roused, you might jerk awake quickly and deny that you'd slept at all. \n\nIn stage 2 of quiet sleep, your brain waves become larger, punctuated by occasional sudden bursts of electrical activity. You've definitely crossed the border between wakefulness and sleep. If someone lifted your eyelids gently, you wouldn't waken; your eyes no longer respond to stimuli. \n\nAs you descend into stage 3, your brain waves become slower and bigger. In this state of deep slumber, your bodily functions slow down even more. Finally stepping into stage 4, you reach deepest sleep, the most profound state of unconsciousness. On an EEG (electroencephalogram), your brain waves would appear extremely large and slow. You are so "dead to the world" that a thunderstorm might not wake you. \n\nThis step-by-step journey into oblivion usually takes more than an hour. Then you begin to climb upward, moving rapidly through the same sleep stages as before, not all the way to full wakefulness but in active sleep. Because the pupils dart back and forth, this stage is called Rapid Eye Movement or REM sleep. (The four stages of quiet sleep are often referred to as non-REM or NREM sleep.) \n\nDuring REM, your brain waves resemble those of waking rather than of quiet sleep. The large muscles of your torso, arms and legs are paralyzed, although your fingers and toes may twitch. You breathe quickly and slowly, the flow of blood through your brain accelerates. REM sleep is the time of vivid dreaming, and if wakened, you'd probably recall a fragment of a fantasy. \n\nAfter about ten minutes in REM sleep, you descend the sleep staircase again. The entire cycle of REM and NREM stages takes roughly 90 minutes. Early in the night, the periods spent in the deepest stages of quiet sleep are longer. In the second half of the night, REM sleep predominates. By morning, you go around the sleep circuit four or five times. \n\nThis pattern changes gradually throughout life. From infancy to adulthood, REM periods dwindle to less than a quarter of a night's sleep. By their thirties, men spend less time in the very deep stages of NREM sleep. Women begin to sleep less deeply in their fifties. By age 65, both sexes spend half as much time in deep sleep as they did when they were 25. The lighter sleep stages increase later in life, and REM shrinks to about a fifth of total sleep time.
58587
A chemical reaction is a process that results in the interconversion of chemical substances. The substance(s) initially involved in a chemical reaction are called reactants. Chemical reactions are characterized by a chemical change and it yields one or more product(s) which are different from the reactants.
455971
Non-REM sleep (NREM), accounts for 75-80% of total sleep time: \nStage 1-  The stage is sometimes referred to as somnolence, or "drowsy sleep". It appears at sleep onset (as it is mostly a transition state into Stage 2. In this period, the subject loses some muscle tone, and conscious awareness of the external environment: Stage 1 can be thought of as a gateway state between wake and sleep. \nStage 2, The EMG lowers, and conscious awareness of the external environment disappears. This occupies 45-55% of total sleep. \nStage 3, functions primarily as a transition into stage four. Overall it occupies 3-8% of total sleep time. \nStage 4 is true delta sleep. It predominates the first third of the night and accounts for 10-15% of total sleep time. This is often described as the deepest stage of sleep; it is exceedingly difficult to wake a subject in this state. \nStage 5, or Rapid eye movement (REM) sleep, associated with dreaming.REM sleep is predominant in the final third of a sleep period, its timing linked to circadian rhythm and body temperature. Sleep proceeds in cycles of NREM and REM phases. In humans, the cycle of REM and NREM is approximately 90 minutes. Each stage may have a distinct physiological function. Each sleep stage is not necessarily uniform. Within a given stage, a cyclical alternating pattern may be observed.
670101
There are a lot of considerations, like the amount of 'deep sleep' or REM (rapid eye movement) time.  It turns out that things like blood pressure and melatonin (hormone related to sleep) follow the diuranal cycle.  Yes, the sleep should ideally be at night.  That is how the human animal evolved on the planet earth.
116526
It is not a chemical answer.  It is Biological Chemistry, or the chemistry of a living creature.  It is caused by a surge of adrenaline released by the Pituitary Gland in your brain.
440933
You are your brain, but your brain is doing a huge number of things at once.  So while it has entered an altered state called "sleep", it's still quite busy, and not completely unresponsive.  It's not just dreaming, but still maintaining your body and processing incoming signals: you can ignore a loud truck on the freeway but still wake up when your child calls your name from the other room.  Or if your bladder commands you to......
613243
Sleep Apnea\n\n\n\nDescription\nAn in-depth report on the causes, diagnosis, treatment, and prevention of sleep apnea.\n\n\n\n\n\nIntroduction\nSleep apnea is a disorder in which a person stops breathing during the night, perhaps hundreds of times, usually for periods of 10 seconds or longer and sometimes for as long as a minute. These gaps in breathing are called apneas. (Apnea literally meaning absence of breath.) It is usually accompanied by snoring. People who have sleep apnea may not even be aware of the condition, but it inevitably causes daytime sleepiness.\n\nSleep apnea is generally categorized as obstructive, central, or mixed. A less severe form of obstructed breathing called upper airway resistance syndrome (UARS) is also worth mentioning.\n\nObstructive Sleep Apnea\nObstructive sleep apnea (OSA), the most common form of apnea, occurs when tissues in the upper throat (or airway) collapse at intervals during sleep, thereby blocking the passage of air. In general, OSA occurs as follows:\n\nOn its way to the lungs, air passes through the nose, mouth, and throat (known as the upper airway).\nUnder normal conditions, the back of the throat is soft and pliant and tends to collapse inward as a person breathes.\nCertain muscles, called dilator muscles, work against this to keep the airway open. Interference or abnormalities in this process cause air turbulence.\nIf the tissues at the back of the throat collapse and become momentarily blocked, apnea occurs. Breath is temporarily stopped. In most cases the person is unaware of it, although sometimes they awaken and gasp for breath.\nIn some cases, the interference is incomplete (called obstructive hypopnea) and causes continuous but slow and shallow breathing. In response the throat vibrates and makes the sound of snoring. Snoring can occur whether a person breathes through the mouth or the nose. (It should be noted that snoring also occurs without sleep apnea.)\nApnea decreases the amount of oxygen in the blood, and eventually this lack of oxygen triggers the lungs to suck in air.\nAt this point, the patient may make a gasping or snorting sound but does not usually fully wake up.\nObstructive sleep apnea is defined as five or more episodes of apnea or hypopnea per hour of sleep that occur in individuals who have excessive daytime sleepiness.\n\nCentral Sleep Apnea\nCentral sleep apnea is much less common. It is caused by some problem in the central nervous system, most likely a failure of the brain to signal the airway muscles to breathe. In such cases, oxygen levels drop abruptly and usually the sleeper wakes with a start. Often people with central sleep apnea recall waking up. They generally experience less sleepiness during the day than people with obstructive sleep apnea.\n\nMixed Apnea\nMixed apnea is the term used when the two apneas occur together.\n\nUpper Airway Resistance Syndrome (UARS)\nUpper airway resistance syndrome (UARS) is a condition in which patients complain about excessive daytime sleepiness and they may snore and wake frequently during the night. However, UARS patients do not have the breathing abnormalities that characterize sleep apnea and they do not show reduction in oxygen levels in the blood. Unlike apnea, UARS is more likely to occur in women than in men. Treatments are similar to those of sleep apnea. It is not known if UARS has any serious health complications.\n\n\nHealthy Sleep\nIn sleep studies, subjects spend about one-third of their time asleep, suggesting that most people need about eight hours of sleep each day. Individual adults differ in the amount of sleep they need to feel well rested, however. (Infants may sleep as many as 16 hours a day.)\n\nThe daily cycle of life, which includes sleeping and waking, is called a circadian (meaning "about a day") rhythm, commonly referred to as the biologic clock. Hundreds of bodily functions follow biologic clocks, but sleeping and waking comprise the most prominent circadian rhythm. T
24298
Detoxification of your system.  And sleep.
308625
by the decrease of lights. As the sun goes down, the pineal gland begins releasing melatonin. Light, whether natural or artificial, will cause the melatonin production to stop. That's why it's good to sleep with the lights off & dark curtains.
250185
It replaces the neurotransmitter in your brain responsible for making you tired. It's the same chemical that is replenished when you sleep, so caffiene makes your body think you've slept when you haven't. If you take too much of it, it can be toxic - and habit forming.
507587
sleep requires different levels of total relaxation of the body muscles (except the diaphragm and the ocular muscles, and i'm talking only skeletal, voluntrary muscles) as well as cortical de-synchronization. i bet you don't want to be standing up for this. have you ever seen a narcoleptic? they go straight into REM sleep which is the strongest point of this inhibition. the fall straight to the ground.
189843
the eyes are dilated from sleep and takes some time for the brain to recognise the light stimuli