We know pretty well what happens during sleep. Our body inactive,we lose consciousness, and we fail to respond to things that are happening around us,We also know a great of what takes place in our body during asleep,we know how the muscles relax ,how certain vital functions continue,what happens to our circulation,our temperature, and so on.But what how do we go to sleep? What actually takes place that enables us to fall a sleep? Strangely enough,the most we can say is there are a greater many theories about this.And so far,it has been impossible to prove whether these theories are right or wrong.
For example,it was once believed that we fell asleep when blood in our body shifted out or into an important organ. Well,this theory is no longer believed because we now know no such shift of blood takes place. Another theory no longer believed that the chain of nerve cells in our body, which act as pathways in our nervous systems, were actually broken, and then we fell asleep.One possibility was that the impulse s to the brain were shut off by our body, and that as a result we a were no longer in a "wakeful state".There are even theories about falling a sleep which claim that it is positive instinct.This means that it's not just a matter of stopping wakefulness, but a positive process by which the body instinctively puts itself to sleep.
There is a whole group of chemical theories about falling asleep too.These claim that some substances that the body needs to stay awake is used up, and so we go to sleep, and during sleep this substance replenished. Or that certain toxic substance accumulated when we are awake and these produce sleep.So here we still have a mystery about about one of the most common and important thing we do.It's as if our body knows s that we need sleep to restore our tired organs and tissues and in one way or another sees to it that we get this sleep
Every night we close our eyes and go off to another world-the world of sleep. When we are awaken,it's as if we have come back from a journey,except we don't know how really happened to us.We may know the dreamed or were cold or hot.But what else did we do? What was happening to our body while we slept?. One important thing happened, of course, was that the muscles relaxed.I f someone raise our gently while we slept,it would be quite limp and we wouldn't resist.One of the reasons we take horizontal position when we go to sleep is to allow this muscle relaxation, A set of muscles that doesn't relax during sleep, how ever,is around the eyes and the eyelids. These muscles are contracted to keep our eyes closed.
During night's sleep, our body does a lot of moving. We may move just one part of the body or another, or turn completely to change our position. Some people move more, some less , and it also depend on how tired we are. the temperature,what we ate before we went to bed , and so on. The average person moves about 20 to 40 times a night, but we move about 30 seconds in each hour or a few minutes in a whole night.When we are awake,each one of us reacts differently to external events,but when we are asleep, we all react almost in the same way to whatever message our sense organ pick up. Noise,light,heat, smells produce practically the same reactions in all sleeping persons.
The question is that,what happens inside our body during sleep? ,The blood continues to circulate of course, but the heart beat is slower ,we breathe more slowly, too, and not as deeply as when we awake, Digestions goes on an its usual rate. The liver and kidneys continue working, but a slightly decreasing rate. Our body temperature decrease as much as one degree. Perspiring in general may increase, but is less active in the palms of the hands and soles of the feet during sleep than when we are awake . It is not true, as people think, that we sleep more deeply at certain time during the night. In any one night, we may go from shallow sleep to deep sleep, over and over again
For example,it was once believed that we fell asleep when blood in our body shifted out or into an important organ. Well,this theory is no longer believed because we now know no such shift of blood takes place. Another theory no longer believed that the chain of nerve cells in our body, which act as pathways in our nervous systems, were actually broken, and then we fell asleep.One possibility was that the impulse s to the brain were shut off by our body, and that as a result we a were no longer in a "wakeful state".There are even theories about falling a sleep which claim that it is positive instinct.This means that it's not just a matter of stopping wakefulness, but a positive process by which the body instinctively puts itself to sleep.
There is a whole group of chemical theories about falling asleep too.These claim that some substances that the body needs to stay awake is used up, and so we go to sleep, and during sleep this substance replenished. Or that certain toxic substance accumulated when we are awake and these produce sleep.So here we still have a mystery about about one of the most common and important thing we do.It's as if our body knows s that we need sleep to restore our tired organs and tissues and in one way or another sees to it that we get this sleep
Every night we close our eyes and go off to another world-the world of sleep. When we are awaken,it's as if we have come back from a journey,except we don't know how really happened to us.We may know the dreamed or were cold or hot.But what else did we do? What was happening to our body while we slept?. One important thing happened, of course, was that the muscles relaxed.I f someone raise our gently while we slept,it would be quite limp and we wouldn't resist.One of the reasons we take horizontal position when we go to sleep is to allow this muscle relaxation, A set of muscles that doesn't relax during sleep, how ever,is around the eyes and the eyelids. These muscles are contracted to keep our eyes closed.
During night's sleep, our body does a lot of moving. We may move just one part of the body or another, or turn completely to change our position. Some people move more, some less , and it also depend on how tired we are. the temperature,what we ate before we went to bed , and so on. The average person moves about 20 to 40 times a night, but we move about 30 seconds in each hour or a few minutes in a whole night.When we are awake,each one of us reacts differently to external events,but when we are asleep, we all react almost in the same way to whatever message our sense organ pick up. Noise,light,heat, smells produce practically the same reactions in all sleeping persons.
The question is that,what happens inside our body during sleep? ,The blood continues to circulate of course, but the heart beat is slower ,we breathe more slowly, too, and not as deeply as when we awake, Digestions goes on an its usual rate. The liver and kidneys continue working, but a slightly decreasing rate. Our body temperature decrease as much as one degree. Perspiring in general may increase, but is less active in the palms of the hands and soles of the feet during sleep than when we are awake . It is not true, as people think, that we sleep more deeply at certain time during the night. In any one night, we may go from shallow sleep to deep sleep, over and over again
