Wikipedia: Sleep/Talk

To Larry Sanger: You are trying to be a guardian of the neutral point of view, but on the way you risk being a roadblock on the way towards education. By adding "Researchers do not know what is the role of sleep", you inserted a blatant fallacy into this text. I could forgive a random surfer or visitor. But it is Larry Sanger who should stand for integrity and progressive nature of Wikipedia. Who does not know the role of sleep? Vertes? If you said "Researchers do not know all the function of sleep" you might be closer to the truth because there are many in the research community who still push on with some of their own theories. If a simple experiment: learn the [Towers of Hanoi]?, get sleep or do not get sleep, check the performance, clearly indicates deficit in procedural learning for sleep deprived, no reasonable person would question the role of sleep in learning. Now multiply it by dozens of experiments, hundreds of researchers, hundreds of papers, ... do you still have doubts. Naturally, go on the net search and you will find thousands of pages with hundreds of theories, but that's not what should make up your mind. Imagine searching the net about the theory of evolution in the 1860s (the most valuable findings in sleep&learning research date to late 1980s and the 1990s). This time I apologize for inevitably harsh words: you are not helping Wikipedia with this. If you are not sure about some texts, put your doubts in Talk or sign in under a different name! -- Piotr Wozniak

I think the wording could be better--I agree with Piotr that it is well established that consolidation of memory occurs during sleep, but that by no means should elevate this simple fact to a "purpose". I'll change the text to something I think better reflects current knowledge; feel free to edit. --LDC

Piotr, making an edit that requires you to add essential text to your article is not a roadblock, it's one of the most important kinds of edits one can make, for purposes of keeping people honest. Now, last I heard, it was an enormous mystery to sleep researchers what the purpose of sleep is, though there were a number of theories. I am willing to concede that in the intervening years (ten?), researchers have concluded that sleep does have at least one specific, well-demonstrated function; but in that case, it would be a good idea to say who the (main) researchers are who have demonstrated this, how it was demonstrated, and so forth--all the details you (finally and helpfully) mention above. As you can see, I stand behind this particular edit 100%. Now I hope that you will edit the article and enlighten us in a way that will shame me into silence. I'll be watching. --LMS

Naturally, shaming Larry into silence would be a very lowly purpose. I put some links to popular scientific articles at sleep and learning. If they survive future edits, any reasonable person can draw his or her own conclusions about the role of sleep (don't we all pause why should we waste 1/3 of our lives on a seemingly useless state of unawareness and vulnerability? -- the greatest minds in the research community have a very simple answer to that: optimizing memory storage in condition of information excess). If anyone is interested in my own popular scientific summary and practical applications of knowledge about sleep, see: http://www.supermemo.com/articles/sleep.htm. I will try to explain why I do not take on the challenge of arguing my case at Piotr Wozniak -- Piotr Wozniak

Not just humans sleep - other mammals certainly do and other animals have similar rest states. Anyone want to tackle including these. -rmhermen

According to what I've read in body-building literature, sleep is necessary for muscle growth and repair. Sleep probably serves numerous other physical purposes, which should be included in the article. - TS

Why should we "disconnect" the brain in order to "regenerate" muscle? It is like shutting down the government in order to fix a highway. If muscle impulsation had to be cut off, it could have been done by "paralysis" at the level of the [medulla oblongata]?. If you mean GH?, it can also be released without getting "dumb" for 8 hours. You can rest your muscles ok without getting any sleep. The belief that sleep is needed for muscle regenration comes from the fact that the organisms puts various defense mechanisms against sleep deprivation that would slow down registering new generalized and non-interfering memories to a crawl. Those defenses provide for a breakdown of the endocrine anabolic regulation which ulimately leads to "feeling awful" and "unrefreshed" and "broken down" -- Piotr Wozniak

But sleep doesn't only "disconnect" the brain--it also involves physical immobility. It is quite likely true that physical regeneration of muscle is also an important use of sleep. I'm not sure it even makes sense to speak of "purpose" when talking about biological systems--that implies a telos, and biological systems aren't like that. Human-designed things have purpose: we put wings on a plane in order to provide lift. But evolved things are different; things often have many different and unrelated uses. Things that first appeared for one use (like jawbones) often evolve into something completely different (impedance-matching sound conductors). Writing about the role of sleep in learning is a worthy cause; but calling it "the purpose" of sleep is almost certainly wrong. --LDC

You can easily verify the evolutionary purpose of sleep by removing the demand for its individual functions. You bet, once you do not need to rewire your neural network, you will lose the need to lose consciousness. And the muscular system will help itself. As I said earlier, the "disconnect" (if indeed needed) can happen at a lower level. Would you argue that we cannot say "the role of heart is pumping the blood" only because there are other regulatory benefits of its action? -- Piotr Wozniak (note that immobility is also a result of the disconnect; not to let the muscles rest but to prevent you from injuring yourself while motor centers are in action in REM)

: The first sentence above is quite demonstrably false, since no such experiment is even possible with current technology. No matter how much you protest that you know "the purpose" of sleep (and by the way, I assume you do understand that in English this implies the only purpose) you have not, and cannot, do the experiments necessary to verify that claim, so it is irresponsible and unscientific to make it. The brain is millions of times more complex than present science is even capable of investigating, and all sweeping claims about its major functions are unverified theories at this point. Even the very detailed stuff we think we know about language and perception from the likes of Chomsky, Pinker, and others is not scientifically verifiable yet. Your articles are good stuff, and would be appropriate here in one of two ways: either as they are now, clearly marked as commentary, or else modified to hedge the wild unsubstantiated claims. --LDC

Teleonomy? is a concept in biology that deals with the apparent goal-directedness of biological systems. From a teleonomic perspective it is perfectly correct to speak of purposes in biology. See http://www.freedomsnest.com/mayr_biophil.html for more. - TS

Yes, I suppose that's as rational as speaking of "selfish genes", as long as it's clear that these are specialized uses of the words. My remaining objection, then, is to speaking of "the purpose" rather than "one purpose". --LDC

Sleep does not mean physical immobility as stated above. Only in REM sleep does the inhibition of striated muscle occur, and even then there are frequent bodily movements in REM sleep. Bodily movements are common in all other sleep stages. As a technologist in a Sleep Disorders Center, I have watched thousands of sleep studies and have yet to see anyone sleep without moving. A common example of motor activity in sleep, accessable to those who are not sleep technologists - sleepwalking. --rpsgt244