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I haven't slept for a day, but feel fine. It is commonly known that one needs 8 hours of sleep, but this is sometimes not true. Is it okay if I sleep 8-9 hours the next day, as long as it only happens every month?

EDIT I ended up sleeping at 6 AM and got a fresh 8 hours of sleep, waking up at 2 PM. I woke up a couple of times due to dog jumping on me, sleeping next to me, and I ended up dreaming as well (I don't know the mechanism behind it, but wake up just before your last REM cycle and you will dream vividly).

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I'd say you can manage with 4 hours per day, but then you would sleep a bit more during the weekend. If you're interested in the topic you could try searching for relevant books about sleep deprivation on goodreads.com - I'm sure there's something for everyone :) –  SkyHiRider Dec 20 '13 at 8:16
Insomnia is an inability to sleep on a natural sleep wake cycle. Mania can provide so much excess energy that sleep is not required. If this happens frequently you should visit a doctor with questions about Bipolar disorder. As Bipolar onset is late adolescence early adult hood. –  caseyr547 Dec 25 '13 at 2:56
@caseyr547: Where did I state this in my post? –  Jossie Dec 25 '13 at 3:19
@caseyr547: the predominant symptom according to the DSM-IV-TR is difficulty initiating or maintaining sleep, or suffering from nonrestorative sleep, for at least 1 month. –  Jossie Dec 25 '13 at 3:33
@Jossie a psychotic episode is like a seizure the excess dophamine (or whatever) overloads synapses and breaks pathways also forming rouge pathways. medicalnewstoday.com/articles/248159.php –  caseyr547 Dec 25 '13 at 4:40
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2 Answers

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Here's why people need to sleep:

The brain does its "cleaning up" during sleep. As cells in the nervous system are active, waste products are produced. In the rest of the body, waste removal is carried out by the lymphatic system, but this system does not extend to the brain. Instead, cerebrospinal fluid (CSF) must be pumped through the brain tissue in order to flush waste back into the circulatory system where it can be excreted by the liver. Pumping CSF seems to require a great deal of energy, and researchers speculate that this energy expenditure is incompatible with the intense metabolic demands of brain cells during wakefulness. Also, cells in the brain shrink considerably during sleep, resulting in a 60% increase in interstitial space which allows CSF to wash more freely through the brain tissue. The consequence is significantly faster clearance of neurotoxic waste (e.g., β-amyloid).

  1. http://www.sciencemag.org/content/342/6156/373
  2. http://stm.sciencemag.org/content/4/147/147ra111
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Could you summarize the information in the papers within your answer, please? –  Chuck Sherrington Dec 24 '13 at 23:08
The "cleaning" hypothesis is just one, and it's a rather new one. The debate about the function of sleep has been going on for a long time, and the community has not settled on maintenance cleaning being the answer. There are also rest hypotheses (that neural cells need rest, but can't rest individually because they're coupled to other neurons, so they have to rest in large groups, requiring sleep) and there's also a hypothesis that sleep serves a memory and learning function (consolidation processes between hippocampus and cortex) –  Keegan Keplinger 2 days ago
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As mentioned in one of the TED talks by Russell Foster, we need sleep not only for resting or cleaning up, but also for developing memories.

In addition, a good sleep has also requirements (mostly environmental); e.g. no-light, no-noise room etc.

Here is the talk: http://www.ted.com/talks/russell_foster_why_do_we_sleep.html

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