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Sleep deprivation and circadian rythms

  1. Jan 31, 2005 #1
    I notice distinctly apparent changes in myself under sleep deprivation: cognitive skills increased, mood increased, focus is typically good and distraction is no longer a powerful nemesis.

    My first experiments involved a period of no sleep for approximately 5 days during which i took some interestingly creative yet mostly incohesive notes. At current i am a college student and i have time spread throughout the day to do as i please.

    I wish that i could never sleep but i am a realist. Ive learned that a typical circaidan rythm, ie when people will most likely be tired, is from 2-6 am and pm. Whilst not sleeping at all, i have noticed a severe onrush of fatigure around 6pm and also one around 9-11 am.

    What i am looking for is the optimal schedule which would yield the least amount of sleep possible to still be fully functional. I recall Einstein took naps frequently but did not sleep through the night?

    some input would be appreciated.
  2. jcsd
  3. Jan 31, 2005 #2


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    Your first and second paragraph contradict each other. You might want to rethink this idea of depriving yourself of sleep.

    A circadian rhythm is any rhythm of approximately 24 h in length that continues to exist in the absence of any external time cues (zeitgebers). Humans are diurnal in their activities (active during the daylight hours), and sleep coincides with hours of darkness, when melatonin synthesis and release is highest. There can also be some other periods of tiredness/sleepiness during the day after meals (known as post-prandial fatigue).

    Some people have circadian rhythm defects that would lead them to either wake up excessively early or excessively late compared to other people, or have disturbed sleep patterns, or no regular sleep patterns. Some of these are known to occur due to gene mutations, others commonly occur in blind people who cannot use light to keep their rhythms synchronized to the 24 hour day/night cycle (our circadian rhythms are not exactly 24 hours, and light serves to "entrain" us or synchronize us to 24 hour time; if we cannot perceive any light, our sleep/wake cycles drift out of phase with the day/night cycles).

    If you'd like to know how circadian rhythms occur at a molecular level, there is a good animation at this site: http://www.hhmi.org/biointeractive/animations/mol_mod_mamm/mamm_frames.htm

    Note, it's a bit outdated now, but it gets the key concepts across well.
  4. Jan 31, 2005 #3


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    I recall a journal club presentation where the subject touched on sleep deprivation and the subjects of the study "getting over" their fatigue and lethargy following the deprivation said they felt better. They all subjectively reported feeling fine, alert and not tired, however objective testing demonstrated that they perfomed very poorly on tests they had performed well on in sessions prior to the deprivation. You might want to rethink the severe deprivation and try a less aggressive "sleep when you feel tired" as you suggested in your later comment.

    To Moonbear and others, since we're on the subject of circadian rhythms, I came across an article of circadian sneezing (prompted by the photic sneezing thread), pretty interesting...
  5. Feb 1, 2005 #4
    let me correct what i was trying to say. i have tried extreme deprivation at one time, but not longer do it. Now it is at most 24 hours. If it is not circadian rythm than i dont know what it is; but somewhere, i was reading and there are times of the day when for whatever reason people are less energized and more prone to sleep. I believe it had something to do with magnetism or the moons gravitational effects. I dont wish to stop sleeping completely, just far lass than i do now. I believe there will be bonuses in this schedule. And i would say i dont have a sleeping pattern, but id rather be sleeping in the afternoon than at night. Im thinking maybe a 6 or so hours of sleep per day in the afternoon.
  6. Feb 2, 2005 #5
    Photic sneezing thread? Where is it? What is it?
  7. Feb 2, 2005 #6


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  8. Feb 3, 2005 #7


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    To add to my own anecdote:

    After a recent all nighter, I left for university at 7:30am. Although my mood was hardly elated, I felt strangely focused. At the beginning of my first class at 9:00am, I felt sharp as a tack, and took in the lecture very well. Up until that last five minutes that is. At which point I was no longer capable of even taking notes. By 10:00....CRASH and BURN!!! I suppose I could have had more coffee at that point to try to keep me going, but I decided against it. As a result, the rest of the day was a write off. Would I recommend sleep deprivation on purpose? Absolutely not! :smile:
  9. Feb 3, 2005 #8
    Well you see total sleep deprivation wont get you far. what you need to do is sleep very little, perhaps 6 1 hour naps a day, or 3 two hour naps- so long as it totals 6. I hate sleep. it is impossible to escape sometimes, when you want to get up most you feel the need to lay inert. A state of complete motionless waste. Im always sharp as a tac, 6 hours a day is the magic number.
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