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Medical Internal clocks?

  1. Mar 15, 2007 #1
    something strange happened to me recently, although this is just an anecdotal story, so i appreciate that what i thought had happened may not have been the case.

    anyway, i've noticed that if my alarm clock is consistently set to say, 7 AM, i will wake up roughly around that time even if i've turned the alarm off.

    now is that generally accepted as true within scientific knowledge??

    but listen to this:

    quite recently, i had my alarm set for 7 AM. i remember dreaming about playing a computer game which involved a timer. when the timer reaches 0, game over.

    but in the dream, when the timer DID reach zero- as far as i remember- my alarm sounded.

    now the way i see it there's two possible explanations for this:

    1. it didnt actually happen, i.e. perhaps the alarm sounded some time after the time in my dream expired.

    2. some other cue was present which made me unconsciously aware of the time

    3. the internal body clocks we have can be very, very accurate


    anyone else experienced something like this?
     
  2. jcsd
  3. Mar 16, 2007 #2
    Your alarm clock probably went off before the timer in your dream reached zero. When the alarm clock sounded, you were partly aware of the sound, but you were still dreaming, so you interpreted the sound as the "zero" time on the computer game. Your unconscious mind may have made the connection between hearing the alarm clock and the computer game coming to an end.
     
  4. Mar 16, 2007 #3

    Moonbear

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    To add to what quantumgravity already said, we can also rule out option #3. "Internal clocks" are not that accurate for keeping 24 hour time. They constantly need to be reset by external cues...sunrise/sunset are the common natural cues, but other zeitgebers (time givers) can also be effective, such as the alarm clock, or regular meal times, or anything else that regularly happens at the same time every day. Circadian rhythms in younger people generally run a bit longer than 24 hours (if you removed all time cues from your life, you'd wake up a little later each day than the day before), and become shorter with aging, so that elderly people generally have circadian rhythms a bit less than 24 hours (if you removed all time cues from their lives, they'd wake up a bit earlier every day...somewhat accounting for the prevalence of "early birds" among the retired population). And, when I say "a bit" I mean anything up to about an hour longer or shorter than 24 hours being within the normal range.

    So, if you use stimuli such as alarm clocks to wake you up at the same time every day, your body will predict that time to awaken fairly well, but not down to seconds. Maybe within minutes.
     
  5. Mar 16, 2007 #4
    I've experienced waking up just seconds before my alarm clock sounded, and turning it off.. And I did this for many days in a row. Now I'm out of the rhythm, but I think I would be able to do it again..
     
  6. Apr 14, 2007 #5
    MD,

    Is your room completely black when the alarm goes off?
     
  7. Apr 14, 2007 #6

    Evo

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    I almost always wake up before the alarm goes off, even when it is set for different times.

    I had wondered if I was half awakening and looking at the time on the clock and that caused me to wake up, so I turned my alarm to where I can't see the clock. That has helped me sleep longer in the morning, so it seemed to be part of the problem, but I still wake up before the alarm goes off, which is good because sometimes I forget to set it.
     
  8. Apr 14, 2007 #7
    From time to time I have bouts with insomnia, the kind where I'll fall asleep but then wake up in the middle of the night and not be able to get back to sleep. When this happens it lasts for three or four days. But here's the thing: I wake up very alert, reach over to uncover the clock (I keep it covered because the light bothers me) and the display reads 3:10, night after night.

    Not long ago on TV I saw Wayne Dyer on PBS talking about this very thing. He said that he endured it for years until he finally realized that he was waking up because the universe or Source (as he calls it, which I think means God?) was trying to tell him something. So now he focuses on Source and quietly listens, thereby receiving good ideas.

    Hey great, I thought, I could use some good ideas. So the next time it happened to me, I focused, connected with the source within and without, and quietly listened. Moments of still silence passed. And then, clearly, unmistakenly, the Universe did saith unto me


    YOU NEED MORE SLEEP!


    True story.:smile:
     
  9. Apr 15, 2007 #8
    Thats funny.

    I have experienced both phenoms--the uncanny ability to wake up at 6:07 say 4 days in a row, when the alarm was set for 6:10 as well as the more peculiar early awakenings at the same time hours in advance of whatever the clock was set for, if there even was a clock. I agree with Moonbear to some extent and know too many teenagers who would stay awake til four and sleep til 3 if they had their druthers. There are also studies showing population variability where internal clock can be as much as 32hrs. I think most of can get into a phase lock at different times of the year when the change in external cues is changing at a rate sympatico with our feedback mechanisms at trying to keep the int and ext clocks sync-ed.
     
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