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Becoming smarter, or too much Guyton?

Discussion in 'Medical Students - MD' started by KWBum, Aug 30, 2002.

  1. KWBum

    KWBum Member 10+ Year Member

    Aug 16, 2000
    Ok, so what do you all think of this:

    The rate of blood flow to the brain is regulated, in part, by the carotid and other chemo-, and baro-, receptors.

    We also have a "dive response" that further attempts to preserve adequate oxygenation of the brain, while we "hold" our breath under water.

    Now, I think that it would stand to reason that if we were to spend some quantity of time under water, every day, these changes would become permanent.

    So, say, you spend a total of one hour a day every day for one month holding your breath underwater. One month being sufficiently long to effect physiologic change. The compensatory mechanisms that at first were transient, would eventually become lasting, physiological changes. This, more or less on the general principle of 'adaptation.' That is, the body adjusts to stresses placed on it. In this case, prologed, minimal hypoxia, and an increase in pressure (from being underwater).

    Not that this is the same, by the hypertrophy of the body builder would be analogous. In this case, there should be permanent vascular dilation, and perhaps angiogenesis.

    Essentially, you would wind up with greater blood flow to, and perfusion within, the brain.

    Admittedly, some of the new vasculature would probably only dialate under increased use...but still, it would be available whereas before it would not have been.

    Now, I dunno if this would necessarily make you "smarter" as such, but more fresh oxygenated blood to the brain can't be a bad thing now, can it?

    Oh, and if you were to add to your diving regimen a course of a drug such as Nootropil (piracetam) which putatively increases cerebral perfusion, would this enhance the overall effect?

    So, again, in sum, there would be, at the end of your month of sitting at the bottom of the swimming pool, more blood flow to your brain--permanently!

    Or have I been reading my Guyton too much :laugh: ...?

    [email protected]
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  3. agent

    agent agent, RN 7+ Year Member

    Jul 30, 2002
    Near Chicago
    you're nuts!

    but honestly thats a really interesting theory.

    made for an enjoyable read
  4. GuitarMan

    GuitarMan Guitarman for President 7+ Year Member

    May 21, 2002
    Just last week I was watching a special on the problems associated with deep sea submersion. As part of the special, they showed a competition were divers held their breath and competed to see who could swim to the deepest depth. Due to the effects of pressure on the lungs, several divers returned to the surface only to have their hearts stop and be resuscitated by the medical staff on hand.

    Mind you, these guys didn't go down there all at once, but rather one at a time.

    Now, I haven't been submitting my brain to any stress conditioning, but I'm already smart enough not to do something that stopped the heart of the guy before me. Apparantly these contestants were none the smarter for their ongoing underwater experiences.
  5. KWBum

    KWBum Member 10+ Year Member

    Aug 16, 2000
    You know, that reminds me of "Go to the Widowmaker," by James Jones...anyway.

    I dunno how deep the pool at your house is, but I sure ain't finding any pearls in the ones I've seen.

    Your point is well taken...everything in moderation...even moderation. But we do take certin things for granted. You lift enough weights, you get big muscles. And there it all is, explained nicely in Guyton.

    My diving theory isn't on any one page, but it's all there--all of these physiologic processes take place. The mere act of holding your breath obviously causes more flow to the brain to account for the changing CO2/O2 ratios.

    And we do adapt to repeated stresses, after all. That's in the physiology book too--though momentarily it escapes me as to where.

    So, all in all, I'm curious as to why it wouldn't work--from a physiological standpoint.

    I admit, I might be nuts (say, is this room getting smaller?). But as one reads all this stuff, every once in a while you stare off into space, and go "Hmmmm....what if....?" That's the standard response...Naw, can't're nuts!

    But why!? Why won't it work?

    I admit that my teachers dismiss it all rather summarily--but I'm still not convinced. Maybe someone in Mississippi can ask Guyton himself!

  6. beezar

    beezar Senior Member 7+ Year Member

    Jan 31, 2002
    More oxygen is not necessarily a good thing...oxygen toxicity...the whole creating free radicals thing. For example, in a patient on a ventilator, you don't always want the inhaled oxygen fraction to be 100%. You would lower it to keep the PaO2 like around 90-100 or so, to prevent oxygen toxicity.

    About the brain thing, who knows...
  7. modemduck

    modemduck Senior Member 10+ Year Member

    Jul 17, 2000
    New York, NY US
    Thats a good theory, KWBum but I don't think lack of brain oxygen is what makes a populations range of intelligence. If it was then you would definitely be right; more O2 seems like giving a computer more electricity instead of a faster chip or more ram and expecting it to run faster. It seems as if the organization and structure of the brain is what determines intelligence which can be shown in the amount of folding of the cortex in primates vs humans. I'm not really sure, but it is still a good idea, KW! Besides I am only MS1 and you probably know a LOT more than I do about this subject.

    Columbia P&S 06
  8. omores

    omores sleep deprived 10+ Year Member

    Jul 2, 2000
    I remember reading a long time ago in a reputable peer-reviewed journal such as Weekly World News that Albert Einstein was discovered to have had a much more extensive network of blood vessels in his brain compared to the rest of us.

    The article went on to theorize that he had cultivated this oxygen delivery network in order to make himself more intelligent. The most likely scenario, the article reasoned, was that he spent several hours a day breathing into a paper bag (chronic cerebral hypoxia leading to angiogenesis.)

    So there you go. Might be easier than spending all that time underwater.
  9. wfu2005

    wfu2005 Member 7+ Year Member

    May 8, 2002
    I'm pretty sure that the increased risk of a CVA would outweigh the possible benefits.

    why don't you just hang upside down if you want more blood to the brain? Or you could tilt your bed so that the head is downwards. We'll have a whole bunch more of really smart people with aneurysms.
  10. KWBum

    KWBum Member 10+ Year Member

    Aug 16, 2000
    :laugh: Aaarg! No, no, no...then we'd have to ban legions of kids from spending their summer vacation trying to swim the length of the YMCA pool underwater!

    And I'm not entirely convinced that impersonating a bat is going to induce the same physiologic response.

    Lordy, it seemed reasonable to me...
  11. limit

    limit Molesting my inner-child 10+ Year Member

    Jun 21, 2000
    New York City
    I used to be a competitive swimmer for 4 years and we did regular hypoxic training (going 25-50 yards underwater, repeated over and over). Swim training in itself requires a very rigorous breathing pattern that forces you to hold your breath for quite some time.

    Oh, and if this is AT ALL analogous to the hypertrophy of bodybuilders... Take a bodybuilder and take away his protein ration for 1 month. He will loose all of his hypertrophy.

    In short, yes you adapt to a stress, but it's not permanent. Deconditioning takes place once the stress is relieved for extended periods of time.

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