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Double-yawn effect

  1. Mar 15, 2010 #1
    One person yawns. Give it 2-5 seconds and the person next to him yawns aswell.

    Why does this happen? Is it psychological?
  2. jcsd
  3. Mar 15, 2010 #2
    You can check out some of the thinking on why it's contagious here. Interesting that they mention human to dog yawning contagiousness. I've yawned a time or two after seeing my dog yawn right after a nap. Maybe they should check out for reverse dog to human contagiousness also.

  4. Mar 17, 2010 #3
    The wiki article is kind of a collage.

    I thought this paragraph was pretty peculiar:

    For me yawning seems like crossing a threshold from forced, sustained activity or vigilance to relaxation. The deep breath and the whole "pandiculation" thing result in a more sloppily relaxed, less sharp state. This sentence: "It signals tiredness to other members of the group in order to synchronize sleeping patterns and periods." made much more sense to me than the earlier proposition that it increased group vigilance. In my experience yawning is more likely to precede sleep than anything else. Who really feels more alert and vigilant after yawning?

    The best mechanism I've heard of for how a yawn might be "contagious" is the proposed mirror neuron one. Mirror neurons could account for a huge mass of things, but as far as I know it's a notion that hasn't been more than just sketched out.
  5. Mar 17, 2010 #4
    I had a similar reaction to the wiki article zooby. Here's another article that discounts some of the things in the wiki article. According to this one, there's no basis for thinking it removes excess CO2 from the body, something I was told a long time ago. Anyway, I did yawn once while reading this one. :cool: Anyone else?

  6. Mar 18, 2010 #5
    If yawning is a means to keep the brain cool, why don't we see joggers yawning all the time?
  7. Mar 18, 2010 #6
    Thats because our body temperature is kept pretty much the same. It is balanced by swetting. You dont get a remarkable temperature while jogging.
    Plus, the jogger is breathing fast and regularly while jogging. So the brain isnt in a desperate need of oxygen either. But I guess the "brain-is-in-need-of-oxygen-so-yawn" theory is proven wrong now anyways.

    Wiki tells us that yawning is the reflex which is created by the stretching of the eardrums and inhaling. How come that creates the reflex anyway?
  8. Mar 18, 2010 #7


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    Just by reading the title :biggrin: but I was already feeling sleepy - it was just the tipping point.
  9. Mar 18, 2010 #8
    "...even reading, or thinking about yawning, or looking at a yawning picture can cause a person to yawn..."

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