Posted on 01/11/2002 5:46:27 PM PST by Oxylus
Question:
Why does looking at a bright light or sunlight sometimes make people sneeze?
Carl Owens,
Corcoran, California
Louis Ptacek of the University of Utah's Howard Hughes Medical Institute replies:
Sneezing provoked by sudden exposure to intensely bright light is known as the photic sneeze reflex. It is not uncommon'about one in 10 people are photic sneezers. Some studies suggest it may be due to an accidental crossing of nerve signals involved in normal sneezing and pupil dilation. But the photic sneeze reflex occurs only after someone has been adapted to the dark for at least five minutes. Even photic sneezers' pupils will adjust normally (without triggering a sneeze) if they go in and out of bright light for short periods of time, so the real mystery is why an extended period of darkness makes a difference. The reflex is not troublesome to most people, but it is of considerable interest to scientists. The trait travels in families'approximately 50 percent of children born to photic sneezers are photic sneezers themselves'so it should be possible to identify one or more genes that are responsible. The photic sneeze reflex may also relate to other reflex phenomena. For example, people with epilepsy frequently have seizures induced by strobe lights, and visual stimuli can precipitate headaches in many migraine patients. Studying the photic sneeze reflex is likely to improve our understanding of sensory pathways in the nervous system, as well as the circuitry of the sneezing reflex.
The post-coital phase of orgasm sometime causes me to sneeze....
Me too. I always wondered about it.
Now, don't anyone flame me for this one. I'm just telling you an idea concerning the "group yawning effect" that I came across a while back.
It runs parallel to the "group gag reflex". You know, when one person gags or vomits, invariably other people (me included) will feel like gagging too. The theory I heard for that was it is a survival mechanism. When we were monkeys or early humans (or whatever- I don't want to get involved in an evolution vs creation debate) presumedly the group would have all been eating the same thing. If it was spoiled or poisonous it would have been imperative for the group to quickly vomit up what they were eating if one member became ill.
Likewise, with the yawning thing. When it got evening and the alpha male or Mongo the chief decided it was time to go "beddy bye" then it was time for all the little monkeys to go beddy bye. This increased their survivability by keeping the noise level and activity to a minimum while nocturnal predators were roaming around. So the yawn is perhaps a signal that we are hardwired to pick up on.
I don't know how much credence I give it and like all these "theories" it can't really be proved anyway so it relegates it to a mere interesting conversation piece. I do know that sometimes in the Army in a large barracks I would be the first one awake. I'd just lay there quietly so as not to disturb my fellow soldiers. But invariably, someone else would soon wake up and then another and another- even if nobody was making any noise and it wasn't time for us to wake up. Pretty soon everybody would be kicking around in their bunks. So maybe we are programmed for these types of group input? Who knows.
Well, I seem to remember seeing a sea horse yawning in the Oral Office when Clinton was in orifice.
I'll leave it to your imagination and hope you've had breakfast already.
One who sneezes on exposure to bright light, and breaks wind while he sneezes, is said to have photic-phartic sneeze reflex.
What's with you pinging me to these type of threads? (Same warped sense of humor-Thanks!)
Now, I've read that yawning is a 'stay awake' mechanism.
More beneficial were the laughs we all got from your post. Thanks! Everyone was terrific. Better than Letterman..how is that for meter!
I have a rare variation - if I am with someone else who sneezes first, I seldom have to myself. If I am alone, I sneeze every time.
Yep, I've heard that one too. The whole "increasing oxygen to the brain" thing? But it's counterintuitive. Not that pure intuition should be part of the scientific method. Seriously, what do you associate a yawn with- getting more awake or getting more sleepy?
Invariably, if one person in a group yawns, many more people in that group will yawn. As a way of demonstrating just how strong this effect is I would challenge all the posters and lurkers who have read this thread to 'fess up' and say whether they felt like yawning after reading mykdsmom's number 4 post. Yawning is obviously(imho) a sort of signal like the gag reflex. And if it's a signal- what does it or what is it supposed to communicate? Well, I get sleepy when I yawn/see someone yawn (try the experiment of faking a yawn in the middle of the day in a crowd- it's astonishing- why should anyone be sleepy in the middle of the day?). It's also my assertion that the yawn effect works better in a group who's members are very familiar with one another. IE a yawn will have less effect on a crowded subway than within a work group (like an Army platoon). Then again, maybe Army work is just boring ;-)
Where do I sign up for my informal (or is it honorary?) doctorate degree? I think Clinton had to go to Israel for his. Maybe they'll have one within Public Transport distance... Next theme- memes.
...Perhaps someone should inform all of the highway departments...you know, so that they understand what they are doing when they put strobe flashers inside Red Traffic Lights.
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