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Subscribe to RSSSometimes, a funny thing happens when Dr. Roberta Pagon looks directly into the sun. She sneezes. Not just once though, but usually three times.
She's not the only one in her family who sneezes when sunlight hits their face -- two of her children also react by sneezing three times in a row. And now a grandchild does it, but only sneezes once.
Odd coincidence? Not really, says Pagon, a pediatrician in the division of genetic medicine at Seattle Children's Hospital. This tendency to sneeze at sunlight is known as the "photic sneeze reflex," and it's hereditary.
Not only is there a genetic basis for "sun sneezing," Pagon says the number of times people sneeze in response to light also appears to run in families.
This scientific discovery happened in a very unscientific way. Pagon and her genetics colleagues were sitting at the same table during a birth defects conference when the conversation shifted to discussing the sun and sneezing. Much to their surprise, they learned that 4 out of 10 of them were affected by this strange reaction. "One person said it was common for people in his family to sneeze five times; in my family it was three times, and another person said once," recalls Pagon.
They quickly did what years of medical training had taught them -- they coined an acronym for it: ACHOO syndrome, or Autosomal Dominant Compelling Helio-Ophthalmic Outburst. Autosomal dominant stands for the way the 'sneeze gene' is inherited; an individual has a 50-50 chance of passing this trait on to a child. "Compelling" because it was well, interesting, or at the very least, quirky. "Helio" meant sun, "ophthalmic" meant eye, and "outburst" the end result. They even wrote up a paper about the peculiar phenomenon.
Although this reaction might seem unusual, it's not that uncommon. By one estimate,18% to 35% of people get a tickling sensation in their nose when their eyes meet intense sunlight. Some folks may also get this weird response to bright artificial light, such as the eye doctor's or dentist's light or a photographer's flash.
Driving out of a tunnel may trigger the reflex or leaving a movie theatre on a summer's day, says Nicolas Langer, PhD, a neuropsychology researcher the University of Zurich, who has studied the photic sneeze reflex. Often "it's just the change of a dark location to a bright (very sun exposed) location" that brings on the reflex, he explains.
In his research published in the journal PLoS ONE, Langer compared the visual reactions of 10 sun sneezers to 10 people without this reflex. Volunteers were hooked up to an EEG machine so the scientists could measure their brain and neural responses when exposed to bright light.
Their results suggest that "the 'photic sneeze reflex' is not a classical reflex that occurs only at a brainstem or spinal cord level," says Langer. "It seems to involve other cortical areas" of the brain.
As for why it happens, Langer offers two theories. One is that the visual system in the brain is more sensitive in photic sneezers. When it gets overstimulated by light, this co-activates regions representing the nose (the somatosensory system), which then triggers a sneeze.
A second possibility is that two nerves (the optic nerve and trigeminal nerve) are too close together in photic sneezers. Langer says light may cause stimulation of the optic nerve in the eye, which then coactivates the trigeminal nerve in the face, and results in an achoo reaction.
Solar sneezes could be an occupational hazard if you're an airplane pilot, baseball outfielder, sky diver, punt-return specialist, or high-wire acrobat. But for roughly one of out four people, it's merely something curious that makes them a little different from the next guy or gal.
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Actually, this trait has been very useful throughout the years. Whenever I feel the need to sneeze but I can't, I just glance into a very bright light to coax the sneeze out. It works almost every time. Sunlight is better, but any bright light is good. I just thought everybody could do this.
Totally agree :) I'll stare into dim energy-saving lightbulbs to coax out the sneeze if I have too, and it works....
Likewise.
It's very common in some ethnic groups, including mine, and has been documented for years. I'm pretty sure I saw mention of this 'scientific discovery' at least a decade ago. :)
Though it's strangely gotten less intense as my light sensitivity from Lupus has increased. I wonder if the inflammatory response is short-circuiting the sneezing.
I've always looked a bright light to stop sneezing and it works.
Interesting. I have always found that if I feel a sneeze coming on and it won't come, if I squint at a bright light it will make me sneeze. I've always given this advice to people. I didn't realize that it was a "hereditary condition".
This photic sneeze reflex was first described by Dr. Steve Peroutka, a neurologist, back in the 80's. He reported it in the NEJM.
Correct Neuro, other than the genetic component, this isn't news. I was "diagnosed" decades ago, although I didn't need a diagnosis, I was in my 30's and had figured it for myself. When I would witness it in other people, I'd always ask them if it was a common response for them. About 2 or 3 out of 10 said it was.
I thought I came up with the term "photic sneezer" until someone said to me as we walked outdoors and I sneezed, "Aha, you're a photic sneezer!" I guess I must have heard the phrase somewhere before. I've been carrying a handkerchief in my back pocket for decades!
I thought everyone did it. I learn something new everyday. Like you, if I need to sneeze I just look toward the sun and then sneeze two or three times.
I have been doing this all my life. I thought it was my allergies but my sisters and brother do this also. Weird. I will share this with them.
I also look at lights or the sun when I have a sneeze that just won't come out... and I thought everyone could do this! :)
Same here, and I thought so, too!
Difference is you look at the sun when you have a sneeze that wants to come out. For those of us with this, we have no choice but to sneeze when we walk outside......every time. I sneeze a minimum of 5 times and have gone upwards of 10 but 5-6 is the norm. I also sneeze when the sun comes out from behind the clouds, I go from the shade to sunlight or take off my sunglasses.
Whenever I come out of a dark movie theater into the sunlight, I start sneezing! Can't wiggle my ears, but I can sneeze on cue!
Well, It sure is nice to finally be dianosed as having ACHOO Syndrome rather than saying as an excuss it's only allergies. Of course I end up sneezing 5-10 times after seeing intense sunlight or bright light after leaving a dark room. I inherited this from my mother, and her sisters were the same way. Intense sneezing for up to 5 minutes. Good thing I stop using the scalpel when it happens LOL.
My mom did this and so do I. We both sneeze 3 times. My husband thought I was really weird and said it was just my allergies acting up. But none of my kids do this but they have their dad's brown eyes and where mom and I have blue eyes. Wonder if it makes a difference?
I tend to sneeze at least 20 times when I get started. It is exhausting. Sunlight sometimes triggers it. But, usually it just starts out of no where. My dad and sister do the same thing. (btw dad - hazel eyes; sister and me - brown) I always just tell people jokingly that I am allergic to sneezing.
I was in USAF pilot training in the late '60's and this frequently happened to me when popping out of an overcast into a bright sky. Sneezing while wearing an oxygen mask is no fun. We couldn't take antihistimines or any other drugs so I just toughed it out. I certainly wasn't going to report this to a flight surgeon lest I be grounded.
The Air Force spent over a million dollars studying this phenomenon. It seems they were concerned that a pilot would come out of a cloud, hit the sunlight, sneeze and fog his goggles.
My youngest does this. I don't notice it in the older two though. I'll have to pay more attention. But the little one has always sneezed when sunlight hits his face. Someone told me when he was a baby that he's a sun-sneezer. Nothing to do about it, just one of those funny things.
Using it to get a sneeze out is a new tack. Thank you.
I've gotten caught being right at the sneeze's edge and it hangs up ... I'll go run to a bright light bulb if sunlight isn't available, mouth halfway open (silly!!) and I can usually coax the stubborn sneeze to finish! :)
There is nothing more discouraging than an unfulfilled sneeze! :D
My son did this the first time I took him outside after he was born. My Mom said " It's bright out." He still does this at 29. My Mom, an RN for over 40 years, apparently was familiar with this phenomenon. I had never heard of it until that moment.
My husband has always seemed puzzled by my sneezing at the sun, but I thought he was the weird one because he didn't know what I was talking about. Come to think of it, I haven't noticed any of our 3 daughters doing it either. Looks like I'm the odd one out.
I got into trouble in Chemistry class in high school for staring at a light to coax out a sneeze.
My teacher, Mr. Eeles thought I was nuts when I tried to explain it to him. I should see if I can send him a copy of the pLOS paper... I want an apology.
I have this condition, I'd say 25 to 50% of the time I walk outdoors, I sneeze once, sometimes twice.
Question for others who this happens to...do you have an over-sensitivity to bright light? I find that when someone in on-coming traffic has their high-beams on, I find it so inconsiderate that I want to drag them from their cars and smash their faces into their high beams. Others don't seem to get as bothered by that. I'm starting to realize that this is not a road rage problem but maybe it just doesn't bother other people because the bright light doesn't bother them. To me, high beams are painful.
It seems that there is a degree of sensitivity of this action. Some people require direct sunlight, others require extended direct light, and some require only bright light or very little at all. For example, I have to look at the sunlight and usually sneeze twice. Doesn't work with artificial light such as dentists light etc.
For other people, it could be that the nerve is extremely sensitive and over-activated by light. In your case it sounds as if your optic nerve is overly sensitive to bright light.
I was wondering this when I read the article. Yes, I do have bright light sensitivity in addition to the sneezes. I can't even stand my kids shining flashlights near me. It hurts my eyes. And I get red welts in the sun even after about 5 minutes if I don't have high level protective sunscreen on, too. I have fair skin and burn badly, too. I have brown eyes, though, but my father and sister had green, as well as a son with light eyes, so I have the gene.
Interesting...and I have always used the light to sneeze, too...lol.
I don't sneeze easily, but looking at the sun will coax one out every time. Even better, if I pop a piece of mint gum in my mouth, and then look at the sun, I'm guaranteed to sneeze. I like the way sneezes feel so I do it on purpose. :) My husband thinks I'm a little strange...
My children and I all do this! How funny that it actually has a name...
The photic sneeze reflex was first described by Dr. Steve Peroutka in the 80's - he reported it in the New England Journal of Medicine.
I'm really and truly puzzled that this is considered unusual.
I was well into my 20's before I met anyone that *wasn't* familiar with the concept of sneezing at bright lights. Wonder if it's a latitude thing, like MS. (I grew up near the 43rd parallel)
It was common in the Acadian population in New Brunswick, which is east of Maine. I've met very few people with it, however, in California.
I've done this too since I was an infant. I am very light sensitive as well and I can tell the sensation is triggered by my pupils contacting. (1) I don't exactly get road rage when I see high beams, but I am very annoyed. It seems the car behind me has the lights shining in my rear view mirror, or, if we're stopped at a light, my side mirror, and I find it is blinding. I have to block it with my hand from shining directly in my eyes or I cannot see at all. (2) When I go to the eye doctor I have to make sure they give me the mildest eye dilating drops or else my eyes are often dilated until the next day. When the doctor views my eyes with the light the light after-image stays with me for such a long time that I cannot read the charts or anything for a good 20 minutes (this happens with photograph flashes too). (3) I must have complete darkness at night when I'm sleeping; if I get up for some reason I have to be careful and walk around in the dark or else the brightness of having a light on (even a night light) stays with me and I can't get back to sleep since I keep seeing that glare with my eyes closed.
Wow...me too! If a light shines in my eyes it stays for a long time and I am half blinded. I really hate that...arrgh. The side mirrors at night with those bright lights are awful!
Sneezing when you see a bright light or look at the sun is no big deal! Now, keeping your eyes open when you sneeze--that's talent!!
Finally an explanation! I first noticed this when I was about 15 (60 years ago) and I was always told I was imagining it or I was a little crazy.
I've always sneezed when first exposed to bright sunlight, and the reason seems obvious. When we sneeze, we close our eyes. It's protective.
When my daughter was little, she used to say "I'm allergic to the sun" She always sneezes in the sun, still does. I just thought it was her, but sure didn't know it was this common!
I'm another one. And like many others in this thread, I will also sometimes use the sun or a bright light to help bring on a sneeze I can feel wants to come. But other times the sun itself will cause them right out of the blue.
Never bothered to keep count though. Usually 2 or 3, I think, but they tend to be deep sneezes.
That is very interesting, because when a friend says they have the need to sneeze but can't, I have always said to look at the sun! I never knew why I would say it, or remember when I first heard about it.
I just thought that everyone did this! I had no idea there was a whole population in the world that never sneezes at the sun. I assumed it was because of the warm air hitting your nose from the sunlight. Now I will have to poll everyone I know. LOL.