Photic sneeze reflex is an inherited, genetic trait. If one of your parents has this reflex, you have a 50 percent chance of inheriting ACHOO syndrome, too. The number of sneezes could be as little as two or three, but some people report as many as 40 or more successive sneezes. Sitting in a brightly lit house might not trigger a sneeze. But you may start sneezing if you step into direct sunlight. The study found that fewer than 27 percent of photic sneezers interviewed were able to recall a parent with the same sneeze reflex.
The same study, however, did find a link between photic sneezing and a deviated nasal septum. One theory is that sneezing involves the optic nerve. A change in light may stimulate this nerve, creating the same sensation as having an irritant in the nose. This sensation could possibly be responsible for the sneeze. Another theory is that light exposure causes eye tears, which briefly empty into the nose.
This might also cause temporary irritation in the nose and sneezing. Some people with photic sneeze reflex are also sensitive to other types of stimuli. For example, if you have a history of photic sneeze reflex, receiving an eye injection — such as anesthesia prior to eye surgery — may trigger a sneeze or two.
This is because an eye injection can stimulate the trigeminal nerve. This nerve provides sensation to your face, and it also signals the brain to sneeze. Some people even have successive sneezes after eating. This can happen after eating spicy foods or a large meal. Spicy foods may trigger sneezing as receptors in your nose detect capsaicin, a chili pepper extract. To avoid sneezing, some people shield their eyes before exposure to the sun and other bright lights by wearing sunglasses, scarves, or even a hat.
Photic sneeze reflex can be dangerous in some situations, such as when operating a car or other motor vehicle. Sudden exposure to bright light could trigger successive sneezing, affecting your ability to maintain control of a car.
Because sneezing causes involuntary eye closure, multiple sneezes while driving could cause a traffic accident. Photic sneeze reflex can also pose a danger to airplane pilots. This nerve is in close proximity to the optic nerve, which senses, for example, a sudden flood of light entering the retina. As the optic nerve fires to signal the brain to constrict the pupils, the theory goes, some of the electrical signal is sensed by the trigeminal nerve and mistaken by the brain as an irritant in the nose.
Hence, a sneeze. But because this harmless albeit potentially embarrassing phenomenon doesn't seem to be linked with any other medical condition, scientific study of the subject has been scarce. Research has done little more than document its existence and attempt to gauge its prevalence. No rigorous studies exist, but informal surveys peg 10 to 35 percent of the population as photic sneezers. A study in the s showed that the trait is autosomal-dominant—the gene is neither on the X nor Y chromosome and only one copy of the gene has to be present for the trait to be expressed—so if one parent sneezes when they look at a bright light, about half of his or her children will, too.
The genetic culprit remains unidentified, but scientists are starting to take an interest in trying to find out. Epileptic seizures are sometimes triggered by flashing lights and migraine headaches are often accompanied by photophobia. But until he and his colleagues find the right families for their study, the photic sneeze reflex will remain something of a genetic novelty act, like the ability to roll your tongue. Although a paper in the journal Military Medicine raised concerns that light-induced sneezing might endanger fighter pilots, for whom a split second of lost vision could be lethal in certain situations, such fear was largely put to rest when a small study found that wearing sunglasses eliminated the effect.
Beyond that blip of gravitas, papers published about photic sneezing have largely leaned toward the whimsical end of the spectrum. Consider one publication that took advantage of the then-raging acronym fad and suggested an alternate name for the photic sneeze reflex: Autosomal-dominant Compelling Helio-Ophthalmic Outburst syndrome, or, of course, ACHOO.
Eye and Ear physician directory to find the right ophthalmology eye or otolaryngology ear, nose and throat specialist. Koichi Tsunoda 2 years, 10 months ago. I remember when I was jeunior highschool student. Sometimes I felt to try to sneeze but could not. That time my friend suggested me to look at the sun or light, it mekes me seeze easily. Now I recognized it was true. Suzanne Day 2 years, 10 months ago. Chip R 2 years, 9 months ago.
I once heard that it was a trait that prompted newborn babies to sneeze once they were exposed to light in order to clear their passages. Lisa C 2 years, 8 months ago. This was such an interesting topic! My son has OCA1 albinism albino and every time he goes outside on a sunny or overcast day, he will sneeze. We make a joke of it now that he is older. Once he gets that first sneeze out, he is fine. Anna Franz 2 years, 7 months ago. Well, Personally when I want to sneeze but I still need a little bit of tingling to sneeze I looked up to the sun and it complete.
Samir 5 months ago. I have on a few occasions seen my phone activate it, but rarely. I believe there is a response to either ultraviolet or infrared light or something else in the invisible spectrum. It would be interesting to have a study on these wavelengths and it might be the root cause when combined with the genetic component.
Ryan Jaslow 4 months, 3 weeks ago. Thanks for reading and sharing your experience, Samir. I agree some more research on this topic would be fascinating to see! Expert Chats. Eye and Ear Communications Monday, Mar 20, Read More.
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