![]() Can photic sneezing be dangerous? Occasionally. He wrote in his Book of Problems, "Why does the heat of the sun provoke sneezing?" His best guess: "Because the heat of the sun doth dissolve." Whatever that means. Ultimately, we don't really know what causes photic sneezing.Īnd it's a scientific mystery that has existed since antiquity. This suggests that the reflex isn't a classic reflex generated in the brain stem - such as the reflex to move your hand away from a hot stove - but involves deeper brain processing.Ĥ) It's possible the trait is a leftover of evolution: that at one point, it was advantageous for a baby's survival to be more prone to sneezing. Ptáček, a neurologist at the University of California San Fransisco who has studied the reflex, says in an email.ģ) It could also be something a bit more deeply rooted in the brain: A 2010 study out of Switzerland found that the visual cortices in the sneezers' brains are more easily excited than those in non-sneezers. "The precise pathway is not known," Louis J. One paper in the journal Eye speculates that genetic variation might bring the optic and cranial nerves in closer contact. ![]() This might explain why only some people do it. "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," author Karen Schrock explained in a 2008 Scientific American article. But that wouldn't explain why some people have photic sneezing and others don't.Ģ) Another possibility: Perhaps the optic nerve, which responds to light, gets its wires crossed with the fifth cranial nerve, which controls some facial movements. One possibility is that the sudden activation of one component of this system - i.e., the constriction of pupils and tearing up in the face of bright light - spontaneously activates another component, sneezing. Over the years, researchers have floated a few theories for why the sneezes happen.ġ) Photic sneezing may have its roots in our parasympathetic nervous system, which controls many of our involuntary actions. There are just a couple dozen papers investigating the condition. (Yes, really.) It stands for "autosomal dominant compelling helio-ophthalmic outburst syndrome."īut since it's not a pressing medical concern ("It’s not like you’re crippled to go outside," Manuel says), photic sneeze reflexes haven't been researched very well. In the 1970s, the condition was formalized under the acronym ACHOO. These patients would reliably sneeze when quickly exposed sunlight, flash photography, and, in a few cases, even ultraviolet light. Further investigation revealed that it wasn't just any light that brought on the sneezing, but sudden flashes. The phenomenon was first described in the 1950s, after a French doctor discovered several patients sneezing in response to the light of his ophthalmoscope, (the device doctors use to examine the retina). The purpose of sneezing is to clear unwanted irritants or germs from the nose. Photic sneeze reflexes don't seem to make any sense at first. How the photic sneeze reflex works Jeroen / Flickr A bright light "will push it through," he says. It's also helpful if he feels a sneeze coming on and just can't get it out. Manuel agreed with my characterization that it's a bit of a superpower. I called Manuel because I wanted to know what it's like to live with the photic sneeze reflex, a genetic quirk that affects between 15 and 30 percent of people (it's more common than green eyes) but is very poorly understood. And the brighter the light, the better: "I have a bright LED light in my basement - if I look straight at it, I’m going to go." ![]() "I can shoot off five, six of them in a row, just looking at bright light," he tells me. "I can’t fly, but I can sneeze," he says during a phone call.Įver since he was a kid, Manuel, a 40-year-old resident of southeastern Michigan, knew that if he stared into a bright light - the sun or a bright lightbulb - he'd automatically sneeze. Adel Manuel doesn't have any mutant superpowers, but he has the next best thing: He can sneeze on command. ![]()
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |