Why do eyes shut when sneezing?”
Actually, no one really knows. ”It is unclear, but scientists theorize that we close our eyes to protect them. We may be protecting our eyes from microorganisms and particles from our sneezes,” said Dr. Bonnie Henderson, director of comprehensive ophthalmology at the Massachusetts Eye and Ear Infirmary. But it could also be simply because a sneeze is a kind of bodywide reflex in which a lot of muscles contract, not just in the nose and throat but also those in the diaphragm, the abdomen, thighs, back, even sphincters (which is why some people with stress incontinence may urinate slightly when they sneeze). Researchers aren’t sure exactly why the sneeze reflex happens, but whatever neurological message tells the eyes to close probably comes from a primitive part of the brain called the medulla oblongata in the brain stem, Henderson said. And, it’s not just an irritation in the nose that can trigger a sneeze; some people, probably because of genetics, have a photic reflex, which makes t
