why do we sneeze when we see bright light?
In: Biology
photic sneeze reflex. this is the official medical term for the phenomenon where exposure to bright light triggers sneezing. It affects around 18-35% of the population. so kind of far from being able to use the royal ‘we’. 😂
i get it too. i find it very handy. i hate feeling like i have to sneeze and not being able to.
It’s not totally understood but basically it’s thought that the nerves that connect your eye’s iris are also connected to the thing that makes you sneeze. When you see bright lights and your iris contracts, it also triggers the sneeze. https://en.wikipedia.org/wiki/Photic_sneeze_reflex
Fwiw, I call them “solar sneezes” and it happens to about 1/4 to 1/3rd of the population.
It’s called a photic sneeze reflex. It’s a genetic/inherited thing that affects 20-30% of the global population. To my knowledge, there’s no real conclusive reason we know as to why it happens.
Autosomal Dominant Compelling Helio-Ophthalmic Outburst (ACHOO) syndrome
We don’t really know. My favorite theory is that those of us with ACHOO have optic nerves that developed too close or intertwined with our trigeminal nerve. So when the optic nerve is overstimulated, the nerve signals pass to the nasal cavity instead.
The wires in your brain cross sometimes, specifically the ones for “activate sneeze” and “light is too bright”, resulting in the stimulus of bright light triggering a sneeze
I had heard that it provides an evolutionary benefit. Something about how we used to live in caves/dark areas. When ancient humans exit the caves and encounter bright light, sneezing would clear the sinuses of fungal/bacterial germs? Not sure how true this is but sounds good to me haha
I thought everyone had this. Until I told a mate about it and he looked at me like I was weird. Turns out not everyone does sneeze when exposed to a bright light. The worst is when you’re driving in the morning sun. You just know a sneeze is coming.
I did not even know we did this. How bright does the light have to be?
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