Why can looking at a bright light make you sneeze?

The exact cause of the photic sneeze reflex isn't understood but there are some theories for this kind of reaction.


Asked by: Anonymous

The technical wording for this is the photic sneeze reflex. Its exact cause is not known but it’s been found to run in families. One theory is that photic sneezers are unusually sensitive to light. The irritation caused by emerging out of the dark into the light or staring towards the Sun causes a similar reaction to that from pollen, leading to the sneezing reflex.

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