Photic sneeze reflex, officially known as ACHOO syndrome, causes sudden sneezes when exposed to bright light. This reflex ...

If so, you're not alone — as many as 1 in 3 people display this reaction. This reflex, called the photic sneeze reflex, has been observed since at least the fourth century B.C., when the ancient ...

For starters, you’re not crazy: The sunshine really can make you sneeze. It's called photic sneezing, according to McGeorge, and it happens when you go from the inside to the outside.