Some people say it's to prevent their eyes from popping out of their head. But professors say there are other reasons as to why people close their eyes when they sneeze.

James Strauss, instructor of biology, said people may close their eyes as a response to an allergic reaction.

"It probably helps to protect the eyes and squeezes out a little bit of tears," he said.

These tears help to flush the irritant out of the eyes, Strauss said.

Daniel Treviño, senior instructor in biobehavioral health, said sneezing, in general, is a normal part of the body's functions.

"Presumably it's a protective, normal body response to irritants in our airway passages," he said. "It clears some kind of irritant in our nasal passages and windpipe."

Treviño said he, personally, sneezes with his eyes open. "I don't close my eyes," he said. "It's part of the reflex."

A reflex, Treviño said, is an automatic muscle contraction pattern already built into the nervous system.

"The pattern is triggered, the muscle contracts, and the pattern gets activated without conscious willpower," he said. "The body has it built in."

It's hard to stop a sneeze once it is about to occur, Treviño said.

"You can try to stop a sneeze, but once it happens it's already a pattern hardwired into the brain."

Also, Treviño said, people have their own distinct type of sneeze. "Everyone has a different sneeze all hardwired into the person." For example, one person may have a short, quiet-sounding "Achoo," while others have a long, extended, "Ah-ah-achoo!" he said.

"It's all unique for the person. There's one pattern and that's the way you always do it."

No matter what your sneezing style, however, Strauss said it is indeed possible to sneeze with your eyes open.

"You can definitely override it if you want to," he said.

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