What Happens In Your Brain When You're Chased By An Axe-Murderer

Fear, screaming, and pain are our instincts kicking in.

"Don't go to the basement alone!"

It's the classic line you blurt out whenever you're watching a scary movie, and you know that one of the characters hasn't got long to live. But what if some of our favorite scary movie scenes were reality? How would the human body and brain respond to real-life terror?

A new video from the American Chemical Society's online series "Reactions" explains exactly what happens in the brain when you're being chased by an axe-murderer -- from why we scream to how pain works.

And it turns out that the way your body and brain react is all about self-preservation.

Check out the video above to learn more. 

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