5 Weird Involuntary Behaviors Explained!

Viewers like you help make PBS (Thank you ?) . Support your local PBS Member Station here: Why we yawn, why we hiccup, twitchy eyes (and more)! Don’t miss our next video! SUBSCRIBE! ►► ↓ More info and sources below ↓ Follow on Twitter: Follow on Tumblr: Follow on Instagram: Our bodies do a lot of weird things, and many of them are completely involuntary