Why is laughter contagious? Blame your brain.
Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent six days a week. I still remember the time I was sitting in class when the teacher asked me to read a passage out loud. Just seconds before, some classmates had started giggling about something, and it was contagious. As I read aloud, I tried to stay serious, but kept dissolving into fits of laughter. I knew our strict, no-nonsense teacher would not be impressed, but I couldn’t stop. You’ve probably been there, too: laughing when you’re not supposed to, trying to hold it in, and somehow that only making it worse. So why is laughter so hard to control? Laughter is not completely under your control Research suggests that there are two kinds of laughs: helpless, involuntary laughter (like the kind I was experiencing in that class) and polite, social laughter (like when your friend tells a joke and you laugh because you like your friend, not because the joke is funny). Different parts of the brain drive each type of laughter. …








