Science of Laughter is serious Business

[Mira]

THE ASSOCIATED PRESS

Published: March 31, 2010

WASHINGTON - So a scientist walks into a shopping mall to watch people laugh.

There's no punchline. Laughter is a serious scientific subject, one that researchers are still trying to figure out.

Laughing is primal, our first way of communicating. Apes laugh. So do dogs and rats. Babies laugh long before they speak. No one teaches you how to laugh. You just do. And often you laugh involuntarily, in a specific rhythm and in certain spots in conversation.

You may laugh at a prank on April Fools' Day. But, surprisingly, only 10 percent to 15 percent of laughter is the result of someone making a joke, said neuroscientist Robert Provine of Baltimore, who has studied laughter for years.
Laughter is mostly about social responses rather than reaction to a joke. "Laughter above all else is a social thing," Provine said. "The requirement for laughter is another person."

Over the years, Provine, a professor with the University of Maryland Baltimore County, has boiled laughter down to its basics. "All language groups laugh ‘ha-ha-ha' basically the same way," he said.
"Whether you speak Mandarin, French or English, everyone will understand laughter.... There's a pattern generator in our brain that produces this sound."

Each "ha" is about one-15th of a second, repeated every fifth of a second, he said. Laugh faster or slower than that and it sounds more like panting.
Deaf people laugh without hearing, and people on cell phones laugh without seeing, illustrating that laughter isn't dependent on a single sense but on social interactions, said Provine, the author of the book Laughter: A Scientific Investigation.

"It's joy, it's positive engagement with life," said Jaak Panksepp, a psychology professor at Bowling Green University. "It's deeply social."

Panksepp studies rats that laugh when he tickles them. Sound silly? It's on YouTube and in scientific journals. It turns out that rats love to be tickled. They return again and again to the hands of researchers tickling them, Panksepp's video shows.

By studying rats, Panksepp and other scientists can figure out what's going on in the brain during laughter. And it holds promise for human ills.

Jeffrey Burgdorf, a biomedical-engineering professor at Northwestern University, has found that laughter in rats produces an insulin-like growth-factor chemical that acts as an antidepressant and anxiety-reducer. He thinks that the same thing probably happens in humans, too.

http://www2.journalnow.com/content/2010/mar/31/science-of-laughter-is-a-serious-business/c_1/