Nation & World

Q&A - Ticklishness has no discernible purpose


Staff Writer

Q: Why are people ticklish?

A: "The big explanation is that nobody has a clue," said Nicholas Christenfeld, an assistant professor of psychology at UC San Diego. "Tickling turns out to be almost entirely mysterious, from start to finish."

Christenfeld and his colleague Christine Harris ran two experiments to investigate the nature of ticklishness. They showed subjects a comedy before and after tickling, but being in the mood for humor didn't affect responses. They also used a machine to tickle subjects, who laughed even without the interpersonal element of fake fighting.

"It's not just funny to be tickled -- it's something more reflexive," Christenfeld said. "But it doesn't answer the question about why you laugh and smile when someone pokes you in the ribs."

He said one theory suggests ticklishness evolved as a defense mechanism. People are often ticklish in areas they would protect in combat, such as the ribs and stomach. And people can't tickle themselves -- the touch must be as unpredictable as an assault. But the theory doesn't explain why people react to tickling with laughter.

"The laughter makes people want to poke you there," Christenfeld said. "Parents like to tickle their children because they look like they're having a great time."

Christenfeld said ticklishness might be no more than a mistake in the wiring of the nervous system. But tickling can definitely play a social role in friendship and romance. The intimacy of the behavior also brings together the members of families, especially parents and young children.

"It's just more or less your bonding time with the child," said Song Ramos, assistant director of Mulberry Child Care & Preschool in Temecula. "You're showing interest in the child."

Ramos and her co-workers said parents sometimes use tickling to lead to a lesson about the parts of the body. Pre-school teachers also tickle children as a form of positive interaction.

"It's just so easy," Ramos said. "It's something that makes them feel good. I know that I do tickle them in the classroom just to make them laugh."

Please direct your science and technology questions, along with your name and hometown, to Katie Burns at (760) 740-5442, or 207 E. Pennsylvania Ave., Escondido, CA 92025.


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