Adults rule. Because we rule, we get to do mischievous things to our kids. Like tickling them. It’s one of life’s small pleasures to sneak up behind a guileless child, tackle him or her to the ground in an affectionate, roughhouse, big-lug kind of way, then attack armpits, ribs, or neck with wiggly fingers.
The little moppets just love it, too. When I pounce on my son or nephews, they howl in laughter. They curl into a fetal position. They beg me to stop.
Turns out they aren’t kidding. They really want me to stop. At least that’s the conclusion Christine Harris, a Ph.D. candidate in social psychology at the University of California at San Diego, has come to after conducting two studies on tickle. (Not, please note, tickling. Dropping the suffix, I think we can all agree, gives the topic of tickle a more serious air, one more worthy of scientific scrutiny.) Laughter and tickle indeed go together, says Harris, but not because people enjoy the activity. It appears that people’s hee-hawing reaction to tickle is a reflex, just like the one produced when a ball-peen hammer strikes the knee. Which means that I, a big bully, was inflicting what she calls tickle torture on these kids.
Oh dear.
Harris developed an interest in the science of tickle while hanging out one day doing what all good graduate students do, reading Charles Darwin’s The Expression of the Emotions in Man and Animals. In this book, published in 1872, 13 years after the Origin of Species, Darwin speculated that all tickling is social, and he noted the similarities between humorous laughter and ticklish laughter. For example, with both one must have a happy state of mind. In addition to laughter, there are other shared physical reactions, like that convulsive, herky-jerky body motion we’ve all experienced while laughing. Piloerection is also common (which is not what you think, guys, but another reflex, this time of the sympathetic nervous system): in humans it appears as goose bumps; in other, furrier animals, such as angry dogs, it’s what happens when their hackles--the hairs along the back of the neck--rise.
