Random facts about, hey, look over there! Ah, we almost got you.

Why can’t you tickle yourself?

Because the sensation of tickling relies on the concept of surprise. The cerebellum is aware of movements you are about to make before you make them, and prepares the brain for it by canceling the response of the rest of the brain to the tickle. Unless you’re psychic, the brain can’t cancel the response of a tickle coming from someone else because it isn’t away it’s going to happen.

Why are humans ticklish?

Believe it or not, there are two technical terms for tickling. A light moving touch across the skin is called knismesis, and makes you feel more itchy then it does compelled to laugh. It makes you look at the skin to assess what’s tickling you—and it could be a spider or a bug. And that is precisely why humans feel ticklish.

The other kind of tickling—the silly, laughter-inducing kind—is called gargalesis. Scientists theorizes that tickling is a bonding act between parents and their babies, and it’s also a way to increase a young one’s agility and dexterity.

If it’s a natural response built up over years of evolution, how come some people are not ticklish?

Everyone is ticklish—some people have just learned to become very good at sensing when they are about to be tickled. This forces the body to tense up and the brain to cancel the “surprise response” discussed earlier. In other words, non-ticklish people are just lying to get out of being tickled.