♪ [Squeaks laughs].

Gosh, you’re so ticklish, Squeaks! Are you ticklish?

If you are, you know it! And if you’re not, then you probably wonder what all the fuss is about. Either way, tickling is pretty strange!

Lots of things make us laugh, but that’s usually because we think they’re funny. Tickling is different! It has to do with your sense of touch, which helps you learn more about the world.

When you sense a touch, the part of your body that feels something touching you sends a message to your brain. Then, your brain decides how to respond to the feeling. So when Squeaks gives me a high five... [hands clap] ... my hand sends a signal to my brain, which figures out that what I’m feeling is my favorite robot rat's hand!

Well, the same kind of thing happens when someone tickles you! The body part that’s being tickled sends a message to your brain, which figures out what’s happening and tells your body what to do. For me, that’s usually to start giggling and squirming!

Scientists aren’t completely sure why we’re ticklish. But they’ve studied the problem very carefully, and have some good ideas. Squeaks, where are you ticklish?

Oh, your belly? I'm ticklish in my armpits! In fact, most people are ticklish on and around body parts like their bellies and under their arms.

Now, think about where you are ticklish, and think about what you do when you get tickled there. Most of us kind of curl up, or hug our middles, or squirm away as we try to stop being tickled, even if we’re laughing at the same time. And under these very ticklish outside body parts are some pretty important inside body parts, like our hearts and stomachs.

So scientists think that when we’re tickled in those places, we cover them up and try to get away because we’re sort of trying to protect the important body parts underneath from getting hurt — even if we don’t really think about it. That can also explain why tickling makes us laugh. Scientists think we laugh as a message to the person that’s tickling us — again, even if we’re not really doing it on purpose.

And that message is: stop, you win! That may sound kind of … well, funny … but it’s like we’re practicing doing things that might keep us safe. And, scientists also think this is part of why we can’t really tickle ourselves.

Go ahead and try! You just can’t tickle yourself — at least not in the same way someone else can. That’s because when your brain gets the message that you’re being tickled, say from your belly, it also realizes that another part of your body — your own hand — is what’s doing the tickling.

But if the tickle comes from someone else, we definitely feel it! Ah! Stop it, Squeaks!

Thanks for joining us! If you want to keep learning and having fun with Squeaks and me, hit the subscribe button, and we’ll see you next time here at the Fort! ♪.