The Science of Tickling: Why We Can’t Tickle Ourselves and How Robots Can Help

Laughter is a fascinating human response, often triggered by the delightful act of tickling. Most of us have a ticklish spot somewhere on our bodies, and it’s usually a fun game to find it. Whether it’s just above the knee, the back of the neck, or those sides that make us burst into fits of laughter, being tickled by another person is a universal experience. But have you ever wondered why we laugh when tickled? Recent scientific findings reveal that this seemingly whimsical reaction has roots in our primal instincts, serving as a defense mechanism against little creepy crawlers like spiders and bugs.

When we’re tickled, even by the gentle touch of insects, our bodies react with a shiver, signaling that something might be crawling on us. This ticklish sensation can trigger a panic response. It’s this unexpected and uneasy feeling that leads to the intense laughter we experience when someone tickles us, catching us off guard.

Surprisingly, even if we’re aware that a tickling is imminent, the fear and unease of another person’s touch can still provoke laughter. Some individuals are so ticklish that they can’t help but burst into laughter even before being touched.

Now, the question arises: Why can’t we tickle ourselves? The full explanation remains a bit of a mystery, but research has shown that our brains are finely tuned to anticipate the sensations generated by our own movements. Just as you don’t consciously focus on the sensations of your vocal cords when you speak, your brain dismisses many self-generated sensations. When we attempt to tickle ourselves by, for instance, grabbing our own sides, our brain expects this self-contact and prepares for it. This anticipation eliminates the element of surprise and unease, causing our body to respond differently compared to when someone else tickles us.

Brain scientists at the University College London have identified the cerebellum as the part of the brain responsible for preventing self-tickling. Located at the base of the brain, the cerebellum constantly monitors our movements and can distinguish between expected and unexpected sensations. Expected sensations, like the pressure of your fingers on a keyboard, are filtered out, while unexpected sensations, such as someone tapping you on the shoulder, grab the brain’s attention. This built-in response likely developed in early human history to detect potential predators and other threats.

Although self-tickling remains a challenge, modern science and technology have found a way to outsmart our brains. British scientists have developed a robotic solution that allows individuals to tickle themselves. This robotic tickler is operated using a remote control joystick, and a soft foam attachment delivers the tickling sensation. Even with just a fraction of a second’s delay between the person’s action and the robot’s response, subjects have reported that the sensation is remarkably similar to being tickled by another person. So, with the assistance of technology, you can, in a way, tickle yourself with a robotic partner.

In conclusion, the mystery of tickling, the science behind our laughter, and the brain’s role in distinguishing self-tickling from external tickling continue to intrigue researchers. As our understanding of these phenomena deepens, we may uncover even more fascinating insights into the human brain and its unique responses to the world around us.