The year 2021. Berlin. Inside a neuroscience laboratory in the busy German city, a subject was made to sit on a chair with arms up and bare toes pointed down. Behind the first subject is a second subject, with full access to the first subject's soles. The second subject's mission is simple — to tickle the first subject anytime they want to. As Subject 2 tickled Subject 1, the latter couldn't help but laugh. But when Subject 1 was asked to tickle himself, it was uneventful.
So why can't we help but laugh when we get tickled? And why can't we tickle ourselves? Why our some of our body parts more ticklish than others? These are the questions that humanity have had about tickling. Even the great thinkers and scientists pondered a thing or two about tickling and ticklishness.
"If you read the ancient Greeks, Aristotle was wondering about ticklishness. Also Socrates, Galileo Galilei, and Francis Bacon," says cognitive neuroscientist Konstantina Kilteni. "These questions are very old, and... we still really don't have the answer."
So why can't we tickle ourselves? The leading theory is that a tickle attack from another person is unpredictable, which sends our brain into a mini-frenzy. Meanwhile, a tickle attack from ourselves and to ourselves is predictable. This may be the reason why such scenario would be uneventful.
However, Michael Brecht, the mastermind behind the what I call "Tickle Your Partner" study, has a different theory. He thinks that when a person touches themselves, the brain sends a message throughout the body, which inhibits touch sensitivity. This is why we don't tickle ourselves when we scratch our toes or armpits, Brecht argues.
Learn more details about this fascinating study over at Ars Technica.
(Image Credit: erinmilleravonlady/ Pixabay)