Why can't you tickle yourself?

2025-05-31 21:54:00, Kuriozitete CNA

The inability to tickle oneself is a strange phenomenon that has puzzled many people, including brilliant minds like Socrates, Aristotle, and Charles Darwin.

Neuroscientist Konstantina Kilteni argues in a scientific article published this month in Science Advances that we should take tickling research more seriously.

“Tickle is relatively understudied,” says Kilten, who runs a tickle lab at Radboud University in the Netherlands. “It’s a complex interplay of motor, social, neurological, developmental, and evolutionary aspects. If we know how tickle works at the brain level, that could provide a lot of insight into other topics in neuroscience.”

Tickling can strengthen the bond between parents and children, for example, and we commonly tickle our babies and children.

But how does the brain process tickling stimuli and what is the relationship with the development of the nervous system?

By investigating this, you can learn more about brain development in children. The fact that you can't tickle yourself is also interesting from a scientific perspective.

"Apparently, our brains distinguish us from others, and because we know when and where we will tickle ourselves, the brain can deactivate the tickling reflex in advance. But we don't know exactly what happens in our brains when we are tickled," explains Kilten, according to a press release from Radboud University.

One of the fundamental aspects of tickling is the element of surprise. When someone else tickles you, you can't predict the exact timing, pressure, or location of their touch. This unpredictability takes your nervous system by surprise, producing the tickling sensation and often eliciting laughter.

“Gargle” is a unique type of tickling, specifically the type that elicits a laughing response, and is often described as “hard tickling.” It is characterized by more intense tickling sensations, involving repeated touching or pressure on sensitive areas, often resulting in uncontrollable laughter and giggles. This type of tickling is usually experienced when someone else tickles you; it is not usually possible to tickle yourself in a way that produces a gargle.

According to the study, Kilten says the scientific understanding of tickling is "extremely weak." She says we still don't know why some areas of the body are more sensitive to tickling than others, and why some people like being tickled while others don't. "The primary function of tickling in humans, as well as in other species, remains a big mystery," she says.

Research also shows that people with autism spectrum disorder, for example, perceive touch as more itchy than people without the disorder. Investigating this difference could provide clues about changes in the brains of people with autism spectrum disorder.

“But we also know that apes like bonobos and gorillas respond to touch that causes itching, and even mice have been observed to do so. From an evolutionary perspective, what is the purpose of scratching? What do we gain from it?” asks Kilten. No one knows why our armpits and the soles of our feet are considered the itchiest areas. They don’t have the thinnest skin or the highest concentration of nerve endings, the study says. And from an evolutionary or survival perspective, scientists haven’t figured out why these two areas might cause the greatest itch sensations./ CNA