Tickling

What is tickling?

Tickling is touching the skin in a way that triggers an involuntary laugh reflex and an urge to pull away. Science distinguishes two kinds: a light, itchy touch, and the firm, rhythmic variant that you can manage on someone else but not on yourself.

How tickle play works in practice

Almost always with something that makes pulling away impossible.

Tickling without restraint lasts two seconds, because the body turns away on its own. Lock the wrists or the ankles and that escape disappears, and a touch that means nothing by itself becomes something that seems to have no end. So the build-up is bondage first, then the agreement about stopping, and only after that the feathers or the fingers.

A typical scene looks like this. Someone lies restrained, bare on the spots that matter according to the research, and the other starts light and slow. After a minute the character changes: the laughter goes higher, the breath shorter, and the request to stop comes out between two fits of laughter. That moment is the whole game, and also the moment when you need to know what the two of you agreed.

There is not much variation: light with a feather or brush, hard with fingers, or blindfolded so you don’t know where the next touch will land.

Why you can’t tickle yourself

Because your brain has already announced your own hand before it arrives.

Konstantina Kilteni of the Donders Institute in Nijmegen sets the two sensations side by side in her review article in Science Advances. Knismesis is the light, feather-like touch that works anywhere on the body, feels itchy and can largely be produced on yourself. Gargalesis is the faster, firmer touch on the trunk, the armpits and the soles that leads to laughter, and that one you cannot manage on yourself. The common explanation is that the brain predicts the sensory consequences of your own movements and therefore suppresses them.

Proelss and colleagues put that into measurable figures in Philosophical Transactions of the Royal Society B. Facial expression and chest circumference change about 300 milliseconds after the first touch, the sound follows some 200 milliseconds later, and the faster, louder and higher someone laughs, the more ticklish they call it afterwards. Their finding with the most practical value: touching yourself at the same time dampens what the other does, more strongly than only making the same movement.

That same group cites the ranking G. Stanley Hall and Arthur Allin wrote down in 1897: the sole of the foot at the top, then the armpit, the neck and the chin.

Where the word comes from

From the same Germanic root, and it is nearly eight hundred years old.

The English tickle and its variant kittle share a root with the Dutch kitelen. The Etymological Dictionary of Dutch gives the oldest attestation as 1240, in the sense “to prickle pleasantly”. Half a century later it already appears described in practice: “ende kitelde … onder die vute”. The side form kittelen turns up in 1494. Related are the Old High German kizzilōn and the English kittle, and it is probably a sound-expressive formation within Germanic: the word sounds like what it does.

Why people enjoy tickling

For the helplessness, not for the feeling on the skin.

Tickling is one of the few things where your body does something you did not decide and cannot hold back either. For anyone who likes losing control, that is a shorter route than pain, and no object is involved. For the person tickling, the appeal is in the immediacy: within half a second you see exactly what your touch does.

Kilteni herself cites figures showing that only about a third of the people studied enjoy being tickled; a third are neutral and well over a third distinctly dislike it. So someone who laughs hard can perfectly well belong to that last group.

Misunderstandings about tickling

“Whoever laughs enjoys it.” No. Kilteni writes in so many words that it stays unclear whether we laugh because we enjoy it, and Hall and Allin already described the reaction in 1897 as stiffening, pulling away, smiling and laughing all at once. With tickling, laughter is a reflex, not a judgement, and therefore not consent either.

“Tickle torture is an old punishment from Roman times.” There is nothing to back that up in the scientific literature. The most recent review article names one single case from all of history, with a memoir about the German camps in the Second World War as its source. The Roman goats and Chinese dynasties you run into online appear nowhere in it.

“Tickling isn’t a real subject.” Socrates, Aristotle, Erasmus, Bacon, Galileo, Descartes and Darwin all wrote about it, and yet according to Kilteni, after two thousand years there has still been barely any experimental work. Small subject, but not solved.

“Tickling and knismolagnia are the same thing.” Tickling is the act; knismolagnia is the arousal some people take from it, a fetish with its own literature and its own row in the A-Z list.

What I see of it myself

Tickling rarely comes to me as a request and often as a by-catch. Someone lies restrained for something else, I brush past somewhere, and there turns out to be a reaction neither of us counted on.

The turning point comes sooner than people think and is hard to read from the outside. Laughter stays laughter, even when it is no longer fun. With whips I read it off the breathing and the shoulders, but with tickling the body is already doing all those things anyway. That is why this is the only kind of play where I agree a hand signal beforehand instead of a word.

What you can do yourself

• Agree a non-verbal stop sign before you start. With tickling someone can’t get a word out, so a fist that opens or snapping the fingers twice works better than a word. Agree it the way you agree a check-in.
• Set a clock. Without an end point this game always slides on past the point where it was fun.
• Start at the neck or the side and save the soles for later. According to Hall and Allin that is the most sensitive spot of all.
• Stop at tears or someone gasping for breath. Prolonged tickling can turn the laughter into crying, and that is not a phase you push through.
• Hold back if someone is breathing with difficulty. The first measurable reaction to tickling is a change in chest circumference, and being restrained removes the only escape.
• Talk afterwards. Anyone who didn’t enjoy it says so more easily afterwards than during, because during it sounded like laughter.

More reading about tickling

On this site the article on the art of bondage is about the restraint that makes tickle play into anything at all, and the piece on the safeword is about why the agreement to stop weighs heavier here than the act.

Beyond this site, the review article by Kilteni in Science Advances is the best way in, even without a background in neuroscience. If you would rather see measured values, Proelss and colleagues give the reaction times and the sound analysis.

Where this fits on this site

Tickling is on none of my lists, bondage is. The page about the BDSM date shows how we decide beforehand what happens and where it stops, and with this act that conversation matters more than with almost anything.

Sources

• The extraordinary enigma of ordinary tickle behavior: Why gargalesis still puzzles neuroscience. Konstantina Kilteni, Science Advances 11(21), 2025. Provides the distinction between knismesis (light, feather-like touch, anywhere on the body, largely self-inducible) and gargalesis (fast, firm touch on trunk, armpits and soles, not self-inducible), the finding that it stays unclear whether we laugh because we enjoy it, the line of thinkers from Socrates to Darwin who wrote about it, the figures in which 32 percent of 84 subjects enjoy it, 32 percent are neutral and 34 percent do not enjoy it, the observation that prolonged tickling can turn laughter into crying, and the only historical reference to tickling as punishment or torture in the Second World War, with a memoir as its source.
• The human tickle response and mechanisms of self-tickle suppression. Proelss, Ishiyama, Maier, Schultze-Kraft and Brecht, Philosophical Transactions of the Royal Society B 377(1863), 2022. Provides the reaction latency of roughly 300 milliseconds for facial expression and chest circumference with the vocal reaction some 200 milliseconds later, the link between the speed, loudness and pitch of the laughter and the self-reported ticklishness, the finding that simultaneous self-touch dampens the externally induced tickle sensation and that touching dampens more strongly than the movement alone, and the ranking of Hall and Allin from 1897 with the sole of the foot at the top, followed by armpit, neck and chin.
• kietelen. Etymologiebank, hosted by the Dutch Language Institute, with the entry from the Etymological Dictionary of Dutch (Philippa et al., 2003-2009) and that of De Vries (1971). Provides the Middle Dutch form kitelen in the sense “to prickle pleasantly” from 1240, the attestation “ende kitelde … onder die vute” from 1290-1310, the side form kittelen from 1494, the Germanic cognates kitilon, kizzilōn, kitla and the English kittle, and the finding that it is probably a sound-expressive word formation within Germanic.

Related terms

• Sensation play. The umbrella that tickling is the lightest form of.
• Bondage. The restraint that turns tickling from a nudge into a scene.
• Check-in. The traffic-light system, and the reason you agree a hand signal for tickling.
• Hard limit. Where you put this subject if it is nothing for you.
• Blindfold. The addition that makes the touch unpredictable.
• Ice cubes. The other sensory stimulus that costs little and does a lot.