The Scientific Explanation for Ticklishness (2024)

The phenomenon of ticklishness has puzzled scientists and philosophers for decades. From social bonding to survival, researchers have offered a wide range of theories to explain this peculiar bodily quirk.

Opposing Theories

Charles Darwinargued that the mechanism behind ticklishness is similar to the way we laugh in response to a funny joke. In both cases, he contended, one must be “light” state of mind in order to respond with laughter. Sir Francis Bacon made an opposing claim when he said on the subject of tickling,“...[W]e see that men even in a grieved state of mind, yet cannot sometimes forbear laughing." The opposing theories of Darwin and Bacon reflect some of the contemporary conflicts that exist in research on tickling today.

Tickling as Social Bonding

Tickling may function as a form of social bonding, especially for a parent and child. University of Maryland neuroscientist Robert Provine, who considers ticklishness to be “one of the broadest and deepest subjects in science,”says that the laughter response to being tickled is activated within the first few months of life and that tickling as a form of play helps newborns connect with parents.

It's also possible that the horseplay and other games involving tickling help us hone our ability to defend ourselves — a kind of casual combat training. This view is supported by the fact that the regions of the body that happen to be most ticklish, such as the armpits, ribs, and inner thighs, are also areas that are particularly vulnerable to attack.

Tickling as a Reflex

Read MoreMysteries of Biology: DNA, Sounds, and LightningBy Regina Bailey

Research into the physical response to tickling has led to conclusions that conflict with the social bonding hypothesis. The social bonding hypothesis really starts to fall apart when one considers those who find the experience of being tickled unpleasant. A study conducted by psychologists at the University of California in San Diego found that subjects can experience an equal degree of ticklishness regardless of whether they believe they are being tickled by a machine or a human. From these findings,the authors drew the conclusion that being ticklish is more likely a reflex than anything else.

If ticklishness isa reflex, why can’t we tickle ourselves? Even Aristotle asked himself this question. Neuroscientists atUniversity College London used brain mappingto study the impossibility of self-tickling. They determined that the region of the brain responsible for coordinating movements, known as the cerebellum, can read your intentions and even predict exactly where on the body an attempt to self-tickle will occur. This mental process prevents out the intended "tickle" effect.

Types of Ticklishness

Just as there is wide variation to where and the degree in which a person is ticklish, there are more than one type of tickle. Knismesis is the light, gentle tickling felt when someone runs a feather across the surface of the skin. It does not typically induce laughter and can be described as irritating and slightly itchy. Conversely, gargalesis is a more intense sensation triggered by aggressive tickling and usually provokes audible laughter and squirming. Gargalesis is the type of tickling used for play and other social interactions. Scientists speculatethat each type of tickle produces markedly different sensations because the signals are sent through separate nerve pathways.

Ticklish Animals

Humans are not the only animals with a tickle response. Experiments in ratshave shown that tickling rodents can trigger inaudible vocalizations that are akin to laughter. A closer measurement of their brain activity using electrodes even revealed where the rats are most ticklish: along the belly and the bottoms of the feet.

However, the researchers found that the rats who were put in a stressful situation did not have the same response to being tickled, which suggests that Darwin's "light state of mind" theory might not be totally off base. For the human population, the explanation for the tickle response remains elusive, tickling away at our curiosity.

Key Takeaways

  • The phenomenon of ticklishness has not yet been conclusively explained. Multiple theories to explain the phenomenon exist, and research is ongoing.
  • The social bonding theory suggests the tickle response developed to facilitate social bonding between parents and newborns. A similar theory posits that ticklishness is a self-defense instinct.
  • The reflex theory states that the tickle response is a reflex that is not affected by identity of the tickler.
  • There are two different types of "tickle" sensations: knismesis and gargalesis.
  • Other animals experience the tickle response, too. Scientists have found that rats emit an inaudible vocalization akin to laughter when they are tickled.


Bacon, Francis, and Basil Montagu.The Works Of Francis Bacon, Lord Chancellor Of England. Murphy, 1887.

Harris, Christine R., and Nicholas Christenfeld. "Humour, Tickle, And The Darwin-Hecker Hypothesis".Cognition & Emotion, vol 11, no. 1, 1997, pp. 103-110.

Harris, Christine. "The Mystery Of Ticklish Laughter".American Scientist, vol 87, no. 4, 1999, p. 344.

Holmes, Bob."Science: It’S The Tickle Not The Tickler".New Scientist, 1997,

Osterath,Brigitte."Playful rats reveal brain region that drives ticklishness."Nature News, 2016.

​Provine, Robert R. "Laughing, Tickling, And The Evolution Of Speech And Self".Current Directions In Psychological Science, vol 13, no. 6, 2004, pp. 215-218.

The Scientific Explanation for Ticklishness (2024)


The Scientific Explanation for Ticklishness? ›

The somatosensory cortex is responsible for analyzing touch; for example, the pressure associated with it. The signal sent from the skin's sensory receptors also passes through the anterior cingulated cortex, which governs pleasant feelings [source: Blakemore]. Together, these two create the tickle sensation.

What is the science behind being ticklish? ›

The somatosensory cortex is responsible for analyzing touch; for example, the pressure associated with it. The signal sent from the skin's sensory receptors also passes through the anterior cingulated cortex, which governs pleasant feelings [source: Blakemore]. Together, these two create the tickle sensation.

What is the biological reason for being ticklish? ›

Tickling likely serves as a warning signal and training to protect ourselves. It has a secondary feature in humans, other primates, and rats it seems, to facilitate social bonding.

What determines ticklishness? ›

Why some people are more ticklish than others. Some people are physically more sensitive than others, or as Dong puts it: “Everyone has different nerve density.” He adds that genetics could also play a part in ticklishness. Dong does, however, believe you can train yourself to be less ticklish.

What is the physiology of ticklish? ›

Scientists found being tickled stimulates your hypothalamus, the area of the brain in charge of your emotional reactions, and your fight or flight and pain responses.

Is ticklish mental or physical? ›

Ticklishness is a complex physiological response that likely evolved as a protective reflex. While some of the mystery of why we are ticklish remains, the laughter and bonding that often accompany a tickle fight make it a fascinating area of study.

Can you control how ticklish you are? ›

Can you stop yourself from being ticklish? If being ticklish is a reflex, there might not be much a person can do to prevent the sensation. Tickling is more intense when it comes as a surprise, so people could place their hands on those of the tickler to try to reduce ticklishness.

What was tickling originally used for? ›

Tickling was used as a torture by the ancient Romans. Tickling is used in sexual fetishism where it is known as "tickle torture". Research by Dr Sarah-Jayne Blakemore of the Institute of Cognitive Neuroscience in London found that robotic arms used to tickle people are just as effective as human arms.

Why shouldn't you tickle babies' feet? ›

Tickling baby feet can simulate being held down, touched, or violated without consent, which can be highly triggering and traumatic for some children. Even if tickling baby feet is done with good intentions and no harm intended, it can still cause emotional distress and flashbacks.

Is it healthy to be ticklish? ›

Thus, the pleasure or discomfort in response to being tickled may vary. Tickling can be good for your health and well-being if you enjoy it. Some of the benefits of tickling include: Stress management: Tickling generates a sense of well-being.

What is the most ticklish spot on the human body? ›

While the palm of the hand is far more sensitive to touch, most people find that the soles of their feet are the most ticklish. Other commonly ticklish areas include the belly, sides of the torso, underarms, ribs, midriff, neck, back of the knee, thighs, buttocks, nose, feet and perineum.

Why are feet ticklish but not hands? ›

One reason feet are ticklish is that they have more densely packed nerve receptors than most other places on the body. Upwards of 8,000 nerve endings can be found in your foot. This huge amount of nerves makes your feet more sensitive than other body parts, and more ticklish, too.

What happens if you tickle someone too much? ›

Several reported tickling as a type of physical abuse they experienced, and based on these reports it was revealed that abusive tickling is capable of provoking extreme physiological reactions in the victim, such as vomiting, urinary incontinence, and losing consciousness due to inability to breathe.

What is the evolutionary reason for ticklishness? ›

So perhaps, researchers say, tickling is a way to form connections with people. (But this reason doesn't apply to everyone, as some people find tickling painful.) Another idea is that we've evolved to be ticklish as a way to protect vulnerable spots from attack.

What is the biological reason for tickling? ›

One theory is that we evolved ticklish bodies to learn self-defense. The most ticklish places in the body – in between ribs and under the arms, for instance – are also those most vulnerable to physical attack. Perhaps we tickle our children to teach them how to shield those unprotected areas.

What is the neuroscience behind tickling? ›

During a tickle, the skin's nerve endings shoot electrical signals to the somatosensory cortex, a part of the brain that processes touch. Meanwhile, the anterior cingulate cortex analyzes these signals as either harmful or playful. But in the back part of the brain, the cerebellum gives you away.

Can a person stop being ticklish? ›

Although there's limited clinical research on how to stop being ticklish, one technique you might try is this: When you're approached by a person who's planning to tickle you, place your hand on the hand they'll be using for tickling. This action may help suppress your tickle response.


Top Articles
Latest Posts
Article information

Author: Margart Wisoky

Last Updated:

Views: 6221

Rating: 4.8 / 5 (58 voted)

Reviews: 81% of readers found this page helpful

Author information

Name: Margart Wisoky

Birthday: 1993-05-13

Address: 2113 Abernathy Knoll, New Tamerafurt, CT 66893-2169

Phone: +25815234346805

Job: Central Developer

Hobby: Machining, Pottery, Rafting, Cosplaying, Jogging, Taekwondo, Scouting

Introduction: My name is Margart Wisoky, I am a gorgeous, shiny, successful, beautiful, adventurous, excited, pleasant person who loves writing and wants to share my knowledge and understanding with you.