The Science Behind Why Do We Laugh When Tickled?

by Shreya Patro September 04, 2022

Know Why Tickling Triggers Laughing

We often find jokes funny and roll on the floor. You might have also seen how different people react differently to the same joke. Similarly, a person laughs hysterically when tickled. Some may not be responding in the same way but will show the same result.  Laughing is the common response to tickling. Why do we laugh when tickled? Why don’t we cry or shout?


Are we the only animals that can laugh? No, there are 65 species according to our knowledge that can show laughing as a response. You will be surprised to know that hyenas actually don’t laugh. Their vocal response means something else. Let us learn what tickling is first and then proceed to find out why the common response to it is laughing.


What do you mean by Tickling?

Aristotle, in 350 BC, explained that only humans are susceptible to tickling because our skin is finer than the rest of the animals. Moreover, we are the only creatures that can laugh. Well, this is not true actually as researchers have found 65 different species that use laughter as a response.


In this aspect, let us find out what tickling is. It is a complex sensation when something is intentionally moved on your skin mildly or someone approaches the particular places of your body when you are in a vulnerable position for fun. It means you know that a person is not going to harm you but rather wants to give you a little discomfort in some sensitive places. It is called tickling.


The response to tickling can be different for different people. It all depends on the state of mind. If someone is happy, he will respond by laughing hysterically. If someone is having a bad day, he might not be responding in a pretty way. For instance, armpit tickling can make you laugh but someone may feel irritated considering his sensory reception and state of mind.


Types of Tickling

There are different kinds of tickles based on the depth and pressure of touch using objects or organs.


1. Gargalesis

This is the heavier version of tickling where fingers are used to touch the sensory regions such as the underarms, neck, belly, feet, etc to promote laughing. For example, when feet tickling is done, a person will laugh even if he does not want to. We can witness an ape laughing when its feet are tickled.

2. Knismesis

In the same context, simply touching your skin with objects or fingers is called knismesis. It is the lighter version of tickling resembling a feather touching your skin. This light touch can be responded to in different ways and laughing is one of them. It happens to common mammals.


The Science behind Tickling

Now that we know the tickle meaning, we need to understand the scientific reason behind its triggering.


When someone is tickled, his brain analyses the touch as a receptive message. The effect of tickling, light or heavy, is analysed and results in laughing or showing distress. It is analysed in two different sections of our brain.


The Somatosensory Cortex analyses the depth and location of the touch. A signal is also sent to the sensory receptors of skin in the Anterior Cingulate Cortex of our brain. This part of the brain governs feelings related to pleasure. Both these sections of our brain analyse the touching sensation and simulate laughing when tickled.


When tickled heavily, it can go from a pleasure level to a distress level. Many researchers also suggest that laughing is an auto-response that can be correlated to distress. You laugh when your body is in distress. It also occurs when you know that a person is approaching you to tickle you and you are not in danger.


For instance, when a spider is crawling on your skin without your knowledge, it will trigger a protective response. You will jump or immediately remove that spider from your skin. If you know that a person is tickling you with a feather, your response will be entirely different.


In the same context, the location of tickling also causes different sensations and the level of response. For instance, we will laugh hysterically when our feet are tickled. It is a sign of distress. When head tickling is done, we will show signs of pleasure rather than distress.


Tickling Causes Laughing


Tickling Causes Laughing


How to Tickle Someone?

Tickling someone is easy but needs to be calculative. We have specific sensory regions that are more sensitive than the rest of our bodies. These regions such as the neck, armpits, feet, belly, etc are sensitive to tickling.


You can use your fingers to tickle someone. Simply, adding a little pressure while running your fingers on these parts of a person’s body will cause tickling. If a person cannot run from this situation, he or she will start laughing as an automatic response to this distressing situation. When the pressure applied is more, the recipient will not find out how to control laughter. However, it is important to practise caution in order to not cause injury to any person since the response of the person tends to be uncontrollable.


Tickling, at first, can be surprising. The recipient will be startled, surprised and will be alarmed. When he knows that someone known is tickling and there is no harm, his or her brain  will then process it in a neutral or non-aggressive way. The response becomes laughing.


Tickling is a Distress Response!

Now we know why do we laugh when tickled. The science behind tickling is explained by neuroscientists and psychologists. Tickling is a type of distress to our skin in sensitive areas. We respond in a non-lethal or non-aggressive way when someone is tickling us. The degree of laughing depends on the uncontrollable sensation of our skin. Our emotional degree of tickling pressure and the level of sensation a person feels. It is a harmless response to show that we have a surreal response to such vulnerability is laughing.