The act of tickling is perhaps one of the silliest actions undertaken by an intelligent species such as us humans. Tickles are mostly associated with the memories of childhood, being comfortable and being in the vicinity of people who are emotionally close to us – like family and friends. In the modern world, tickling a person is a way to amuse someone and form a happy memory since both the parties involved are laughing.
However, it is odd to think there is a physical action – apparently having no function – which can make a person laugh. The reason behind the phenomena of tickles has been researched upon since the times of Aristotle (350 BCE) and has been awed by Charles Darwin (1872). It was proven long before that the human body does not pave the way for a redundant action. So, what is the purpose of being ticklish?
What is a tickle?
A TICKLE is a response generated when a sensitive part – such as the stomach, armpits or feet – of a person is touched and they feel an urge to laugh. Tickling is the act of producing a tickle. While the basis of getting tickled is to do with the psychology and mood of the person, most of the people have been tickled and laughed due to it. Some people may be so sensitive to tickling that the mere anticipation of getting tickles would result in them laughing.
There are two types of tickling generally experiences – KNISMESIS and GARGALESIS. Knismesis refers to a light form of tickling on a sensitive part of one’s body, which triggers an urge to get rid of it. The best-demonstrated example of the feeling of knismesis is a bug walking on our arm or when a feather is brushed against our feet.
Gargalesis is a much intense form of ticking which causes an elaborate reaction – laughter. This is triggered when someone touches one of the sensitive parts (as mentioned above) repeatedly. Gargalesis is the traditionally known form of tickling. Another major difference between knismesis and gargalesis is the ability of the person to tickle themselves – one can move a feather on their body and feel the tickle, but gargalesis cannot be subjected to our own.
Why do we get tickled?
The response to tickling is purely psychological. The foremost theory of why we laugh when tickled was that it was a DEFENCE MECHANISM. A defense mechanism is triggered if there is a sudden touch – which one can perceive as an attack – by another person. Evidence backing this theory up is that we cannot tickle ourselves. When we tickle ourselves, the brain does not assume this as an ‘attack’ and does not initiate the defense (laughter).
Due to the happy memories formed during the act of tickling, scientists have associated it with social bonding. The common conception in play here is that only a person who we are comfortable with can touch us at such vulnerable spots – thereby, strengthening an existing social bond.
Laughter is the predominant trait associated with tickling. However, some people incur a slight pain while being tickled and do not laugh. The laughter is an oddity, especially if one assumes it to be a defense mechanism. This lets scientists ponder whether laughing – as a reaction to being tickled – is a learned trait. A learned trait is one a person inculcates by mimicking someone – such as a family member or a close friend or a role model.
It was discovered that children first start responding to the sensation of being tickled around the age of 6 months – which is two months after they learn to laugh. The scientist imagined a scenario of an infant being tickled while the person tickling them is also laughing. This would stimulate the infant’s brain to perceive it as harmless (since they are mimicking the person) and begin to laugh as well. As this practice continues, the infant’s reaction to tickling has been ingrained in their brain as being a burst of laughter.
Why do we laugh when tickled?
Laughter has never been a defense mechanism on its own – perhaps in the case of tickles, it may be. To test this, MRI scans of brains of people being tickled were studied. The scans highlighted that the activity of the HYPOTHALAMUS peaked during such an event. This phenomenon was thus linked to the FIGHT OR FLIGHT RESPONSE, one of the premium defense mechanisms in the body.
When a person faces danger, the hypothalamus in their brain signals the ADRENAL GLAND to release the hormone EPINEPHRIN (also called adrenaline) which determined whether the individual would fight the danger or run for their life. Since the hypothalamus was activated when the people were being tickled, it was presumed to be another form of the fight or flight response. The hypothalamus – instead of releasing adrenaline – signals for an emotional response, which manifests as laughter.
Logically, the body parts sensitive to tickles are also the ones highly susceptible to a physical attack – especially the stomach. The stomach is also the part that is the most sensitive since it does not have bones to protect it. While such a reason cannot be attributed to all the body parts which are ticklish – like the underarms and the feet – scientists have deduced to be a play of the individual’s hypothalamus and what they perceive danger to be.
Can someone choose to be not ticklish?
Since everyone’s brains are unique, some people are unaffected by tickling – such people are assumed to not be ticklish. Some are also known to have overcome the trait by conditioning their mind and for many, the response depends entirely on their mood. As expected, since tickling is a fun activity, a person has the most chances of being ticklish when they are happy and close to none when serious. To master the trait of not laughing, people have stayed calm when being tickled, which keeps the hypothalamus at bay and hindering the fight or flight response. This technique may not work for many and depends entirely on the sensitivity of the individual.
Regardless of the speculation of being tickled as being an evolutionary defense mechanism, it is a bonding moment in modern times. Most people marvel at the silliness of the act but also appreciate the emotional connection formed between them. It is also crucial to understand when a person must stop – a keen observation is that people who are highly sensitive to tickling when it starts to hurt the person, are the ones uncomfortable with physical touch or intimacy. Being aware of this helps us to become a morally driven person with boundaries.