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Why bother laughing?

LuisanaT's picture

Try it. See if you can make yourself guffaw, chuckle, or just giggle. You realize after a few seconds that you can not make yourself genuinely laugh to your hearts content. It is hard to force yourself to burst into tears, be at a short of breathe, and experience sharp pains in your ribs while having a smile spread from ear to ear. It is rather oxymoronic to see a moment of relief that results from hysterical boasts of laughter be accompanied with so much physical strenuous activity. It puts into question the appropriateness of laughter let alone its evolutionary advantage.

Exerting so much energy leads some scientists to believe that laughing is closely related to the flight-or-fight response.(1) When laughing uncontrollably, the brain stem disrupts the normal cyclic breathing patterns of the individual and causes the lungs to accelerate the exchange of residual air, increasing blood oxygen levels throughout the body. This change in respiratory response is similar to hyperventilation causes a sudden increase in metabolism, heart rate, and blood pressure. The adrenal medulla releases adrenaline and other hormones to the body that causes the heart and blood pressure to increase, supporting the diaphragm, abdomen, legs, and creating back muscle spasms. Under much vigorous laughter, salivary immunoglobulin A antibodies, antibody producing B cells, and virus combating T cells increase activity in the mouth.(1) It seems as though mother nature has placed laughter into the human belly to keep the individual on the defensive at all times to survive.

Since all previous attempts to make yourself laugh out loud have failed, maybe tickling yourself will do the trick. Unfortunately, that doesn't seem to work either. The truth is, laughter does not seem to be a solitary act. In the cerebellum, there are touch-induced sensory signals that make it impossible for you to tickle yourself.(1) There are touch receptors on the skin that relay tickle sensations to the part of the brain that is to identify it, called the somatosensory cortex. It is able to sense the varying vulnerabilities throughout the body; the more vulnerable a certain area is, the more ticklish it is.(1)

This makes human beings prone to laughter but only when they are interacting with other human beings.

Laughter seems to function best as a social tool for human beings because is most often expressed within group situations with as few as two people. Laughing together helps to indicate a persons readiness for friendly interaction.(2) Human beings are social creatures that utilize the ability to laugh to sustain favorable relationships within its species. Often times laughter is considered contagious and works as a good icebreaker for people to establish comfortable and safe environments as well as create the social fabric of our world. Here, mother nature is favoring the willingness to cooperate with others to survive.

There seems to be a contradiction in the significance of laughter in humans struggle for existence. What I make from all of this is that as people gradually becomes more interdependent, the function of laughter becomes more important. Back when human beings first walked the Earth, the population was much smaller and with the massive amount of terrain separating them, people were rarely forced to encounter strangers. They all grew independently of one another and did not find the need to form bonds and work together. Instead they always remained sharp, using laughter as a disguise for their fight-or-flight response if ever necessary. It is not until the human population began to expand exponentially, bringing people closer together, were they able to acknowledge the synergy of mankind and laugh together.

Works Cited

(1) Johnson, S. (2003). “Laughter.” Discover Magazine, April 2003, Volume 24, Number 4

(2)“What’s So Funny? Well, Maybe Nothing”

(3) “The Biology of . . . Humor”

(4) “Emotions and the Brain”


Paul Grobstein's picture

the biology of laughter ... together?

Interesting collection of issues. Maybe "laughter", like "life" is an "onion", ie not a single thing with a single definition but instead something with a variety of nested meanings .... and associated physiologies and causes? Yep its hard to tickled onself, but maybe there's a reason for that other than a strict dependence on interpersonal interactions?