Researchers at the University of Amsterdam have dedicated their latest study to the unique laughter that arises from tickling. Indeed, it differs from any other type of laughter. The scientists aimed to uncover what lies at its core.
In the first phase of the study, the team asked around 200 volunteers to listen to recordings of various types of laughter and identify what triggered it in each case. Among the options presented, in addition to laughter from tickling, were giggles in response to a funny situation, laughter at someone else’s misfortune, and laughter at a joke. Participants were able to identify tickle-induced laughter with about 60 percent accuracy.
The second experiment involved listening to and analyzing 887 YouTube videos. As a result, participants noted that laughter from tickling is characterized by less vocal control compared to other types of laughter. Volunteers also rated it as more spontaneous, according to the Daily Mail.
What Conclusions Did the Scientists Reach?
The team reminded us that tickling is an ancient evolutionary play behavior. In an article published in the journal Biology Letters, the researchers wrote: “Laughter has deep evolutionary roots: many mammals, including chimpanzees, squirrel monkeys, and dogs, produce sounds similar to laughter during play.”
Meanwhile, human laughter is “one of the first complex expressions of social behavior: infants begin to laugh just a few weeks after birth.”
According to the researchers, laughter is “ubiquitous in human life, yet the reasons for its occurrence and variations in sound differ greatly.”
The team believes that the participants’ relatively accurate identification of tickle-induced laughter confirms that this type of laughter is distinct not only acoustically but also perceptually. The scientists suggest that the heightened excitement observed during tickling laughter implies it is an “automatic response” to a stimulus.
In the researchers’ view, laughter triggered by tickling may serve as a protective mechanism.
They explained: we laugh when we are tickled because the part of the brain that prompts us to laugh at light touches (the hypothalamus) signals the need to anticipate painful sensations.
Previous studies have shown that laughter evolved in humans as a way to diffuse tense situations and protect themselves from danger.