How does laugh happen

In fact, in a study of thousands of examples of laughter, the speakers in a conversation were found to be 46 percent more likely to laugh than the listeners. Young children between the ages of 2.

Evolutionarily speaking, this signal of connection likely played an important role in survival. Upon meeting a stranger, we want to know: What are your intentions with me? And who else are you aligned with? In a study that spanned 24 different societies and included participants, scientists played short sound bites of pairs of people laughing together.

In some cases, the pair were close friends, in others, the pair were strangers. Participants in the study were asked to listen to the simultaneous laughter and determine the level of friendship shared by the laughers.

Using only the sound of the laughter as cues, they could reliably tell the difference between people who had just met and those who were long-time friends. Another theory, which takes the person-to-person connection provided by laughter a step further, is that laughter may be a replacement for the act of grooming each other.

Grooming another is a behavior seen in primates. To groom someone else is a generous, one-sided act. Because it requires trust and investment of time, it bonds the groomer and groomee as friends.

He discovered that all human laughter consists of variations on a basic form that consists of short, vowel-like notes repeated every milliseconds. Laughter can be of the "ha-ha-ha" variety or the "ho-ho-ho" type but not a mixture of both, he says.

Provine also suggests that humans have a "detector" that responds to laughter by triggering other neural circuits in the brain, which, in turn, generates more laughter. This explains why laughter is contagious. Humor researcher Peter Derks describes laughter response as "a really quick, automatic type of behavior. One of the key features of natural laughter is its placement in speech , linguists say. Laughter almost always occurs during pauses at the end of phrases. Experts say this suggests that an orderly process probably neurologically based governs the placement of laughter in speech and gives speech priority access to the single vocalization channel.

This will give a whole new meaning to the phrase:. For more about laughter and the brain, see:. Laughter and the Brain Laughter Different parts of the circuit may be important for: the emotions produced by a funny situation emotional part of humor the "getting it" part of a joke cognitive, thinking part of humor moving the muscles of the face to smile motor part of humor. Is Laughter the Best Medicine? Laughter also: increases blood pressure increases heart rate changes breathing reduces levels of certain neurochemicals catecholamines, hormones.

This will give a whole new meaning to the phrase: "Fun Science" See if I can make you laugh with these brain jokes. Neuroendocrine and stress hormone changes during mirthful laughter. Boiten, F. Autonomic response patterns during voluntary facial action. Ekman, P. Autonomic nervous system activity distinguishes among emotions, Science , , Fried, I.

Electric current stimulates laughter. Nature , , Fry Jr. The physiologic effects of humor, mirth, and laughter. JAMA , , Provine, R. Yoon, C. For instance, how can the sometimes opposite functions of humor, such as promoting social bonding and excluding others with derision, be reconciled?

And when laughter enhances feelings of social connectedness, is that effect a fundamental function of the laughter or a mere by-product of some other primary role much as eating with people has undeniable social value even though eating is primarily motivated by the need for nourishment?

There is much evidence for a fundamental function. Robert Provine of the University of Maryland, Baltimore County, showed in Current Directions in Psychological Science, for example, that individuals laugh 30 times more in the company of others than they do alone.

In his research, he and his students surreptitiously observed spontaneous laughter as people went about their business in settings ranging from the student union to shopping malls.

Moreover, humor does not always make us laugh. In one view, knowing how to be funny is a sign of a healthy brain and of good genes, and consequently it attracts partners.

Researchers have found that men are more likely to be funny and women are more likely to appreciate a good sense of humor, which is to say that men compete for attention and women do the choosing.

But views, of course, differ on this point. Even the validity of seeking a unified theory of humor is debated. In fact, I always refer to it by describing it, never by defining it. Still, certain commonalities are now accepted by almost all scholars who study humor. One, Forabosco notes, is a cognitive element: perception of incongruity.

To my mind, for example, the incongruity needs to be relieved without being totally resolved; it must remain ambiguous, something strange that is never fully explained.

Other cognitive and psychological elements can also provide some punch. These, Forabosco says, include features such as aggression, sexuality, sadism and cynicism. Laughing, Tickling, and the Evolution of Speech and Self.

Robert R. Peter McGraw et al. Christian Jarrett in The Psychologist, Vol. Giovanni Sabato trained as a biologist and is now a freelance science writer based in Rome. Beyond psychology, biology and medicine, he is interested in the links between science and human rights. Already a subscriber? Sign in. Thanks for reading Scientific American.

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