The Science Of Laughter

Laughter: An ancient vocal signal older than language, shared with great apes, that mostly functions as social glue; people laugh far more often in company than alone, and usually at ordinary remarks rather than jokes.

Robert Provine: After recording more than 1,200 real conversations, he found that only a small fraction of laughs followed anything resembling a joke, and that speakers laugh more than their listeners.

Marina Davila-Ross: By tickling infant apes and humans and comparing the sounds, her team traced laughter back to a common ancestor that lived roughly 10 to 16 million years ago.

Jaak Panksepp: The neuroscientist discovered that rats emit ultrasonic 50 kHz chirps when tickled, chase the hand that tickles them and seem to experience a form of laughter.

Tanganyika Laughter Epidemic: In 1962 uncontrollable laughing spread from a girls' boarding school in Kashasha to surrounding villages, affecting about 1,000 people and forcing over a dozen schools to close.

Charley Douglass: The sound engineer invented the 'Laff Box,' a secret keyboard-like machine of recorded laughs that gave TV its laugh track; he guarded its contents so closely that few people ever saw inside.

Sophie Scott: The UCL neuroscientist showed that simply hearing laughter primes the brain regions that move our face, which helps explain why it is so contagious, and that listeners can reliably tell real laughs from fake ones.

Guillaume Duchenne: In the 1860s this French neurologist electrically stimulated faces and found that a genuine smile engages the muscles around the eyes, now known as the 'Duchenne smile.'

Itzhak Fried: In 1998 his team stimulated a spot in a patient's brain and triggered laughter; she explained it by saying the doctors looked funny, showing the brain invents reasons for laughs after the fact.

Sarah-Jayne Blakemore: Her research explained why you can't tickle yourself: the cerebellum predicts the sensation of your own movement and cancels the surprise.

Robin Dunbar: His experiments found that people who laughed together at comedy tolerated more pain afterward, suggesting laughter releases endorphins and works like 'grooming at a distance' for large groups.

Gregory Bryant: His 2016 study found that listeners across 24 societies could tell from just one second of shared laughter whether the people laughing were friends or strangers.

Laura Kurtz: Her research found that couples who laugh together, not just laugh a lot, report feeling closer and more satisfied in their relationships.

Madan Kataria: The Mumbai doctor started Laughter Yoga in 1995 with a handful of people in a public park, laughing on purpose with no jokes; it has since spread to thousands of clubs worldwide.

Norman Cousins: The editor's 1979 book 'Anatomy of an Illness' described watching Marx Brothers films and reporting that ten minutes of belly laughter gave him two hours of pain-free sleep, sparking research into laughter and health.

Gelotophobia: The fear of being laughed at, studied by psychologist Willibald Ruch, shows laughter's dark side; people with it often cannot distinguish friendly teasing from ridicule.

Thomas Hobbes: The philosopher's 'superiority theory' called laughter a 'sudden glory' at feeling above someone else, an idea that still explains a lot of mockery and slapstick.

Immanuel Kant: He proposed that laughter comes from 'a strained expectation being suddenly reduced to nothing,' an early version of the incongruity theory behind most punchlines.

Sigmund Freud: In his 1905 book on jokes, he argued laughter releases pent-up nervous energy from forbidden thoughts, which is why taboo humor can feel so explosive.

Plato: In 'The Republic' he warned against violent laughter and argued that the guardians of his ideal state should not be given to it, one of history's earliest suspicions of humor.

Sumer: The oldest recorded joke, from around 1900 BC, is a Sumerian proverb about flatulence, proof that toilet humor is as old as writing.

Philogelos: The oldest surviving joke book, written in Greek around the 4th century AD, contains 265 jokes, including gags about absent-minded professors that still resemble modern ones.

LaughLab: Psychologist Richard Wiseman's 2002 online experiment gathered about 40,000 jokes and millions of ratings to find the world's funniest joke, which turned out to be about two hunters.

OKeh Laughing Record: A 1922 recording in which a cornet solo keeps collapsing into giggles became a huge hit, with listeners buying it just to laugh along, early proof that laughter spreads by sound alone.

Patricia Simonet: She recorded a breathy 'play-pant' that dogs make during play and reported that playing it in animal shelters appeared to calm stressed dogs, suggesting other species have their own laughter.