by Zoë Pollock
Robert Provine pioneered the field of laugh science:
In his lab, Provine feeds the laughter into a sound spectrograph, analyzing the frequency, amplitude, and length of each sample. In more than 30 years of fieldwork he’s collected an astounding amount of data. He knows that “laugh notes” (such as “ha,” “ho,” or “heh”) have a duration of 75 milliseconds, separated at regular intervals of 210 milliseconds. He’s found that babies laugh 300 times a day, while adults laugh only 20 times. And he knows that laughter peaks at around five years of age.
The most important discovery may be the most obvious, that laughter creates social bonds:
It explained why people laugh 30 times more often in the presence of others than they do when they’re alone. It also explained why nitrous oxide (a.k.a. laughing gas) won’t crack you up when inhaled in solitude.
The Dish 