How do the children laugh? Like chimpanzees!


Credit: Public Domain CC0

Few things can delight an adult more easily than the uninhibited and effervescent laugh of a child. Yet, the child's laughter, as a new study demonstrates, differs from adult laughter in a crucial way: children laugh as they exhale and breathe both, in a way that is very similar to non-human primates.

The research will be described by Disa Sauter, psychologist and associate professor at the University of Amsterdam, in the Netherlands, during a speech at the 176th Meeting of the Acoustical Society of America, coinciding with the Canadian Acoustical Association 2018 acoustic week in Canada , November 5-9 at the Victoria Conference Center in Victoria, Canada.

Together with her colleagues, psychologist Mariska Kret and Ph.D. Dianne Venneker of Leiden University in the Netherlands, and Bronwen Evans, a phonetic at the University College of London-Sauter, have studied laughter clips from 44 newborns and infants among 3 and 18 months of age. Recordings were taken from online videos where children were involved in playful interactions. The recordings were then analyzed by 102 listeners, recruited from a student population of psychology, who assessed to what extent the laughter in each clip was produced on expiration with respect to inhalation.

Sauter and his colleagues found that younger children commonly laughed for both inhalation and exhalation, as well as non-human primates such as chimpanzees. In the older children studied, however, laughter was mainly produced only during expiration, as in the case of older children and adults.

Credit: Acoustical Society of America

"Adult humans sometimes laugh by inhalation, but the proportion is quite different from that of the chuckling and childrens' laughter: our results so far suggest that it is a gradual, rather than a sudden change," said Sauter, who emphasizes that the transition does not seem to be linked to particular development goals. He noted, however, that these results were based on the opinions of non-expert listeners. "We are currently monitoring those results against phonetic sentences, which are making detailed annotations of laughter."

Credit: Acoustical Society of America

Sauter said that there is no accepted reason why humans, alone among the primates, laugh only for the exhalation. One possibility, he said, is that it is the result of the vocal control that humans develop while they learn to speak.

Credit: Acoustical Society of America

Researchers are currently examining whether there is a link between the amount of laughs produced by inhalation and exhalation and the reasons why people laugh, which also change with age. In infants and younger children, as in


Please enter your comment!
Please enter your name here

This site uses Akismet to reduce spam. Learn how your comment data is processed.