Bound by Laughter

It’s hard to rival the joy of bursting into peals of laughter with a friend. In primates, grooming helps to build social bonds, and the opioid system is thought to play a part in that process. But for humans, “laughter is faster and it gives us an enhanced opportunity to build large social networks,” says Finnish neuroscientist Lauri Nummenmaa. His team sought evidence that a chemical change takes place when people share a laugh. Using PET scans, they detected shifts in the release of opioid peptides like endorphins—increases in several brain regions as well as some decreases—after a dozen men watched comedy clips with friends. In another study, pain tolerance (linked to the release of opioids) was greater among people who watched a comedy, rather than a drama, in a group. By triggering the release of feel-good chemicals, researchers argue, laughter may inform us that the time is ripe to connect with others and support the deepening of relationships.