Science concluded a long time ago (circa 1974) that laughter is contagious. Now we know that women are the best at spreading the joy around. A study from experimental psychologists at Georgia State University concluded that spontaneous, open-mouthed laughter from ladies elicits the most positive emotional responses. Ha!
Study participants listened to around 50 audio clips of various types of laughter, such as open- versus closed-mouthed chuckles, and rated the female belly laugh as the most pleasurable. (And as a female, I can anecdotally attest that belly laughter is definitely the most pleasurable laughter.)
From Discovery News: "The findings suggest that, beginning in childhood, we learn to associate the wide-open guffaw with life's most positive experiences...Eventually, all it takes is to hear that happy sound to feel happier."
Honest-to-goodness laughter might have such a potent effect because it doesn't actually happen very often. Only around 10 percent of our laughter is induced by humor; the rest is just social noise in the form of polite tittering, nervous chortles and other cackling categories. And since we apparently form childhood associations between laughter and positivity that likely trace back to maternal play and interactions, our heightened emotional response to female laughter makes sense.
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