Asked by: Alex Cooksley, Coventry
Human laughter is unique, although monkeys and apes ‘giggle’ when tickled and many animals pant when playing. The noise signals playtime and laughter lowers heart rate and blood pressure. Laughing with others maintains social bonding and shows everyone they’re having fun instead of being serious. That can make giggling infectious and the infection can get out of control, hence ‘the giggles’.
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