Most languages have a word that that serves as interjection for expressing pain. In Mandarin, it’s “ai-yo.” In French, it’s “aïe.” And in several Indigenous Australian languages, it’s “yakayi.” All have sound elements that seem quite similar—and that’s no coincidence, according to a new study in the Journal of the Acoustical Society of America. Researchers found pain interjections are more likely to contain the vowel sound “ah” (written as [a] in the International Phonetic Alphabet, or IPA) and vowel combinations that use it, such as “ow” and “ai.” These findings may point back to the origins of human language itself.