Children creating language: How Nicaraguan sign language acquired a spatial grammar

It has long been postulated that language is not purely learned, but arises from an interaction between environmental exposure and innate abilities. T he innate component becomes more evident in rare situations in which the en vironment is markedly impoverished. The present study investigated the lang uage production of a generation of deaf Nicaraguans who had not been expose d to a developed language. We examined the changing use of early linguistic structures (specifically, spatial modulations) in a sign language that has emerged since the Nicaraguan group first came together. In under two decad es, sequential cohorts of learners systematized the grammar of this new sig n language. We examined whether the systematicity being added to the langua ge stems from children or adults: our results indicate that such changes or iginate in children aged 10 and younger. Thus, sequential cohorts of intera cting young children collectively possess the capacity not only to learn, b ut also to create, language.