NEGATIVE EVIDENCE ON NEGATIVE EVIDENCE

Previous work has shown that recasts may be contingent responses to ch ildren's early ungrammaticality. On this basis, it has been claimed th at recasts provide negative evidence, thereby offsetting the need for linguistic constraints in theories of acquisition. This study explores whether children exploit negative evidence putatively provided by rec asts by examining whether parental recasts are associated with childre n's recovery from particular overgeneralization errors. Data from long itudinal investigations of 2 common syntactic errors reveal that recas ts are related to children's subsequent grammaticality. However, contr ary to what would be expected if recasts serve as corrections, the dat a show that recasts are negative leading indicators of grammaticality. Finally, correction and negative evidence are examined and are shown to be nonequivalent. Therefore, corrections in whatever form they migh t exist can offset only a limited subset of proposed innate constraint s on language acquisition.