Proceedings of the Annual Meeting of the Cognitive Science Society

One of the major questions in child language acquisition research is whether children and adults have the same mental organization for grammar. We consider the case of the acquisition of -ed and -ing. This has standardly been assumed to show that children organize their grammatical knowledge differently from adults. In contrast to models that claim that children's restriction on these morphemes argues for a noncontinuous view of grammar, we show that it is most parsimoniously accounted for by a privative aspect and tense model (Olsen, 1997), independently needed in the adult grammar. In particular, we show i) that one cannot attribute this pattern of development to children's simple modeling of restrictions in the adult data, and ii) that it is not necessary to assume initial hypotheses discontinuous with the adult state, or primitives not found therein. Rather, the data requires a strong innate component that both delimits possible adult grammars and defines early stages. Our model provides an account of why children show these restrictions, how they recover, and what cross-linguistic variation might occur in the emergence of adult competence.