Beyond the Input Given: The Child's Role in the Acquisition of Language

The child's creative contribution to the language-acquisition process is potentially most apparent in situations where the linguistic input available to the child is degraded, providing the child with ample opportunity to elaborate upon that input. The children described in this paper are deaf, with hearing losses so severe that they cannot naturally acquire spoken language, and their hearing parents have chosen not to expose them to sign language. Despite their lack of usable linguistic input, these children develop gestural communication systems which share many structural properties with early linguistic systems of young children learning from established language models. This paper reviews our findings on the structural properties of the deaf children's gesture systems and evaluates those properties in the context of data gained from other approaches to the question of the young child's language-making capacity.* This article describes our research program of the past 15 years, which investigates a unique phenomenon in language acquisition-namely, the development of language-like behavior in children who lack normal linguistic input during their early stages of acquisition. The studies encompassed in our research program bear on a number of questions in linguistic and developmental theory, in particular the innate capabilities a child brings to the language-learning situation and the role of parental input in providing sufficient structure for those capabilities to flourish. We discuss our findings and relate them to other studies addressing the child's role in language acquisition. THE CHILD'S CONTRIBUTION TO THE LANGUAGE ACQUISITION PROCESS 1. Linguistic input has an obvious impact on the child's acquisition of language-a child who hears Swahili learns Swahili, not French or Polish. It is equally clear, however, that children (but not dogs, cats, or even chimpanzees; cf. Seidenberg & Petitto 1979) bring certain abilities to the language-learning situation that make language learning possible. A variety of approaches have recently been taken to the task of discovering the child's contribution to the language-learning process. For example, one approach explores the relationship between the linguistic input children receive and their output, in either t [Editor's note: This essay inaugurates a type of Review Article that is new to Language. The editor plans to publish, from time to time, Review Articles that survey an area of linguistic research-a particular research program whose results are likely to interest many readers, as in the present instance, or a widely-discussed topic of current interest. The idea for Review Articles of this type was suggested and discussed at a recent meeting of the editor and several Associate Editors.]