The Onset of Language Language Acquisition Data

While there are numerous definitions of language disorders, most state, in one form or another, that such disorders are deviations from normal language expectations. These definitions implicitly require knowledge of normal language behavior in order that valid judgments can be made about pathological language. Since, among other factors, linguistic "normalcy" is a function of age, the topic of language disorders must be viewed from a developmental framework. Although a substantial number of language pathologists have articulated a recognition of the importance of language acquisition data to the diagnosis and management of language disorders, few have attempted to transfer recognition into specific application. Even worse, many language pathologists have approached their missions with little contemporary information on language acquisition. This situation is related, in part, to the abundance of language acquisition research being done in disciplines outside of speech and language pathology, especially in linguistics, psycholinguistics, and sociolinguistics. As stated elsewhere in this book, linguists are interested in writing theoretical grammars for an idealized language system which will account for all grammatical and novel sentences of a language. Psycholinguists are interested in determining the psychological principles which permit human beings to do such things as acquire, comprehend, produce, store, and perceive a language. Sociolinguists are interested in the interaction between language and culture and, therefore, in the nature and history of linguistic variations within a specified sociocultural setting. Before presenting the status of research and theory on the acquisition of American English, it should be noted that the topic has almost always been approached from the context of the vocalizations of white, middle-class children. The importance of this point is obvious in light of contemporary sociolinguistic theory which supports the legitimacy of all variations (dialects) of American English. These dialects, which result from the history and culture of their speakers, are realized as identifiable ethnic, regional, and social markings on the English language. Thus, if one is to make valid judgments about linguistic pathologies in children, the judgments must be made in the context of the language system of the child's linguistic community.