Continuity and Variation in Early Language Development

The study of language acquisition in normal children began in earnest in the 1960s. ¹ Linguists and psycholinguists committed to this new enterprise set out in search of orderly sequences or stages through which normal children pass enroute to adult language. A major goal was to identify universals that would characterize the language acquisition process for all children and all languages. In the last 20 years studies have successfully documented some regularity in development of phonology, morphology, syntax, and semantics. However, substantial diversity has also been found. Some of this variation appears to be a product of the structural differences among natural languages (e.g., English children acquire word-order regularities before they acquire grammatical morphology, whereas Turkish children show the opposite pattern; see Bates & Marchman, 1987; Slobin, 1985). But differences among individual children from the same language group have also become increasingly apparent, and these pose a substantial challenge to models of language acquisition that grew out of the search for universals. The most important challenges come under three headings: innateness, domain specificity, and normality.