ABSTRACT
Infants acquiring language have to learn about the phonology, the lexicon, and the syntax of their native language. The issue we are going to discuss in the present chapter relates to some of the mechanisms involved in learning a lexicon. A word corresponds to the specifi c pairing between the mental representation of a sound pattern of a word (a word form) and the abstract representation of an object or event in the world that constitutes the meaning associated to that word form (concept). The building of a lexicon then relies on the development of three sets of abilities: (1) to extract, represent with phonetic detail, and store word forms; (2) to build concepts for the objects and events in the world; and (3) to appropriately link word forms and concepts. Note that, although it was long thought that the acquisition of word forms and concepts precedes by several months the acquisition of the fi rst words, recent studies show that all of these abilities emerge around 6 to 12 months of age: phonological acquisition (e.g., Best, McRoberts, & Sithole, 1988; Werker & Tees, 1984a, 1984b), segmentation of word forms ( Jusczyk & Aslin, 1995), learning of concepts (Rakison & Oakes, 2003, for an overview), lexical acquisition (Tincoff & Jusczyk, 1999). This does not mean that these abilities are fully mature by 12 months, but it underlines the importance of studying these different abilities both separately and in their interaction.
