First Words: From Theory to Intervention

The purpose of this article is to review research on the acquisition of first words in children who are developing typically, children who are late talkers, and children with developmental delays and compare lexical diversity among these populations. Clinical applications of the research including assessing early vocabularies using parent report instruments, choosing a first vocabulary for children with language delays, and using focused stimulation and milieu teaching during storybook and pretend play activities will be discussed.

Meet Max, a 2.9-year-old boy with receptive and expressive language delays and cognitive delays. The rest of his history is unremarkable. Max has no real, single words. Make a list of the first 10 to 12 words you would target in intervention.

The vocabulary of the first 50 words has long intrigued child language researchers. Initial research in this area used vocabulary diaries and focused on individual children who were developing typically (e.g., Bloom & Lahey, 1978; Nelson, 1973). In more recent years, use of parent-completed vocabulary checklists has allowed researchers to collect data from larger populations of children, with and without language delays, thereby drawing more generalizable conclusions (e.g., Fenson et al., 1994; Lederer, 2006a; Rescorla, Alley, & Christine, 2001). As a result, we now have information on the first words acquired by typically developing children, late talkers, and children with language and cognitive delays. This paper will review the research on first words in each of these three populations and discuss clinical applications of the research to assessment and intervention.

First Words in Children Developing Typically

Much is already known about early vocabulary development in typical children. First words typically appear between 10-16 months. Children learn .81 new words per day before 24 months and typically master 50 words between 18 and 24 months, with 24 months representing the outer limits of normal (Fenson et al., 1994). The average two-year-old has a vocabulary of 200 to 300 words (Owens, 2001). Between 24 and 30 months, children acquire 1.64 new words per day (Fenson et al., 1994).

In terms of lexical diversity, most children are "noun-lovers" (i.e., referential style), which has been attributed to parental labeling. However, a continuum exists between "noun lovers" and "noun leavers" (i.e., expressive style), the latter considered a more peer-influenced style. The vocabularies of noun-lovers appear to grow initially at a faster rate than those of children with more of a balanced lexicon (see Owens, 2001, for a review).