The type, but not the amount, of information available influences toddlers' fast mapping and retention of new words.

PURPOSE: The authors of this study examined whether the type and number of word-learning cues affect how children infer and retain word-meaning mappings and whether the use of these cues changes with age. METHOD: Forty-eight 18- to 36-month-old children with typical language participated in a fast-mapping task in which 6 novel words were presented with 3 types of cues to the words' referents, either singly or in pairs. One day later, children were tested for retention of the novel words. RESULTS: By 24 months of age, children correctly inferred the referents of the novel words at a significant level. Children retained the meanings of words at a significant rate by 30 months of age. Children retained the first 3 of the 6 word-meaning mappings by 24 months of age. For both fast mapping and retention, the efficacy of different cue types changed with development, but children were equally successful whether the novel words were presented with 1 or 2 cues. CONCLUSION: The type of information available to children at fast mapping affects their ability to both form and retain word-meaning associations. Providing children with more information in the form of paired cues had no effect on either fast mapping or retention.

The development of language and literacy: evaluating the stereotypes.

People hold many stereotypes about the development of language and reading. We review current data concerning three stereotypes: (1) Girls learn language faster than boys; (2) Biological factors determine the time course of language acquisition; and (3) Dyslexia is a visual problem involving the reversal of letters. In each case, recent data leads to a different picture of the acquisition of language and literacy and deepens our understanding of the processes involved.

Does frequency count? Parental input and the acquisition of vocabulary.

Studies examining factors that influence when words are learned typically investigate one lexical category or a small set of words. We provide the first evaluation of the relation between input frequency and age of acquisition for a large sample of words. The MacArthur-Bates Communicative Development Inventory provides norming data on age of acquisition for 562 individual words collected from the parents of children aged 0 ; 8 to 2 ; 6. The CHILDES database provides estimates of frequency with which parents use these words with their children (age: 0 ; 7-7 ; 5; mean age: 36 months). For production, across all words higher parental frequency is associated with later acquisition. Within lexical categories, however, higher frequency is related to earlier acquisition. For comprehension, parental frequency correlates significantly with the age of acquisition only for common nouns. Frequency effects change with development. Thus, frequency impacts vocabulary acquisition in a complex interaction with category, modality and developmental stage.