A naturalistic study of early lexical development: General processes and inter-individual variations in French children

Abstract

This study investigated early lexical development in French by analysing changes and variability in lexical production and composition of children’s spontaneous speech samples from three age groups: 1;8, 2;6 and 3;3 years (20 children in each). Analyses of general developmental changes showed that lexical productivity increased strongly between 1;8 and 2;6 and between 2;6 and 3;3. Changes in lexical composition mostly occurred between 1;8 and 2;6, indicating that the most important reorganizations are achieved by 2;6. The main changes observed (decreases in proportions of nouns and paralexical classes, and increases in proportions of predicate and grammatical classes) fit overall the developmental trajectories found for other languages, such as English and Italian. Two controversial issues were particularly examined and discussed with regard to cognitive, language-specific and methodological factors: noun-verb asynchrony and grammatical word explosion. Quantitative individual differences in lexical composition were greater at 1;8 than at 2;6 and 3;3, supporting the hypothesis that stylistic variation decreases in the course of the third year. Children’s lexical profiles were strikingly diversified at 1;8, whereas they appeared as variants of a same ‘grammatical profile’ at 2;6 and 3;3. We propose that the decline of stylistic variations reflects the impact of developmental constraints, such as the necessity for children to produce function words, which suggests that variations found in the youngest children are not determinant factors for subsequent lexical development.