Early lexical and combinatorial development

Abstract

This study investigates the transitions from single word utterances to multiword combinations and documents the temporal connection between lexical and combinatorial spurts. This transition in early language acquisition occurs in the second year of a child's life, marking a significant developmental milestone. Three children were followed longitudinally from the time they began to produce single words until about one month after a combinatorial spurt was achieved. Kate was followed from the age of 1;5(9) to 2;1(14), Julianna from 0;11(28) to 1;9(22), and Emily from 1;1(28) to 1;11(25). Single words and word combinations were written down manually and audio-recorded. Analysis was based on the number of new words, word types, word tokens, new word combinations, word combination types and word combination tokens. Increases in MLU were also investigated.;The increase in the number of words and word combinations was plotted as a function of the week of the study. The cumulative graphs illustrate how the rate of single word growth begins gradually and peaks with a rapid surge of word growth, referred to as a lexical spurt. The time at which the spurt occurred can be viewed by looking at the upward change in slope of the cumulative curves. Word combinations began to appear during the weeks in which the lexical spurt occurred. Thus, the lexical spurt coincided with the emergence of syntax. Shortly after the children's emergence of syntactic activity, word combinations were produced at an increased rate and consequently peaked producing a combinatorial spurt.;New words were classified into grammatical categories and new word combinations were grouped based on early meanings of sentences. Nouns accounted for the majority of the words acquired by the subjects. Verbs began to enter the children's vocabulary at a greater rate with the emergence of syntax. Along with the combinatorial spurt, word combinations classified as action utterances became substantial in number and increased in comparison to children's earliest and most primitive word combinations which were categorized as demonstrative naming utterances, those containing a pointing word and a label, e.g., the dog.;Our results suggest that early lexical and combinatorial development are part of a lexicogrammar. The lexical spurt and the emergence of syntax are part of one process. With the continued growth in vocabulary and the construction of early sentences, children's language structure advances and mirrors adult language.