Prelinguistic Pragmatic Functions as Predictors of Later Expressive Vocabulary

Abstract

This study tested the relationship between prelinguistic pragmatic functions and later expressive vocabulary of children with mild to moderate developmental delays. Fifty eight toddlers with Bayley Mental Development Indices from 35-85 participated. All children had fewer than 3 words in their expressive vocabularies and showed at least one instance of intentional prelinguistic communication prior to testing. At the beginning of the study, children's prelinguistic behavior regulation, social interaction, and joint attention were measured. One year later, children's expressive vocabulary was measured. Results indicated that rate of joint attention and rate of communication were statistically significant predictors of later expressive vocabulary. Rate of behavior regulation was not a predictor. There were too few instances of social interaction to test its predictive validity.