Correlation of nonword repetition accuracy with vocabulary size and other measures of linguistic development in children with phonological disorders

A growing body of research has documented effects of phonotactic probability on young children’s phonological processing. This study extends this research in two ways. It compares nonword repetitions by 40 young children with phonological disorders with those by 40 age peers with typical phonological development and it also examines the relationship between the frequency effect in the nonword repetition task and other measures of phonological ability across a larger group of children. All children repeated low-frequency sequences less accurately than high-frequency sequences. The children with phonological disorders were less accurate overall, but showed no larger disadvantage for the low-frequency sequences. Across the larger group, the size of the frequency effect was correlated with vocabulary size, but it was independent of measures of speech perception and articulatory ability. These results support a view of phonological acquisition as the gradual development of multiple types of phonological representation, with robust higher-order symbolic categories (phonemes) emerging only later, as generalizations about sublexical sound patterns in the enlarging lexicon. Within this framework, phonological disorders seem to involve deficits at a more basic level of phonological