Phonological and orthographic reading routes in French-speaking children with severe developmental language disorder

This study aims to assess written word recognition in French-speaking children with severe developmental language disorder (DLD), using a task of reading in silence. The objective is to determine if the balance between the phonological reading route and the orthographic route of these children is similar to that of typically developing children, on the basis of the so-called "dual route" model.

A visual lexical decision task was used in 19 children with severe DLD (average age: 11.01 years), 19 control children of the same reading level (RC children, average age: 8.12 years), and 19 children of the same chronological age (AC children, average age: 10.84 years). This task included words and pseudowords associated with these words: pseudohomophones, pseudowords phonologically close but visually distant to the true words, visually close but phonologically distant pseudowords.

The groups did not process the pseudowords in the same way. Children with severe DLD were more successful than RC children for pseudohomophones. They tended to be less successful for phonologically close and visually distant pseudowords. They were similarly successful for visually close and phonologically distant pseudowords. Children with severe DLD were less successful than AC children with each type of pseudowords.

These results suggest that children with severe DLD do not simply present a homogeneous delay in their ability to recognize written words but rather a deviant development compared to RC children, with a stronger reliance on the orthographic reading route compared to the phonological one. It is likely that the phonological difficulties of children with severe DLD have hindered the development of their phonological reading route which, in turn, have hindered the development of their orthographic route.