Phonological Representation across Subtypes of Children with Speech Sound Disorders

Objectives: This study aimed to investigate the relationship between speech sound errors and phonological representations by comparing the performance of typically developing (TD) children and children with speech sound disorders (SSD), and among the subtypes of SSD. Methods: The study involved 52 children, including 26 children with SSD and 26 TD children. Two experimental tasks were administered to examine group differences in performance: a phonological representation judgment task and a nonword repetition task. The phonological representation task consisted of varying consonant/vowel manipulations and feature contrasts. The nonword repetition task was used to compare phonological accuracy and word accuracy. Children with SSD were further classified into articulation disorder, phonological delay, and phonological disorder subgroups based on surface speech error patterns. Results: Children with SSD performed significantly lower than TD children on the phonological representation judgment task. Performance was higher in the vowel and multiple-feature conditions. Subgroup comparisons revealed that children with articulation disorders outperformed those with phonological delays and phonological disorders. In the nonword repetition task, children with SSD showed lower phonological accuracy and word accuracy than TD children, with the phonological disorder group demonstrating significantly lower phonological accuracy than both the articulation and phonological delay groups. Conclusion: The study confirms that children with SSD exhibit lower performance in phonological representation tasks compared to TD peers. It further suggests that articulation disorders are associated with relatively stronger phonological skills than either phonological delays or phonological disorders. These findings highlight that speech sound errors are closely linked to deficits in phonological representations and support the need for targeted interventions by subtype.