Purpose: Dysprosody is considered a core feature of childhood apraxia of speech (CAS), especially impaired production of lexical stress. Few studies have tested the effects of intervention for dysprosody. This Phase II study with 3 children investigated the efficacy of a treatment targeting improved control of relative syllable durations in 3-syllable nonwords representing strong-weak (SW) and weak-strong (WS) stress patterns (e.g., BAtigu or baTIgu). Treatment sessions were structured along the principles of motor learning (PML) approach.
Method: Three children, age 7 to 10 years, with mild to moderate CAS and normal language development participated in an intensive 3-week treatment. Within-participant designs with multiple baselines across participants and behaviors were used to examine acquisition, generalization, and maintenance of skill.
Results: All children improved in their ability to control relative duration of syllables in SW and WS nonwords. Improvement was also noted in control of loudness and pitch contrasts. Treatment effects generalized to untreated nonword stimuli, but minimal change was seen in production of real words.
Conclusion: Findings support the efficacy of this approach for improving production of lexical stress contrasts. Structuring the intervention according to the PML approach likely stimulated strong maintenance and generalization effects.