Treating Childhood Apraxia of Speech

Childhood apraxia of speech is a developmental speech sound disorder that may lead to persisting speech errors, often despite years of treatment. Such impairments may lead to social, academic, and vocational limitations. Thus, there is a need to explore alternate treatment approaches. This study will explore how to improve speech sound production in school-age children with CAS by modifying a standard speech therapy program. Two adaptations to speech therapy will be tested in a 2 x 2 randomized group design.

In Aim 1, a standard treatment schedule of 2 one-hour sessions per week will be compared against a treatment sequence beginning with an intensive therapy schedule (10 hrs of treatment in one week), which will then transition to a more distributed practice schedule. This treatment modification is intended to minimize erred practice between training sessions in the early stages of learning, then foster generalization through increased time between practice sessions.

In Aim 2, a standard treatment that includes only verbal feedback to the client during speech practice will be compared against a treatment sequence that initially includes real-time ultrasound visual feedback of the tongue during speech, which will be faded over the course of treatment. Ultrasound visual feedback is designed to train articulatory movements. It may enhance children's understanding of the articulatory goals of speech movement patterns by comparing executed tongue movements with intended movements. Prior case reports and single subject experimental designs have shown that speech sound production may be enhanced by including ultrasound visual feedback, although no prior randomized group studies have been conducted.

Beside these modifications, the other aspects of treatment will be held constant. Outcomes will be evaluated by tracking changes in percent consonants correct from a large speech sample, scored by individuals who are blind to treatment status. The four groups will be compared to determine the extent to which speech sound therapy can be enhanced through a treatment sequence that begins with intensive practice and/or with ultrasound visual feedback.

Inclusion criteria

• Native English speakers who hear English as the dominant language in their home setting.
• Must pass a hearing screening.
• Score at or better than -2 standard deviations from the mean on the Matrix Reasoning Task of the Wechsler Abbreviated Scale of Intelligence - 2nd Edition (WASI-2; t-score ≥ 30), Peabody Picture Vocabulary Test - 4th Edition (PPVT-4; standard score ≥ 70), and the Following Directions subtest of the Clinical Evaluation of Language Fundamentals - 5th Edition (CELF-5; scaled score ≥ 3).
• Goldman-Fristoe Test of Articulation - 3rd Edition (GFTA-3) percentile ≤ 5th).
• A diagnosis of CAS will be verified based on a polysyllable picture naming task, diadochokinetic task (puh-tuh-kuh), and syllable repetition task.

Exclusion criteria

• Parent report or direct evaluation reveals oral-facial structural abnormalities (e.g., cleft palate).
• Parental report of neurobehavioral disorders (e.g., autism spectrum disorders, ADHD, obsessive-compulsive disorder), or vision problems that are corrected with glasses/contacts.
• Fail a hearing screening, or failure to meet criteria listed above as Inclusionary