The Effects of Repeated Practice and Rate/Rhythm Control Treatments on Sound Production Accuracy (Wambaugh et al., 2012)

Purpose This investigation was designed to elucidate the effects of repeated practice treatment on sound production accuracy in individuals with apraxia of speech (AOS) and aphasia. A secondary purpose was to determine if the addition of rate/rhythm control to treatment provided further benefits beyond those achieved with repeated practice. Method A single-subject design was employed with 10 speakers with chronic AOS and aphasia. Articulation accuracy served as the dependent measure. Participants received repeated practice treatment until a plateau in performance was observed or high levels of accuracy were achieved. If performance criterion was not reached, rate/rhythm control was added to the treatment to determine if additional gains would be made. Results For 8 of the participants, improvements were evident for all applications of repeated practice treatment, and positive response generalization was observed in most cases. When rate/rhythm control treatment was applied, modest additional gains were apparent for the majority of the applications. The 2 participants who did not benefit from repeated practice treatment also did not show improvements with rate/rhythm control treatment. Conclusions Repeated practice treatment resulted in improved articulation for the majority of participants. The amount of improvement varied within and across participants. Rate/rhythm control appeared to have limited additional benefits for some participants.