Sound production treatment for acquired apraxia of speech: Effects of blocked and random practice on multisyllabic word production.

Purpose: This study was designed to examine the effects of practice schedule, blocked vs random, on outcomes of a behavioural treatment for acquired apraxia of speech (AOS), Sound Production Treatment (SPT).

Method: SPT was administered to four speakers with chronic AOS and aphasia in the context of multiple baseline designs across behaviours and participants. Treatment was applied to multiple sound errors within three-to-five syllable words. All participants received both practice schedules: SPT-Random (SPT-R) and SPT-Blocked (SPT-B).

Result: Improvements in accuracy of word production for trained items were found for both treatment conditions for all participants. One participant demonstrated better maintenance effects associated with SPT-R. Response generalisation to untreated words varied across participants, but was generally modest and unstable. Stimulus generalisation to production of words in sentence completion was positive for three of the participants. Stimulus generalisation to production of phrases was positive for two of the participants.

Conclusion: Findings provide additional efficacy data regarding SPT's effects on articulation of treated items and extend knowledge of the treatment's effects when applied to multiple targets within multisyllabic words.