Speech sequence skill learning in adults who stutter

The present study compared the ability of 12 people who stutter (PWS) and 12 people who do not stutter (PNS) to consolidate a novel sequential speech task. Participants practiced 100 repetitions of a single, monosyllabic, nonsense word sequence during an initial practice session and returned 24-h later to perform an additional 50 repetitions. Results showed significantly slower sequence durations in the PWS compared to PNS following extensive practice and consolidation. However, the hypothesis that poor performance gains in PWS compared to PNS during practice would be maintained following a 24-h consolidation period was not supported. Further descriptive analysis revealed large within group differences in PWS which to some extent were attributed to a subgroup of PWS who failed to show any improvements in performance following practice or consolidation. The results and the possible presence of subgroups of PWS are discussed with regard to their limitations in motor learning abilities.Educational objectives: The reader will be able to (1) explain the difference between practice and learning, (2) define consolidation and explain the importance of measuring performance following a consolidation period, (3) understand past research on PWS’ performance during both speech and nonspeech motor tasks, and (4) explain why individual differences in practice effects and learning may have important implications for client variability in treatment outcome.

► There was no significant difference in accuracy between PWS and PNS on day one or day two of practice. Similarly, there was no significant main effect for Practice, or a Group × Block interaction on day one or day two.
► PWS demonstrated significantly slower sequence durations compared to PNS across practice trials on day one and following a consolidation period on day two. No significant Group × Block interaction was found for day one or day two.
► Descriptive analysis of individual differences in sequence duration revealed higher variability in the PWS than PNS. More specifically, four out of the 12 PWS demonstrated very little improvement in performance on day one of practice and following a consolidation period.
► Tests of retention showed the ability of both PWS and PNS to retain their improvements in performance from day one of practice following a 24-h consolidation period on day two for the variables accuracy, response time, and sequence duration.