Complex working memory in adults with and without stuttering disorders: Performance patterns and predictive...

Available studies of working memory (WM) in speakers who stutter tend to rely on parent report, focus on phonological WM, or measure WM in combination with other processes. The present research aimed to: (1) compare complex WM in adults who stutter (AWS) and adults who do not stutter (AWNS); (2) characterize group performance patterns; and (2) determine whether WM predicts stuttering severity.

Eighteen AWS and 20 AWNS completed parallel verbal and spatial span tasks in which to-be-remembered items were interleaved with a distracting task across varying set sizes. Dependent variables included the number of correctly recalled items, accuracy on distraction tasks, and detailed analyses of item-level responses. We further examined whether span scores predicted subjective and objective measures of stuttering severity.

Relative to AWNS, AWS showed poorer recall, specifically on short set sizes in the spatial task. Groups performed similarly on distraction tasks and showed comparable error patterns. Predictive relationships differed by span task and severity measure. Lower verbal span scores predicted greater stuttering impact and more overt stuttering behaviors; lower spatial span scores predicted lower impact and was unrelated to overt behaviors.

Findings suggest that AWS differ subtly from AWNS in WM performance. Group differences became more apparent under certain task conditions but could not be attributed to specific underlying processes. Data further indicated a complex relationship between WM and stuttering severity. Overall, results corroborate previous studies linking stuttering to domain-general weaknesses, but highlight the need for additional research to clarify the nature of this relationship.