Is covert articulation impaired in developmental stuttering?

Adults who stutter (AWS) have been reported to show difficulties in nonword repetition tasks, where covert articulation supports the maintenance of phonological information during the retention interval. However, it remains unclear whether these difficulties reflect impaired covert articulation, auditory-phonological encoding, overt articulation, or aspects of executive function/attention. It is also unknown whether such difficulties characterize any, some, most, or all AWS. To address these questions, we administered spoken and written versions of a phonological memory task-both using printed nonwords during encoding-alongside a visuospatial memory task, to twenty AWS and forty matched controls, and conducted both group-level and individual-level analyses. As a group, AWS underperformed controls on all three tasks, but their difficulties were more pronounced on the two phonological tasks, suggesting impaired covert articulation. However, substantial heterogeneity emerged at the individual level, highlighting the importance of individual-level analyses and conclusions.