title: Sequence initiation performance by stutterers under conditions of response competition.
abstract: Male stutterers and nonstutterers were compared on their performance of a task that required tapping keys as rapidly and accurately as possible to reproduce different sequences of finger movements as soon as they had been demonstrated on a visual display panel. Testing using the right hand alone confirmed previous findings that stutterers are significantly slower than nonstutterers in initiating new movement sequences and make significantly more errors on initial sequences. Subjects were also tested on this sequence reproduction task while they performed concurrently a manual task with the left hand that required turning a knob in response to signal tones. The hypothesis underlying the study was that associated with stuttering is a dysfunction in the mechanisms regulating interhemispheric communication, and it was predicted that the concurrent task would interfere more with the sequence reproduction task performance of stutterers than with that of nonstutterers. A joint analysis of the speed and accuracy aspects of performance of the two tasks confirmed the prediction. Additional research required to clarify whether the effects are in fact due to the hypothesized interhemispheric mechanisms or to a generally greater susceptibility of stutterers to interference from any concurrent motor or cognitive activity is discussed.
authors.affiliation: Department of Psychology, Carleton University, Ottawa, Ontario, Canada.
authors.forename: W G
authors.initials: WG
authors.lastname: Webster
mesh_terms: D000328:Adult; D001288:Attention; D004292:Dominance, Cerebral; D006801:Humans; D011597:Psychomotor Performance; D011930:Reaction Time; D012691:Serial Learning; D013342:Stuttering / Q000523:psychology*