Voice onset and articulatory constriction requirements in a speech segment and their relation to the amount of stuttering adaptation

This study evaluated the hypothesis that the amount of stuttering adaptation increases as the number of requirements for the prompt onset of phonation and complete articulatory constriction across passages decreases. To test this prediction, three special reading passages were constructed. The number of requirements for the quick initiation of phonation and complete articulatory constriction decreased from passages I to II to III. Eleven stutterers read each passage five times. Of these individuals, seven exhibited the well-known adaptation effect on all three selections. However, adaptation increased significantly from passage I to II to III. Among the remaining four subjects, three failed to adapt on passage I which contained the greatest number of requirements for the prompt onset of phonation and complete articulatory constrictions. These results were interpreted as supporting the hypothesis under test.