Speech shadowing characteristics of stutterers under diotic and dichotic conditions.

The purpose of this study was to compare adult stutterers' and adult nonstutterers' fluent speech patterns produced during one nonshadowed reading and two speech shadowing conditions. Subjects' speech error rates, shadowing strategies, and fluent speech segment durations were obtained during baseline, diotic speech shadowing, and dichotic speech shadowing conditions. Results indicated that stutterers produced fewer speech production errors (i.e., omissions, substitutions, and insertions) than nonstutterers during each shadowing condition. Stutterers also favored the use of a word-by-word speech shadowing strategy, while nonstutterers utilized both word-by-word and small phrase shadowing strategies. Finally, stutterers exhibited significantly longer vowel and phrase durations than nonstutterers during the shadowing conditions.