Fluency and disfluency; Illusion and identification

At approximately the same time, two lines of research have studied disfluencies from different orientations—one in stuttering and the other in normal speech. In certain important respects the findings of these separate lines differ. Resolution of these differences, which is particularly important for understanding stuttering in its relation to disfluency and fluency, has been precluded because the two research areas have remained essentially isolated from each other.Progress in understanding stuttering would benefit considerably from adequate attention to the findings of research on disfluency in normal speech, which already has yielded a substantial amount of information pertinent to the concepts of fluency and disfluency; the nature and extent of disfluency; the linguistic and cognitive significance of disfluencies; and the differentiation between normal and abnormal disfluency.