Reinforcing fluency in stutterers: An experimental study

Subject-specific periods of fluent reading responses of three adult stutterers were positively reinforced with the presentation of a dime. Subjects were run individually through a sequence of two base rate, two experimental, and two extinction sessions, each session lasting 45 min. Periods of fluent reading responses increased during the experimental condition for each of the three subjects. When the reinforcer was withdrawn during the extinction condition, the frequency of fluent periods showed a decrease. Concomitantly, disfluencies decreased during the experimental condition and they increased during the extinction condition. The clinical implications of fluency manipulation as against disfluency manipulation are discussed.