Suppression of normal speech disfluencies through response cost.

The speech disfluencies of five normal-speaking college students were modified in a series of 10 to 17 sessions by means of response cost. During Point-loss, each disfluency (repetition or interjection of a sound, syllable, word, etc.) resulted in the loss of a penny, as indicated on a screen in front of the subject. Disfluencies were suppressed and kept at very low levels for four of the subjects during the punishment procedures, and there was general resistance to extinction. Even though points were subtracted only during speech, there was a tendency for disfluencies to decrease, though not as markedly, during reading probes as well.