Self- versus investigator-administered presumed fluency reinforcing stimuli.

The effects of self-administered and investigator-administered presumed fluency reinforcing monetary rewards for perceived fluency increases on the disfluency frequency rate of 17 adult stutterers were studied. Subjects read aloud during 11 one-minute segments under three conditions: one in which no reinforcer was administered at the end of each one-minute segment, a self-administered reinforcement condition, and an investigator-administered reinforcement condition. Although less stuttering was found in the two experimental conditions (with significantly less stuttering occurring in the self-administered fluency reinforcing condition than in the control condition), an increase in stuttering was observed in those reading segments which followed the administration of presumed fluency reinforcing stimuli. These results were interpreted to suggest that although the concept of self-reinforcement may be clinically useful, the operant learning paradigm may be insufficient in providing an adequate description of the events taking place following the administration of fluency contingent reinforcing or punishing stimuli.