Control of children's stuttering with response-contingent time-out: behavioral, perceptual, and acoustic data.

Many stuttering treatments incorporate contingencies for stuttering that are thought to contribute to treatment effectiveness. One contingency used in a number of treatment programs for children is time-out (TO) from speaking. However, although TO has been shown to control stuttering in adults there are no clear demonstrations of this effect in children. One aim of the present study was to demonstrate in the laboratory that TO reduces stuttering in children. Three school-age children spoke in a single-subject ABA experiment. In the B phase, a red light was illuminated for 5 seconds when the subject stuttered, during which time the subject stopped talking. Two of the three children showed clear reductions in stuttering in response to TO. The second aim of the study was to detect whether the children who responded to To adopted an unusual speech pattern in order to control their stuttering. Listeners did not detect any differences between the perceptually stutter-free speech of baseline conditions and that of TO conditions, and a subsequent acoustic analysis revealed a reduction in the variability of vowel duration during TO in one subject and no changes in the other. The theoretical and clinical implications of the findings are discussed.