Effects of two types of motor practice on stuttering adaptation.

The present study identifies and compares the effects of two types of motor practice on stuttering adaptation. The study was designed to determine if whispered reading practice affects stuttering adaptation, and if practice in reading aloud is superior to whispered reading in promoting adaptation. In a control condition, eight stutterers read one of two matched passages aloud five times in succession. In an experimental condition, the remaining passage was read aloud on the first and fifth trials, and was read in a whisper on Trials 2, 3, and 4. The results indicated that (1) the stutterers' adaptation in the control condition was similar to the typical course of adaptation, (2) the three intervening whispered readings in the experimental condition neither inhibited nor facilitated adaptation, and (3) practice in reading aloud was superior to whispered practice in promoting stuttering adaptation. It was concluded that whispered reading practice does not facilitate stuttering adaptation when the measurement of that process requires reading aloud. Traditionally, adaptation has been measured only during reading done aloud. Consequently, practice in reading aloud has the greatest positive influence on the adaptation process.