Factors contributing to the reduction of stuttering during singing.

This study was conducted to determine if the reduction of stuttering typically observed during singing is associated with altered vocalization or the familiarity of the melody and lyrics of the song sung by the stutterer, or both. Subjects were eight adult male stutterers. Prior to testing, each of these individuals demonstrated that he knew the melody and lyrics of a well-known song from memory. Subsequently, subjects were asked to read these lyrics aloud and then sing them. Next, subjects had to read aloud and then sing a set of unfamiliar lyrics to the conventional melody of the same song. The stutterers' reading and singing performances were audiotaped. The dependent measures of utterance duration and stuttering frequency were extracted from the tapes. Results showed that subjects' utterance durations were significantly longer during singing than reading. The main effects of singing and familiarity were both associated with significant reductions in stuttering frequency. The greatest decrement in stuttering occurred in the condition where subjects sang the familiar melody and lyrics. These findings were interpreted to mean that changes in vocalization cannot account for all of the decrease in stuttering that occurs during singing. During song, the familiarity of the melody and lyrics being produced may also affect stuttering frequency.