Recent developments in speech motor research into stuttering.

This paper discusses recent speech motor research into stuttering within the framework of a speech production model. There seems to be no support for the claim that stutterers differ from nonstutterers in assembling motor plans for speech. However, physiological data suggest that stutterers may at least have different ways of initiating and controlling speech movements. It is hypothesized that stuttering may be the result of a deficiency in speech motor skill. Furthermore, objections to the use of stuttering frequency as a severity index are formulated and future developments in the assessment of speech motor behavior in stuttering are described.