Anthony J. Caruso

A Speech Motor Control Perspective on Stuttering: Preliminary Observations

Most physiological investigations of stutterers’ speech productions have focused on descriptive measures of muscular events and structural movements, air pressures and flows, and the resulting acoustic waveform during instances of stuttering. Specifically, during moments of stuttering, stutterers have difficulty producing: (1) proper onsets, offsets, transitions, and durations of muscle (in)activation prior to or during stuttering (Sheehan & Voas, 1954; Ford & Luper, 1975; Metz, Conture & Colton, 1976; Freeman & Ushijima, 1978; Shapiro, 1980; Stromsta & Fibiger, 1980), (2) appropriate degrees of muscle excitation (Sheehan & Voas, 1954; Ford & Luper, 1975; Freeman & Ushijima, 1978; Shapiro, 1980; Stromsta & Fibiger, 1980; McClean, Goldsmith & Cerf, 1984), and (3) appropriate timing of lip, jaw and tongue movements (Hutchinson & Watkin, 1976; Zimmermann, 1980b, 1980c).