Cross, D., and Olson, P. Articulatory-laryngeal interaction in stutterers and normal speakers: effects of a bite-block on rapid voice initiation. Journal of Fluency Disorders, 1987, 12(6), 407-418.

The purpose of this study was to investigate the effects of restricting jaw movement with a bite-block on the voice reaction times (VRT) of adult stutterers and normal speakers. Ten stutterers and ten normal speakers initiated the sound /(/ as rapidly as possible in response to 1 Khz cues in a nonbite-block and bite-block condition. In the nonbite-block condition all responses were initiated from a mandibular "closed" position. In the bite-block condition the jaw was fixed in a position approximating average jaw displacement for production of /(/ in a VRT task. Results showed the group mean VRTs for the stutterers were significantly longer than for the normal speakers in both experimental conditions. Group mean VRTs were also significantly faster in the bite-block than the nonbite-block condition for both groups. Investigation of individual subject data, however, revealed that unlike the normal speakers, a subgroup of stutterers exhibited atypically long reaction times and an increase in VRTs with the jaw fixed. The possible role of neurophysiological interactions between articulatory and laryngeal behavior in stuttering is discussed.