Abstract:

A comprehensive account of speech production should explain interspeaker variation. Toward this end, a study was performed with eight speakers to investigate whether individual kinematic performance limits, as reflected in a speechlike cyclical task, could account for differences in speech kinematics. Kinematic data from cyclical CV movements at rates from 1--6 Hz of the lower lip, tongue blade, and tongue dorsum were compared with data from speech utterances in different conditions, including normal, fast, clear, and slow. There were differences in movement distance, peak velocity, and duration among the speaking conditions and among the speakers. Three speakers produced ``clear'' speech utterances with distances, peak velocities, and durations that were greater than normal. The data from two of the three may reflect some increased effort for clear speech. The amount of overlap of the speech data and cyclical data varied across speakers, ranging from little overlap to complete overlap. Thus, in general, the cyclical task did not define a kinematic performance space within which speech movements were confined. These results will be discussed in relation to differences between the tasks, possible interactions between production and perception, and possible differences in motor and/or perceptual performance capacities. [Work supported by NIDCD.]