Patterns of tongue movement

This paper discusses the pivot pattern of tongue movement. In this pattern, there is a point in the vocal tract where there is no motion, but there is motion at points of the vocal tract anterior and posterior to the pivot point. Based on tongue edge tracings of frames from ultrasound and x-ray dynamic imaging of the vocal tract, I will show that the pivot pattern is used in a variety of sequences, and I will discuss the possible causes of the pattern.