Fig. 9. Kinematics of the dorso-ventral length of the I3 muscle during swallowing. (A-D) Data from each of the four individual swallowing sequences plotted as length (mm) as a function of time (ms). The left panels show the dorso-ventral length of the I3 muscle at the lateral groove. The right panels show the dorso-ventral length of the I3 muscle at the line of the jaws. (E) Normalized, averaged and smoothed dorso-ventral lengths of I3 during the swallowing cycle. Data are shown as mean ± 1 S.D. (F) Schematic diagrams indicating the dorso-ventral length of I3 at the lateral groove for frames 1, 9, 18 and 22, highlighted with a black line. The dorso-ventral lengths of I3 at the jaws for frames 1, 9, 18 and 22 are shown on the right, highlighted with a black line. Compare original frames in Fig. 5. For definitions of periods t1, t2 and t4, see Materials and methods.