Fig. 9.

Simulated local strain rate during swallowing. Local strain rate is computed to serve as a comparison with prior experimental work deriving aligned strain rate from lingual pressure-gated phase-contrast MRI and DTI tractography (4, 5). In the current simulation, local strain rate is calculated as a difference between consecutive images of the local stretches divided by time intervals between times when these images were obtained. The images of local stretches were collected at 1-ms intervals, and then the strain rates were collected at specified times denoted in the left corners of the presented images. The color code represents the magnitude of the strain rate in direction of muscle fibers ξ. Strain rate is displayed as regions of contraction rates (red) or elongation rates (gray).