부산대학교 도서관

The purpose of this study was to investigate the effects of mechanical properties of foods on tongue movement at initiation of swallowing. Five healthy adult volunteers freely ate four types of food (3ml of hard gel, soft gel, sol and liquid). A probe was placed under the chin and the coronal section of the tongue was observed. Displacement of the dorsal surface of the tongue from the under surface of the chin was recorded against time using M-mode ultrasound imaging. We analyzed up-down movement of the tongue with the grooving depth, and the velocities of descending and ascending of grooving. The results obtained were as follows. 1) The grooving depth differed significantly among the foods; the sol showed the maximum and water exhibited the minimum. 2) Mechanical properties significantly affected the velocity of descending grooving, which was greatest for the sol. 3) The velocity of descending grooving was greater than that of ascending grooving for all the food samples. The results suggested that tongue movement at the initiation of swallowing changes according to the mechanical properties of foods.