Abstract
We conducted experiments to determine the changes in swallowing attributable to differences in the property of the materials to be swallowed. The maximum swallowing capacity for water and 2% Throughsoft STM (an aqueous solution containing a starch power) was always larger by about by 20 ml for water than for 2% Throughsoft STM, though the absolute amount swallowed varied with each individual. On the other hand, the concept of ease in swallowing, presumably involving a light load was advanced in this study. Bolus volume of each swallow during continuous swallowing was close to that of easy swallowing. The volume did not apparently differ from that of water nor that of 2% Throughsoft STM. These results seem to suggest that the root of the tongue judges the property of the material to be swallowed before the completion of the stage II of swallowing, at latest, and actively determines the appropriate amount of material to be swallowed.
