Laryngeal movement during deglutition was analyzed by means of cineradiography on fortyeight males of different age groups who had no pathology. The film was analysed using a film motion analyzer and the laryngeal movement was measured in two directions, horizontal and vertical.
As a result, the vertical movement associated with swallowing was divided into 5 phases: 1) the slowly ascending phase, 2) the rapidly ascending phase, 3) the pause at the position of maximum rise, 4) the rapidly descending phase, and 5) the slowly descending phase.
The slowly ascending phase was observed during the period of voluntary stage (the first stage) of deglutition, whereas the rapidly ascending phase was observed during the period of reflexive stage (the second stage). The average duration at the maximum position of rise was 0. 24 seconds. The descending phase appeared during the third stage of deglutition. Throughout these phases, the greatest time difference as related to aging, was noted in the slowly ascending phase. There were no notable time differences among the different age groups in the rapidly ascending phase and in the pause at the maximum position of rise. There were some differences among the different age groups in the extent of vertical laryngeal movement and in the time required for it. However, there were no notable differences in the extent of horizontal movement and in the time for the second stage among the different age groups.