Selective movement of the lateral aspects of the pharyngeal walls during velopharyngeal closure for speech, blowing, and whistling in normals.

The frontal and lateral cinefluorographic views of five normal subjects performing speech, blowing, and whistling tasks were synchronized in order to observe where the greatest degree of medial movement in the lateral aspects of the pharyngeal walls was occurring in relation to structures observed in lateral view. The results of the synchronization procedure indicates that for all five subjects, maximum medial excursion in the lateral walls of the pharynx occurred at the level of the full length of the velum and hard palate, well below the levator eminance. It is hypothesized that this observed interaction may be due to the select contraction of those fibers of the superior constrictor muscle which enter the velum via the lateral walls and those fibers attached to the pterygoid plates as well as levator muscle activity. It is also suggested that definitive physiological data must be obtained from further study of combined EMG and fluoroscopic procedures.