Figure 8 - a: Esophagoglottal closure reflex.

One frame of videoendoscopic view of human (i), cat (ii), monkey (iii), and opossum (iv) glottis. 1, posterior epiglottis; 2, vocal cord (fold); 3, arytenoid; u, area of upper esophageal sphincter (UES) opening. B: Esophagoglottal closure reflex. Still frames from videoendoscopic recordings of glottal closure response to intraesophageal air injection in a cat. Glottis immediately before a 40-mL intraesophageal air injection (A) and 0.3 (B), 0.4 (C), 0.8 (D), and 1.0 (E) seconds after 40-mL esophageal air injection. u, Area of UES opening. Note that time intervals between frames are not equal. (Source: Shaker et al.⁶¹ with permission from the American Physiological Association)