Figure 19 - Role of UES closure muscles in esophago-UES relaxation reflex.

Rapid injection of air into the esophagus of a decerebrate cat caused the CP to relax concomitant with activation of UES opening muscles, i.e., GH and TH. ESO#, esophagus number of centimeters from LES; GH, geniohyoideus; TH, thyrohyoideus; CP, cricopharyngeus; IA, intraarytenoideus; CT, cricothyroideus. (Source: Lang et al.,¹¹² with permission of the American Physiological Society.)