Skip to main content
. Author manuscript; available in PMC: 2014 Dec 1.
Published in final edited form as: Respir Physiol Neurobiol. 2013 Aug 30;189(3):10.1016/j.resp.2013.08.009. doi: 10.1016/j.resp.2013.08.009

Figure 5.

Figure 5

Dual valve system hypothesis. The side by side circles represent the two valves, the larynx and the upper esophageal sphincter. Closure of the two valves is controlled by the thyroarytenoid and the cricopharyngeus muscles, respectively. The valve aperture is represented on a scale from white (maximum opening) to black (maximum closure). Note: during the expiratory phase of eupnea there is some thyroarytenoid activity. ** Thyroarytenoid and cricopharyngeal electromyogram waveform averages across multiple behavior occurrences during cough and swallow. The vertical gray line in the second and third panels is the midline marker of the behavior execution, and during cough this represents the transition from inspiration to active expiration.