AUTHOR=Nishino Takashi TITLE=The swallowing reflex and its significance as an airway defensive reflex JOURNAL=Frontiers in Physiology VOLUME=3 YEAR=2013 URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2012.00489 DOI=10.3389/fphys.2012.00489 ISSN=1664-042X ABSTRACT=

Swallowing function, in humans, is very complex. Swallowing plays, not only an important role in food digestion, but also a major role in preventing the entrance of food and/or other materials into the lower respiratory tract. To achieve this, precise coordination is necessary between breathing and swallowing since the pharynx serves as a common pathway for both respiration and digestion. The swallowing reflex consists of afferent pathways, central integration, and efferent pathways. Any defect or disorder along reflex arc can cause a potential delay or impairment in swallow function. The swallowing reflex can be modulated not only by pathological factors but also by physiological factors. Among these, timing of swallows in relation to the phase of respiration may be the most important factor that determines the occurrence of pulmonary aspiration, since phases of inspiration and the expiration-inspiration transition are the most vulnerable for pulmonary aspiration.