Download Swallowing

PHASES OF SWALLOWING
1. Oral phase
a. function of the oral phase is to prepare foods for swallowing and to
deliver the swallow-ready food to the back of the mouth.
2. Pharyngeal phase
a. characterized by elevation of the larynx (which shortens the pharynx),
and closure of the velopharyngeal valve
b. requires the rapid coordination of multiple structures – needs intact
motor and sensation (CN IX, X)
c. Elevation of the base of tongue and sensory afferents from the tongue,
pharyngeal walls, and vallecula trigger the pharyngeal phase of
swallowing (CN IX, X)
d. soft palate is tensed, elevated and angled to seal the nasopharynx as the
bolus advance (contraction of the palatopharyngeus, tensor veli
palatine, and levator veli palatine.)
e. muscles of the base of tongue and lateral tonsillar pillars also contract,
which keeps the bolus from spilling back into the oral cavity. As the
base of tongue pushes posteriorly, the pharyngeal walls contract and
the larynx is elevated
f. The pharyngeal phase lasts less than one second.
3. Esophageal phase
a. Peristalsis moves the bolus down the oesophagus