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Velopharyngeal Function
2/17/00
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Soft Palate
• Posterior extension of soft palate
• Composed of muscular fibers
• Movement changes volume & shape of the nasal &
oral cavities
• Speech: nasal-nonasal phonetic distinction
– “Closed”- Soft palate elevated and seals against
posterior pharyngeal wall
– “Meaning”- Soft palate is lowered (acoustic energy
passes through nasal cavity)
• Swallow: Soft palate closes when bolus passes
from oral cavity to pharynx
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Muscles: Soft Palate
• Levator veli palatini
• Tensor veli palatini
• Uvula
• Palatoglossus
• Palatopharyngeus
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Levator Palatini
Temporal
Bone
• Elevates the soft palate
• Pull soft palate toward
post. pharyngeal wall
• Dilates eustachian tube
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Tensor Veli Palatini
Eustachian
Tube
• Dilation of eustachian tube
• Tenses the palate assisting in
velopharyngeal closure
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Uvula
• Medial & posterior portions of the soft palate
• Arises from posterior nasal spine of palatine bone
& palatal aponeurosis
• Fibers run the length of the soft palate
• Inserts into mucous membrane of the velum
• Contraction shortens the velum, bunching it up
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Palatoglossus
• Anterior facial pillars
•Depresses sides of soft palate
•Pulls sides of tongue up and back
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Palatopharyngeus
Soft Palate
• Posterior facial pillar
• Depress soft palate
• Elevate pharynx or larynx
Palatine
Tonsil
Palatoglossus
Posterior
Faucial
Arch
Palatopharyngeus
Anterior
Faucial
Arch
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Patterns: Velopharyngeal Closure
• Basic action the same in speech & swallowing
– Close the entry into the nasal cavity or open it
• Sex differences:
– Males velum forms acute angle in the orientation to the
PPW
– Females have a right angle orientation
– Extent of the area of the velopharyngeal seal is greater
in females
– Midpoint of closure in the nasopharynx
• Superior to palate in males
• Inferior to palate in females
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Patterns of
Velopharyngeal
Action
Velum
A.
Velopharyngeal
Port
A. Coronal (A-P movement of velum)
B.
B. Sagittal (Lateral pharyngeal wall
Lateral
movement)
Pharyngeal
Wall
C.
C. Circular (Equal movement of lateral
pharyngeal wall and velum)
D. Circular with Passavant’s Ridge
(Lateral pharyngeal wall, velum &
posterior pharyngeal wall)
D.
Passavant’s
Ridge
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Velopharyngeal Function & Age
• 3- 5 years: velar-adenoidal valving
– exploits large adenoidal mass in young children
• Nasal airway narrow
• Adenoid atrophy
changes pattern
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Velopharyngeal Actions
• Velum Elevation:
– Levator Palatini
– Velar positioning:
• Levator veli
palatini
• Palatoglossus
• Palatopharyngeus
•Velum Lowering:
–Muscle contraction
•Palatoglossus
•Palatopharyngeus
–Gravity
–Tissue Elasticity
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Swallowing
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Deglutition
• Main purpose: Transportation of bolus (mass of
masticated food ready to be swallowed) from oral
cavity to the stomach
• Sequence of Muscular Action:
– Trap bolus in the anterior region of oral cavity
– Move the bolus from the mouth to entrance of pharynx
– Admit the bolus into the esophagus, while entrance into
larynx is closed
– Transport bolus to esophagus to stomach
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Swallow: Structures Involved
• Lips (Anterior Seal)
• Tongue (Anterior Seal)
• Soft Palate (Closes velopharynx-Midpalatal)
(Opens-Esophageal)
• Pharynx (Opens for bolus)
• Larynx (Vocal folds close)
• Esophagus (Superior sphincter opens-Peristaltic
transport)
• Interruption of respiration: Apneic Interval
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Stage Descriptions
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Containment Stage
• Anterior seal formed by the lips & tongue tip or
blade
• Bolus held in a depression at the front of the
tongue
• Dorsum of tongue arches upward to assist bolus
containment
• Tongue performs a pooling action to contain the
bolus
• Posterior seal by the soft palate (descending to
make contact with the tongue
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Midpalatal Stage
• Bolus squeezed aborally (away from mouth)
by progressive wavelike elevation of the
tongue (anterior)
• Dorsum of tongue lowered to receive bolus
• Soft palate elevated in advance of the bolus
to open the oropharyngeal channel & close
the VP port
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Pharyngeal Compression Stage
• Begins: Bolus reaches faucial pillars & soft
palate
• Onset of reflexive control of deglutition
– Cessation of respiratory activity (apnea)
• Tongue flexes backward on hyoid bone to thrust
bolus posteriorly into the pharynx
– Vigorous tongue motion necessary
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Pharyngeal Engulfing Stage
• Larynx moves superior-anterior to tuck under the root of the tongue
• Epiglottis tips downward & backward to protect the opening into
the larynx
• False & true vocal folds adduct to form a laryngeal constriction
– prevents solid & liquid from entering the larynx
• Elevation of pharyngeal tube to “engulf” bolus
– Peristaltic wave: Involuntary contraction
• Superior esophageal sphincter opens receiving bolus
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Esophageal Stage
• Bolus moved by esophageal peristaltic contraction
to the gastroesophageal sphincter (entrance to
stomach)
• Respiration begins, soft palate descends to rest
position
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Stages of Swallow
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Bolus Transport Time
• Oropharyngeal Time= 2 seconds (young
adults); 3-4 seconds (older adults)
• Esophageal Time= 0.5-1 second
– liquids have faster times
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References
• Arvedson, J.C., & Rogers, B.T. (1993). Pediatric
swallowing and feeding disorders. Journal of
Medical Speech Language Pathology, 1, 203-221.
• Kennedy, J.G., III, & Kent, R.D. (1985). Anatomy
and physiology of deglutition and related
functions. Seminars in Speech and Language, 6,
257-273.
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