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Supralaryngeal Anatomy
Vocal Tract
• Articulation: a joining of structures loosely
to allow movement
– For speech: modification of the airstream into
the various sound of speech
– Airstream is either set into vibration at the
larynx (voiced sound) or flows through open
glottis unimpeded (voiceless)
– Modification occurs in vocal tract
• Throat, mouth, nose
Vocal Tract
• Sounds are formed in three ways:
–Exploding the airstream with
bursts of pressure
–Constricting it to generate
turbulence
–Resonating it to shape different
qualities of tone
Articulators
• Articulators or vocal tract include:
–Tongue
–Lips
–Jaw
–Velopharynx
–Pharyngeal cavities
Development of Vocal Tract
• Right angle formed by the
cranialvertebral junction (angle of upper
throat where spine joins skull)
• Orientation of head & neck- vertical
• Base of cranium & vocal tract are bent
sharply relative to axis
• Bend is unique to humans
Development of Vocal Tract
• What does the shape of vocal tract preserve?
– Horizontal orientation of the special sense
organs (sight, smell, hearing) & feeding
apparatus
– Straight continuity between the brain stem and
the spinal cord
• Advantages:
– Completely close the nasal cavity while
maintaining an open oropharyngeal tract
• Human infants cannot close nasal tract
Development of Vocal Tract
• Neonatal:
– Born with nonhuman oropharyngeal anatomy
• Epiglottis high in the pharynx (touches soft palate)
• Larynx is positioned high
– Changes that occur:
• Larynx moves inferiorly, away from tongue and soft palate
• Epiglottis moves inferiorly
– Advantages of early oropharyngeal anatomy
• Allows respiration and feeding to occur simultaneously
Vocal Tract
Nasal
Cavity
Soft
Palate
Oropharynx
Laryngopharynx
Nasal
Cavity
Oral
Cavity
Vocal
Folds
Trachea
Oral
Cavity
Cavities
Nasopharynx
Oral Cavity
Oropharynx
Laryngopharynx
Cavities
• Major subdivisions of the vocal tract
that participate in articulation:
– Pharyngeal Cavity (throat)
– Nasal Cavity (nose)
– Oral Cavity (mouth)
Oral Cavity
• Extends from the oral opening, or mouth, in front
to the faucial pillars in back
• Oral opening involved in articulation
• Hard palate= hard roof or your mouth
– Rugae- prominent ridges running laterally (formation
of bolus)
– Median raphe- divided hard palate in half
• Soft Palate or Velum= Soft portion running behind
the hard palate
– Uvulus terminates soft palate
Oral Cavity
• Velum= movable muscle mass; separates oral &
nasal cavities
– Attached in front to the palatine bone
• Anterior & Posterior Faucial Pillars
– either side of soft palate, mark posterior margin of the
oral cavity
– Teeth and alveolar ridge of maxillae make up lateral
margins
• Palatine tonsils
– Between the Ant. & Post. faucial pillars
Oral Cavity
Rugae
Hard Palate
Median
Raphe
Velum
Uvula
Anterior Faucial
Pillar
Palatine
Tonsils
Posterior Faucial
Pillar
Pharyngeal Cavity
• Pharynx (3 regions)
– 12 cm in length
– Extends from the vocal folds blow to the region
behind the nasal cavities, above
– Tube is lined with muscle capable of
constricting to facilitate deglutition (also closes
velopharyngeal port)
• Velopharyngeal port- Opening between the
oropharynx and nasopharynx
Pharyngeal Cavity
• 3 regions:
– Oropharynx
• Portion of pharynx posterior to fauces, bounded above by
velum
• Lower boundary is the hyoid bone
– Laryngopharynx
• Bounded anteriorly by the epiglottis
• Inferiorly by the esophagus
– Nasopharynx
• Space above soft palate
• Bounded posteriorly by the protuberance of occipital bone
• lateral wall contains the orifice of Eustachian tube
Pharyngeal Muscles
• 3 large, thin muscles wrap around the
sides and back wall of the pharynx
– Inferior Constrictor
– Cricopharyngeus
– Middle Constrictor
– Stylopharyngeus
– Salpingopharyngeus
– Superior Constructor
Pharyngeal Muscles
Functions:
Superior
Constrictor
Middle
Constrictor
Inferior
Constrictor
1. NonspeechSwallowing-Mash food
-Major function to
shoot food into
esophagus
2. SpeechNarrowing pharynx,
Velopharyngeal
closure
Constrictor Pharyngis Inferior
* Level of laryngopharynx
* Origin: Sides of cricoid cartilage
anterior & lateral arch, fibers run
in a semi-circle
* Insertion: Dorsal pharyngeal midline raphe
Constrictor Pharyngis Medius
* Level of oropharynx
* Origin: Portion of hyoid
bone, wraps around
* Insertion: Midline raphe
Constrictor Pharyngis Superior
* Level of nasopharynx
*Origin: Very complex,
lots of bones of skull,
mandible, sides of tongue
* Insertion: Midline raphe
Stylopharyngeus
* Function: Will pull pharynx upward
& outward, expands pharynx
* Origin: Styloid process of temporal
bone, runs down
* Insertion: Fibers of the medial &
superior constrictors
Salpingopharyngeus
Origin: Eustachian tube (communication between pharynx
& middle ear)
Eustachian Tube
Salpingopharyngeus
Insertion: Pharyngeal walls
Function: thought to be involved in VP closure
Salpingopharyngeus
Salpingopharyngeus
Nasal Cavity
• Produced by paired maxillae, palatine
and nasal bones
• Divided by the nasal septum
• Made up of vomer bone, perpendicular
plate of ethmoid and cartilaginous
septum
• Nasal cavities & turbinates are covered
by mucous membrane
Nasal Cavity
• Air entering nasal cavity is warmed &
humidified to protect lungs
• Fine nasal hairs prevent particulate matter
from entering the lower respiratory
passageway
• Epithelia propel pollutants toward
nasopharynx where they are swallowed into
the esophagus
Nasal Cavity
• Nares or nostrils mark anterior
boundaries of the nasal cavities
• Nasal choanae are posterior portals
connecting the nasopharynx & nasal
cavities
• Floor of nasal cavity is the hard
palate
Nasal Cavity
Frontal Bone
Septal
Cartilage
Ethmoid
Perpendicular
Plate
Vomer
Anterior
Nasal Spine
Palatine Process
of Maxilla
Perpendicular
Plate of Palatine
Bone
Reading/Assignments
• Seikel: Pgs. 300-303; 326-330
• Dickson: Pgs. 202-207