lecture 18

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Supralaryngeal Anatomy &
Physiology
1
Velopharyngeal Anatomy
• Soft palate & its relationship with the
pharyngeal wall
• Muscles here run from skull and insert
somewhere in palate
• Muscles important for speech-Cleft palate
• Three sounds in English that require velum
to be depressed- n, m, ing
2
Soft Palate
• Velum; flexible muscular flap hanging from hard
palate
• Attached by the palatine aponeurosis
– Sheet of flattened tendon Arrangement of muscle
fibers:
• Elevates, lowers and tenses
• Three classes of muscles:
– Depressor relaxers (glossopalatine & Pharyngopalatine)
– Elevators (Levator Palatini & Uvular)
– Depressor-Tensor (Tensor Palatini)
3
Levator Veli Palatini
• Palatal Elevator, bulk of soft palate
• Arises from the temporal bone & medial wall
of the eustachian tube
• Courses down to insert into the palatal
aponeurosis of soft palate
• Primary elevator of the soft palate
– Contraction elevates & retracts the posterior
velum
4
Levator Veli Palatini
Temporal
Bone
5
Muscularis Uvulae
• 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
6
Tensor Veli Palatini
• Tensor of the soft palate and dilator of the
eustachian tube
• Arises from the sphenoid bone & lateral eustachian
tube wall
• Terminate into a tendon that wraps around the
pterygoid hammulus, then flattens to become the
palatine aponeurosis
• Contraction tenses the soft palate and flattens it &
dilates eustachian tube to aerate it.
7
Tensor Veli Palatini
Eustachian Tube
Hammulus
of Pterygoid
8
Soft Palate
Eustachian
Tube
Tensor
Palatini
Levator Palatini
Sagittal section of
Vocal tract 9
Palatoglossus
• Posterior of oral cavity
• Anterior faucial pillar (First arch in oral
cavity)
• Serves dual purpose:
– Elevates tongue or depresses soft palate
– Originates at the anterolateral palatal
aponeurosis & inserts into the sides of the
tongue
10
Palatoglossus
11
Palatopharyngeus
• Anterior fibers originate from the anterior
hard palate & posterior fibers arise from the
midline of the soft palate
• Insert into posterior thyroid cartilage
• Courses down and form posterior faucial
pillars
• Assists in narrowing the pharyngeal cavity &
lowers the soft palate & elevates larynx
12
Velar Depressors
Soft Palate
Palatine
Tonsil
Palatoglossus
Posterior
Faucial
Arch
Palatopharyngeus
Anterior
Faucial
Arch
13
Supralaryngeal Physiology
14
Introduction
• Source-filter theory
–Source = generates sound (larynx)
–Filter = sound modified (vocal tract)
• Vocal tract–Filter for all vowels and consonants
–Serves as source of noise for
consonants
15
Noise Generation: Source
• All consonants include an element of noise (except
semi-vowels)
• Consonant that is voiced= Noise added to the voice
generated at Glottal Source
• Consonant that is voiceless= Characterized entirely
by noise
• Narrowing of vocal tract causes resistance to cause
noise (usually in upper vocal tract)
– /h/ is an exception- noise caused at the glottis
16
Oral Pressure
• Two functions of vocal tract:
– Serves as a filter for all consonants & vowels
– Serves as a source of noise for most consonants
• Prerequisite for noise:
– Build pressure behind constriction or occlusion
• Intraoral air pressure (requires velopharyngeal
competence)
17
Turbulent Noise
• The noise element of consonants produced
by fricatives is the result of turbulence.
– Hiss of steam
– Occurs when air channel is constricted enough
to disrupt smooth flow of air
– Turbulence if the other type of consonant noise
(bursts & turbulence)
– Place of articulation distinguishes fricatives
18
Places of Articulation
K-G-NG
M-W-P-B
SH-ZHL-CH-J-R
TH T-D-S-Z-N
F-V
H
19
Bursts of Noise
• Burst, a puff of air
• Air stream is stopped by tongue or lips
(plosive or stop)
• Progress of stop:
– Closure (tongue, lips)-Block air stream
– Pressure builds behind stoppage
– Brief gap of silence
– Stoppage is released (can be aspirated)
20
Closure
Stoppage
Release
Transition
Airstream
Airstream
Stoppage
Transition
Silence
Plosive
Burst
Vowel
Typical Plosive Production
21
Reading/Assignments
• Seikel: Pgs. 323-326;
• Dickson: Pgs. 208-218
22
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