Articulatory System: Basic Anatomy Flashcards
Sound shaper
Articulators modify sound source into rapidly changing sounds recognized as speech
Shapes ACOUSTIC events
Sound produced eventually becomes perceptual events recognized as speech
Articulatory system basic biological functions
Smell
Taste
Swallowing
Warms, filters, and humidifies inhaled air
Articulatory system basic speech functions
Makes adjustments to vocal tract shape/size to change sound source into various speech sounds (formants and filter characteristics)
Articulators
Structures making adjustments in vocal tract
i.e. tongue, teeth, lips, velopharyngeal mechanism, etc…
Vocal tract
Double-barreled tube extending from the larynx (sound source) to mouth and nostrils
Made up of the pharyngeal cavity, nasal cavity, velopharyngeal port, hard palate, and oral cavity
Cavities
3 cavities of vocal tract:
1. Pharyngeal
2. Nasal
3. Oral
(Upper respiratory tract)
Pharyngeal cavity
3 sections:
1. Laryngopharynx
2. Oropharynx
3. Nasopharynx
Laryngopharynx
Section of pharyngeal cavity located at the laryngeal level
Links sound source to passageways to oral and nasal cavities
Oropharynx
Section of pharyngeal cavity located at oral cavity
Provides passageway for sound stream to enter oral cavity
Nasopharynx
Section of pharyngeal cavity located at nasal cavity
Provides passageway for sound stream to enter nasal cavity
Necessary for nasal consonants /m,n,ng/
Velopharyngeal mechanism overview
Most typical speech sounds, passageway between oropharynx and nasopharynx closed (velopharyngeal port closed) so that speech stream exits only through the oral cavity (Access to nasal cavity denied)
For nasal speech, passageway between oropharynx and nasopharynx momentarily opened, allowing speech stream to enter nasal cavity and not oral cavity (velopharyngeal port open). (Access to nasal cavity open briefly)
Velopharyngeal role
Closes velopharyngeal port, denies nasal cavity access for non-nasal sounds
Momentarily allows exhaled speech stream access to nasal cavity for nasal sounds
Key structure of velopharyngeal mechanism
Velum/soft palate
Flap of muscle (NOT BONE) with aponeurosis surrounding it called palatine aponeurosis
Located posterior to hard palate (maxilla and palatine bone)
Sits between the oral and nasal pharynx
Visible landmark: Uvula
Attachments:
Palatine bone
Surrounded by palatine aponeurosis
How does Velopharyngeal mechanism work?
Velum is pulled up and back against wall of nasopharynx by VP closers: Levator palatini (elevator) and uvula (stiffener)
Nasopharynx wall is constricted/tightened towards the velum by VP closer: Superior constrictor (constrictor)
(Together, results in VP closure)
Occasionally, Velum is lowered to allow nasal speech by VP depressors: Palatoglossus and Palatopharyngeus
(Results in nasal resonance)
Velum at rest
Breathing, it is OPEN so you can breath through nose
Velum at speech
Non-nasal: closed
Nasal: open briefly
Velopharyngeal closure error
When the velum doesn’t close securely:
Leaks air into the nasal cavity seen as bubbles
If bubbles seen, air flow is in nasal cavity where it should be constricted
Severely affects speech intelligibility
VP mechanism is VERY essential for both speech and swallowing processes
Nasal cavity functions
Speech: Alters quality of speech stream recognized as nasal characteristic
Biology: Warms, filters, and humidifies inhaled air, smell/taste, and breathing
Nasal cavity structure
Comprised of complex bilateral cavities each interconnected with sinuses of facial and cranial bones
Nasal septum
Bilateral cavities separated by:
Nasal septum (cartilage, Ethmoid bone, Vomer bone)
Ethmoid bone is upper half, vomer is lower half of the septum
Lateral walls of nasal cavity
3 parts:
1. Inferior nasal concha (facial bone)
2. Middle nasal concha (ethmoid bone)
3. Superior nasal concha (ethmoid bone)
Upper 2/3 ethmoid, lower 1/3 inferior nasal concha
All 3 are long, curly spongy bones that projects laterally into each nasal cavity, deeper than they appear
Hard palate function
Velopharyngeal closure closure for intelligible speech
Ensures exhaled air stream does not leak into nasal cavity (firm border)
Even if VP closes, if hard palate didn’t exist, air would flow into the nasal cavity
Hard palate structure
Comprised of:
Maxilla
Palatine bone
Maxilla
2 landmarks:
1. Premaxilla
2. Palatine process of maxilla bone
Palatine bone
1 Landmark:
1. Palatine process of palatine bone
What happens when integrity of hard palate is compromised?
Cleft lip/palate
Cleft lip: A cleft/break on the lips
Cleft palate: A cleft/break of the hard palate
Different types:
Incomplete unilateral cleft lip
Unilateral cleft lip and palate
Bilateral cleft lip and palate
Isolated cleft palate
Cleft palate cause
Lack of fusion between nasal septum, palatine bone, and maxilla bone
Cleft lip cause
Lack of fusion between premaxilla and the palatine process of maxilla bone
Oral cavity
Major role in shaping acoustic events into perceptual events
Oral cavity function
Speech:
Alters shape of vocal tract’s exit and contributes to facial expression
Biological:
Lip closure during chewing and swallowing
Tongue functions
Speech:
Rapidly alters shape of oral cavity by various extrinsic and intrinsic muscles, it changes it’s position and shape respectively
Mandible functions
Speech: Alters overall size of oral cavity, most notably for vowels but also consonants
Biological: Biting and chewing