Vocal Tract Tongue Face Muscles PDF

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Summary

Taught by Dr. Charles Larson...

Description

Oral cavity consists of two components: oral vestibule and oral cavity Mouth ● Refers only to the opening into the oral cavity (area bounded by the lips) ● Rima oris- orifice of mouth Oral vestibule ● Cavity lying between the inside of the lips and the outer surface of the teeth ● Bounded below and above by the gums, or gingiva ● Communicates with the oral cavity by small openings between the teeth (when teeth are closed) and by a space behind the 3rd molar. ● Frenulum ○ Midline fold of mucous membrane connecting lips to gums ○ Upper and lower ones ● Mucous membrane of the mouth is continuous with the skin at free margins of lips ● Labial glands ○ Lie underneath mucous membrane on inner surface of lips ○ Size of small peas ○ Secrete saliva into vestibule Oral cavity Bounded laterally and in front by the alveolar arches, teeth, gums. Bounded posteriorly by oropharyngeal isthmus ● opening between palatoglossal folds, aka anterior faucial pillars ○ fold encloses the palatoglossal muscle ● palatine tonsil is posterior to this fold ○ Posterior faucial pillar/palatopharyngeal arch encloses palatopharyngeal muscle ○ Collectively, arches form faucial arches; mark boundary between oral and pharyngeal cavities Bounded above by hard and soft palate ● Anteriorly, hard palate ends as alveolar ridge ○ Formed by palatine process of maxilla and horizontal plate of palatine bones ○ Separates oral from nasal cavities → chewing and breathing simultaneously ○ Covered with mucous membrane, and in the center is a midline called the raphe ● Mucous membrane is corrugated, and these folds are called rugae/plicae ● Soft palate: movable fold connected to posterior border of hard palate ○ Moveable → opening and closing of velopharyngeal port ■ Opening → nasal breathing, nasal sounds (m, n, ng) ■ Closing→ speech; swallowing ○ Covered by mucous membrane ○ Ends posteriorly as the uvula, a pendular extension ○ Soft palate (velum) connected laterally to oral cavity walls by faucial pillars

Bounded inferiorly by tongue dorsum ● Beneath tongue -- mucous membrane of tongue is continuous with gingiva ● Lingual frenulum: fold connecting tongue to floor of mouth in midline ● anterior 2/3 of tongue occupies oral cavity ○ Separated by pharyngeal part by sulcus terminalis -- V-shaped wedge ○ At apex is foramen caecum -- related to thyroid gland ● posterior 1/3 of tongue occupies oral pharynx ● On either side of line are papillae, which increase surface area ○ Taste receptors line papillae walls ○ Vallate papillae: largest type ● midline of tongue dorsum is marked by median sulcus Pharyngeal cavity ● Musculo-membronous tube that goes from larynx to nose ● Oral, nasal, laryngeal parts Nasopharynx ● Bounded rostrally by sphenoid bone and occipital bones ● Chonnae: 2 aperatures entering into nasal cavities from nasopharynx ● Bounded below by soft palate Posteriorally by posterior wall of pharynx ● Adenoid glands help remove bacteria and viruses from body Eustachian tube: pharyngeal orifice on lateral wall ● Channel connecting middle ear with pharynx ● Equalizes air pressure ● Bony part (12 mm long) + cartilaginous part (24 mm long) ● Goes upwards, backwards and lateral ● Shaped like a "C" -- open on one side ● Torus tubarious/salpingo fold: Cartilage forming ridge in nasopharynx ● Tensor veli palatini muscle helps open Eustachian tube ● Salpingopharyngeus muscle attaches near pharyngeal opening ● Levator veli palatini muscle runs alongside tube ● During deglutition and yawning, salpingopharyngeus and Tensor veli Palatini muscles contract, open the tube ● In children ○ Tube is short ○ Lies in a horizontal plane ○ Narrow opening into pharynx ○ Tube drains less easily, so middle ear problems are more common ● Isthmus: where bony and cartilaginous parts meet; narrowest and most likely to become obstructed ● bony part extends through the petrous part of temporal bone, opens onto anterior wall of middle ear

Oropharynx ● Bounded above by soft palate ● Bounded anteriorally by the faucial pillars (fauces) ● Bounded inferiorally at the level of the hyoid bone ● Bounded posteriorally by the pharyngeal wall ● Anterior wall of lower part is made up of posterior part of tongue----pharyngeal part 1/3 Laryngopharynx ● Bounded superiorally by hyoid bone ● Bounded below by esophagus ● Bounded anteriorally by larynx and aditis ad laryngis ● Bounded posteriorly by pharyngeal wall Tongue ● Muscular organ covered with mucous membrane ● Supported by muscles attached to the Hyoid bone, mandible, styloid process, and velum ● Mastication ○ Forms bolus ○ Positions it for efficient mastication ○ Pushes bolus into oropharynx for ingestion ○ Contains glands that secrete saliva for efficient mastication ● Speech ○ Alters shape of vocal tract in oral cavity and oropharynx to achieve different resonant sounds ○ Creates constrictions in vocal tract for production of consonants ○ Produces consent sounds by varying shape and size of constriction. ● Fibrous septum acts as a point of attachment for some muscles and comes closest to being a supporting framework in the tongue. ● Two sets of muscles ○ Intrinsic alters tongue shape ○ Extrinsic moves tongue within oral cavity ● Sulcus terminalis separates posterior 1/3 (pharyngeal) from anterior ⅔ (oral) part of the tongue ○ Foramen caecum at apex of sulcus ● Dorsum: upper surface of oral part of tongue ● Tip: portion nearest the front ○ Unattached; most mobile part of the tongue ● Blade: just posterior to tip; under alveolar ridge ● Front: under hard palate ● Back: under soft palate Source Filter Theory of Speech Production Speech Sounds ● Vowels are longer in duration, require less precision of articulation ● Consonants are shorter in duration, require greater precision of articulation than do vowels ● Some consonants, e.g.., glides, continuants, are longer in duration

8 Cardinal vowels ● Circumscribe extreme positions of tongue ○ Vowel quadrilateral describes articulatory positions of principal vowels ○ Most extreme points are defined by /i/, /u/, /a/ and [ah] ● Vowels also defined as high/low, front/back, tense/lax, close/open ● Central or neutral vowels = tongue in center, neutral position, little muscle action ● Speech articulations can be described with reference to tongue position and degree of constriction ○ Point of constriction can exist anywhere along vocal tract Consonants Type of Sound

Examples

Dental

/th/ /thhhh/

Alveolar Stop

/t/ /d/

Alveolar Fricative

/s/ /z/

Palatal

/ch/ unvoiced; /ch/ voiced

Palatal Fricative

/sh/ unvoiced; /sh/ voiced

Velar

/k/ /g/

Glottal

/h/

Alveolar Voiced Liquid

/l/

Palatal Voiced Liquid

/j/ /r/

Pathology ● Structural deficits: Dental, Palatal arch, Tongue atrophy, Congenital, Abnormal length, Short, unable to contact ridge, Long ● Neurological: ALS, Paralysis, Trauma, Dysarthria, Cerebral palsy, Cerebellar ataxia, PD, Dystonia, Diseases of the basal ganglia, Diseases of the extrapyramidal system, Myasthenia gravis ● Age-related changes: Muscle weakness, Slowness of muscle contraction, loss or death of motor neurons resulting in overall loss of muscle control ● Behavioral: hearing deficits, Poor modeling Facial Muscles ● Facial muscles, oftentimes, connect at least with one end of the muscle to soft tissue such as skin or mucous membrane ● function is to move skin - non-load bearing ● Facial muscles alter mouth shape ● variability in facial muscles from one person to another -- accounts for individual facial appearance

Lips ● ● ● ● ● ● ●

fleshy folds surrounding oral orifice outer skin and inner mucous membrane enclose muscle, vascular tissue, and salivary glands At each corner or angle of the mouth is the labial commisure In the middle of the upper lip, the shallow vertical groove is called the philtrum Adjacent to the philtrum are the columella, or slight raised folds of skin oriented in the vertical direction philtrum and columella extend from the lower border of the external nose to the lips Vermillion of lips contains protein eleidein - precursor to keratin ○ Gives translucent quality to lips. ○ Where the skin meets the vermillion is called the vermillion border ○ Cupid’s bow: curved part of vermillion border where philtrum meets upper lip

Face Muscles 1. Orbicularis Oris (OO) ● Orbicularis Oris Superior and Orbicularis Oris Inferior (OOS, OOI) ● Continuous ring that is wider than vermillion ● contains fibers from other facial muscles that blend in with OO muscle ● Close, purse, protrude, compresses lips ● Rounded vowels /o/ or /u/ 2. Buccinator - main muscle of cheek ● Fibers run horizontally across the side of the face ● O: pterygomandibular raphe -- ligament extending from hamulus to posterior portion of mylohyoid line has points of origin on alveolar process of maxilla and mandible ● covered by buccal fat pad ● I: mouth angle and terminate at points of insertion on the OO, or pass around rima oris with OO fibers ● Pulls corner of mouth laterally, compresses lips ● Assists in mastication by holding food between the teeth 3. Risorius -- not present in all people ● O: from fascia overlying masseter muscle ● Fibers run horizontally ● I: orbicularis oris fibers, skin of lips at mouth angle ● Retracts corner of mouth ● Laughing muscle 4. Levator Labii Superior Alaeque Nasi ● O: frontal process of maxilla and infraorbital margin ● Fibers descend in lateral direction - some insert on lateral nares ● I: insert into fibers of OO muscle - probably interdigitate with the OO muscle ● Dilates nostrils, elevates upper lip in a superior direction QUIZ REVIEW 1. As we change the shape and position of the tongue, we modify the size and shape of the cavities in the

upper vocal tract, which in turn alter the formant frequencies of speech sounds. 4. What are the names of the folds of tissue found on the lateral side of the oral cavity and connect the soft palate to the side of the tongue? faucial pillars 5. What is the name of the fold of tissue found on the lateral wall of the nasal pharynx? torus tubarious 6. What is the name of the ‘V’ shaped line on the dorsal surface of the tongue? median sulcus 7. Which facial muscle is important for pulling the angle of the mouth laterally as well as to assist the tongue in positioning food between the teeth for chewing? buccinator

CLASS NOTES Oral Cavity + Oral Vestibule = Oral Cavity 1. Oral cavity ● Hard and soft palate ○ Alveolar ridge -- important for /t/, /d/ ○ Palatal rugae ○ Many sensory receptors -- make fine adjustments ● Soft palate ○ Opening and closing of velopharyngeal port ○ Covered with mucous membrane ○ Ends at uvula -- may have a protective function ○ Connected to oral cavity via faucial pillars ○ Open → /m/, /n/, /ng/ ● ● ● ●

○ Close → prevent nasal breathing, speech, swallowing Anterior faucial arch Posterior faucal arch/palatal pharyngus Oral pharyngeal isthmus: opening into pharynx Tonsil: protect from bacteria, but are a source of infection if they accumulate too much

2. Oral Vestibule ● Between lips and teeth; bounded by gingiva ● Frenulum: midline fold of mucous membrane connecting tongue, gingiva ● Food bolus may fall in, but usually held between teeth 3. Pathology ● Tissue pathology -- abnormal size/position, lateral asymmetry ● Genetic factors

● Neural control mechanisms ● Palatal insufficiency ○ Short soft palate = too small to close velo-pharyngeal port ○ Causes nasal-y voice 4. Oral Cavity Boundaries ● Above = hard and soft palate ● Anterior = alveolar arch, gums, teeth ● Posterior = oropharyngeal isthmus ● Inferior = tongue dorsum Tongue 1. Major Parts ● Root ● Dorsum: center, conforms to hard palate ● Body ● Blade: on the sides, can flatten and curl it ● Apex: most anterior part 2. Superficial Features ● Palatine tonsil and lingual tonsil capture and break down bacteria ● Sulcus terminalis ● Foramen caecum: related to thyroid gland ● Papillae = bumps ○ Increase surface area → many taste receptors ○ Pits between papillae trap food -- better sense of taste 3. Innervation ● Front = CN 5 (trigeminal) ● Back = CN 9 (glossopharyngeal) Nasal Pharynx + Oral Pharynx + Laryngeal Pharynx = Pharyngeal Cavity 1. Nasal pharynx ● Choanne = anterior border

○ Adenoid tonsils -- enlargement distorts bone growth ○ Torus tubarious -- entry to Eustachian tube ● Hard palate = lower border 2. Oral pharynx ● Hyoid bone = lower border ● Soft palate = upper border ● Posterior part of tongue = anterior border 3. Laryngeal Pharynx ● Hyoid bone = upper border ● Upper esophageal sphincter = lower border ○ Opens during swallowing ● Epiglottis, aditus, pyriform sinus/recess = anterior border Acoustics Fourier ● You can represent any repeating wave as many sine waves ● Add up sine waves → glottal waves ● Fourier transform ○ Plots amplitude as a function of frequency ○ f0 = first frequency, tallest line ○ Harmonic frequencies (partials) = integer multiples of the f0, shorter lines ● Source is rich -- it has energy at many frequencies As f0 ↑, density of harmonic frequencies ↓ ● Related to energy -- not the same as loudness ● High density of harmonics = high energy Upper vocal tract = filter ● Resonating cavities ● Some frequencies don’t resonate; others do ○ Frequencies that don’t conform to resonating properties lower in amplitude ○ EX: nasal cavity lowers frequencies

● Formant: resonating frequency of vocal tract ● 3 resonating cavities = 3 formant frequencies ● Source sound is rich in frequencies → vocal tract modifies them into f1, f2, f3 ● We use articulators to change f1, f2, f3 -- vowels, diphthongs ● Consonants: start and stop ● Unvoiced sound: turbulence, not formants involved; but they do have some resonance Facial Muscles 1. Basics ● Stretch skin and mucous membranes ● Skin is flexible and elastic -- returns to its former position ● Cleft palate = facial tissues don’t come together ● Face is tough to dissect ○ Cut skin → cut muscle ○ Fatty tissue mixes with muscle fibers 2. Innervation ● Limbic system controls face for emotion ● Neurological disorders → loss of facial expression, as in Parkinson’s ● Voluntary NS for speech 3. Lips ● Enclose muscles, vascular tissue, salivary glands ● Vermillion color due to eleidin protein, which is a precursor to keratin ● Vermillion border: where skin and lips meet ● Labial commissure: where upper and lower lips come together ● Collumma: where tissue joins together on left and right sides of philtrum 4. Orbicularis Oris -- superior and inferior ● Continuous band of fibers that surround lips and attach to skin, vermillion, muscle ● Lip, mouth closure

● Very short fibers -- lots of ways to change lip shape ● Speech ○ Stops and plosives -- /p/, /b/ ○ Dentals -- /f/, /v/ ○ Lip rounding for /o/, /u/ -- lengthen vocal tract to change formant frequencies ● Eating -- contain food in the lips 5. Buccinator ● Runs horizontally across side of face ● O: pterygomandibular raphe -- ligament from hamulus to mylohyoid line ● I: OO muscles ● Pulls corners of mouth laterally, thus it is antagonistic to OO ● Compresses lips, holds food between teeth during mastication ● Speech: /w/ 6. Risorius ● “Laughing muscle” -- retracts mouth corners ● O: fascia over masseter ● I: OO fibers, lip skin at mouth angle 7. Levator labii superior alaeque nasi ● O: frontal process of maxilla & infraorbital margin ● I: lateral nares, OO muscle -- probably mix with OO fibers ● Descend laterally ● Helps with respiration -- flare nostrils ● Raises upper lip ● Release of bilabial stops/plosives - /p/, /b/ ● Open vowels...