Week 7+8 Anatomy Articulation (and tongue muscles)

FINAL EXAM https://create.kahoot.it/share/anatomy-of-articulation/e723d846-a040-4b96-9599-7ea86ccb7ef0

What 3 parts can the vocal track be divided in?

What 3 parts can the vocal track be divided in?

– Pharynx
– Nasal tract
– Oral tract (tongue, teeth, lips, jaw)

Many different (big and small) structures, muscles and ligaments are involved in the production of speech

What is articulation for speech?

– Process of bringing two or more moveable speech structures together to form the sounds of speech

– In the oral cavity, the undifferentiated buzz produced by the vocal folds (i.e. the source signal) is shaped (manipulated) into phonemes

What’s the source-filter theory of vowel production?

• Describes how oral cavity shapes speech

  • States that a voicing source is generated by vocal folds, routed through vocal tract, and then shaped into sounds of speech

• Vocal tract consists of the oral cavity, pharynx, and nasal cavity

• This linkage provides the variable resonating cavity that produces sound

Which structures are used to produce sounds of speech?

May be mobile

• Tongue, mandible (lower jaw), velum (soft palate) lips, cheeks, pharynx, larynx, and hyoid bone

May be immobile

• Teeth, hard palate, alveolar ridge of the maxillae (upper jaw)

What’s the Oral Cavitiy?

• Most significant of the cavities

• Undergoes most change during speech act

• Strongly involved in articulation

• Shaped by movements of tongue and mandible

What are the Cavities of the Vocal Tract (5)?

• Hard palate - hard roof of the mouth

  • Rugae - prominent lateral ridges

  • Median raphe - divides hard palate in half

• Velum - soft palate - soft roof of mouth - movable muscle that separates oral and nasal cavities

• Uvula - terminus of soft palate

• Anterior and posterior faucial pillars - sides of the velum

• Palatine tonsils - between faucial pillars

What’s the Buccal cavity?

• Plays a role in oral resonance and high level consonant production

• Lies lateral to oral cavity between teeth and cheeks

What’s the Pharyngeal cavity (pharynx)?

• Shape altered by pharyngeal constrictor muscles, laryngeal elevation and depression

• Types of pharyngeal cavities:

  • Oropharynx - posterior to fauces, above is velum

  • Laryngopharynx (hypopharynx) - anterior epiglottis, inferior esophagus

  • Nasopharynx - above the soft palate, contains pharyngeal tonsils (adenoids); lateral wall contains Eustachian tube – aerates the middle ear

• Velopharyngeal port (VPP) - opening between oropharynx and nasopharynx

What are the functions of the Nasal cavities?

• Warms and humidifies air to protect the lungs

• Fine nasal hairs prevent particles from entering lower respiratory tract

• Nares - anterior boundary; floor is hard palate (nasal passage)

• Nasal choanae - posterior portals connecting nasopharynx and nasal cavities

What are the muscles of the face & mouth?

• Tongue & mouth muscles

  • Tongue & Velum

• Lips and lip muscles

  • Movement for speech depends on muscles of face

  • Important in both facial expression and speech

  • Richly invested with vascular supply

  • Have social, cultural and aesthetic value

• Mandible muscles

What’s the functions of the lower lip? (6)

• Faster and stronger than the upper lip

• Achieves a greater velocity and force

• Does most of the work in lip closure

• Attached to the mandible—a movable articulator

• Can accommodate a variety of jaw positions

• Resistant to interference

What are the lip muscles? (7)

• Obicularis oris - encircle mouth opening

• Risourius- superficial - retracts corner of mouth

• Buccinator - deep to risourius, retracts corner of mouth, involved in mastication

• Levator labii superioris, zygomatic minor, levator labii superioris alaeque nasi - elevate upper lip

• Levator anguli oris - draw mouth up and medially

• Zygomatic major - elevate and retract angle of the mouth – smiling

• Depressor labii inferioris - pull lip down and out

**Label the mandible structure**

What are the roles of the mandible?

• Plays a role in speech (-> jaw opening and closing)

  • Assists the lips - important supportive role

  • Changes position for tongue movement

  • Can tightly close when necessary

  • Position for speech is one of dynamic tension between antagonists

• Mandibular elevator muscles have muscle spindles

  • Helps to counteract gravity

• Plays major role in mastication

  • Central pattern generator within brainstem

    • Produces muscular contraction for chewing

    • Must elevate, grind laterally, and depress

      • Requires coordinated activation of elevators and depressors

What are the mandibular elevators? (3)

• Masseter - elevates mandible

• Temporalis - elevates mandible (and retracts)

• Medial pterygoid - elevates mandible

What are the mandibular depressors? (4)'

• Digastricus (anterior and posterior - depress mandible

• Mylohyoid - depresses mandible if hyoi fixed

• Geniohyoid - depresses mandible if hyoid fixed

• Platysma

What’s the velum?

• Referred to as the soft palate

  • Performs wide range of movements

  • Production of most speech sounds

    • Must remain in a moderately elevated position (for non-nasal sounds)

• Non-nasal speech: Velum generally remains closed (velum raised)

• Velum is closed for non-nasalized speech

  • Muscle function for closing: Levator veli palatini (most important one)

  • Assimilation - some nasal quality to adjacent phonemes

  • High pressure consonants (fricatives and stops) require greater velopharyngeal closure

• Hard and soft palate are endowed with sensors

• Uvula is part of the velar structure (hangs from the end of the soft palate)

Hypernasality

excessive nasal resonance due to inadequately closing velum

Hyponasality

absence of nasalized speech in nasal sounds such as /m/ and /n/ due to inadequate velopharyngeal (VP) opening

Nasal tract and velum interaction

• Upper part of the nasopharynx merges into the nasal tract and ends at the nose

• Biological functions:

  • Warming of the inhaled air while breathing

• All surfaces are covered by mucous membranes

Whats the coupling to the oral tract?

Connection to oropharynx is achieved by lowering the velum -> this process opens the velopharyngeal port (VPP)

What’s Sound propagation in the nasal cavity?

• The Nasal tract cannot produce speech sounds by itself -> but in connection to the rest of the vocal tract (connected or not connected) it can alter acoustic properties of speech sounds considerably -> coupling nasal tract is achieved by lowered or raised velum (lowered velum = nasal cavity coupled; raised velum =

  nasal cavity not coupled -> not active in speech production)

• Nearly no sound energy leaves the nasal tract -> due to small openings plus high damping (reason: the mucous walls)

• rather the nasal cavity “draws” energy away from the sounds that are produced and modified in the oral tract

Explain the velum muscles

• Muscles of velum compress to elevate the velar structure to completely separate oral and nasal areas -> thus preventing the nasal cavity to be coupled to the oral cavity

• Muscles are compressed during most speaking time and when swallowing

• Muscles not compressed only when using a few speech sounds in English – nasals

  • In other languages velum is opened for both nasal phonemes and nasal(ized) vowels

Explain the strucure of the pharynx

• The top of the larynx joins with the esophagus at the laryngopharynx (area above the larynx)

• The most superior part of the epiglottis marks the beginning of the oropharynx

• The area above the velum is the nasopharynx

• The pharynx is a four-way crossing: nasal tract, oral tract, larynx and esophagus → Esophagus is used during swallowing and eating (epiglottis closed)

Can the tongue muscle cover almost the complete available articulatory space?

Yes

How’s the tongue divided into

• tongue tip (apex)

• tongue blade

• tongue dorsum

• tongue back

• tongue root

How are the tongue muscles categorized?

• Intrinsic muscles

  • the origin and insertion are both found inside the tongue structure

  • responsible for precise articulatory performance

• Extrinsic muscles

  • attachment to structures outside of the tongue (e.g. hyoid bone or styloid process)

  • tends to move the tongue as a unit

• they set the general posture for articulation, with the intrinsic muscles performing the refined perfection of that action.

How are the tongue muscles innervated?

by the hypoglossal nerve (XII)

What are the 3 types of intrinsic muscles and their function, origin & POI?

• Superior longitudinal muscle: elevates tongue tip

• Inferior longitudinal muscle: depresses tongue tip

• Verticalis: pulls tongue down into floor of mouth

What are the 5 types of extrinsic muscles and their function, origin & POI?

• Genioglossus Anterior: Retraction of the tongue

• Genioglossus Posterior: Protrusion of the tongue

• Hyoglossus: Pulls (side of) tongue down

• Styloglossus: Retract and elevate tongue

• Palatoglossus: Elevation of the (posterior) tongue (only one innervated by Glossopharyngeal (IX) & Vagus (X) )