Laryngeal Function and Speech Production Learning Objectives Describe the basic role of the larynx...
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- Slide 1
- Slide 2
- Laryngeal Function and Speech Production
- Slide 3
- Learning Objectives Describe the basic role of the larynx in
speech and song.
- Slide 4
- What is the basic role of the larynx in speech and song Sound
source to excite the vocal tract Voice Whisper Prosody Fundamental
frequency (F0) variation Amplitude variation Realization of
phonetic goals Voicing Devoicing Glottal frication (/ /, / /)
Glottal stop (/ /) Aspiration Para-linguistic and extra-linguistic
roles Transmit affect Speaker identity
- Slide 5
- Learning Objectives Possess a knowledge of laryngeal anatomy
sufficient to understand the biomechanics, aerodynamics and
acoustics of phonation.
- Slide 6
- SPPA 4030 Speech Science5 The hyo-laryngeal complex
- Slide 7
- SPPA 4030 Speech Science6 Extrinsic/Supplementary Muscles
- Slide 8
- SPPA 4030 Speech Science7 Intrinsic muscles
- Slide 9
- SPPA 4030 Speech Science8 Muscular Actions
- Slide 10
- SPPA 4030 Speech Science9 CA joint function
- Slide 11
- SPPA 4030 Speech Science10 Muscular actions on vocal folds
Alter position Adduction LCA, IA, TA Abduction PCA Alter tension
(and length) Increase/decrease longitudinal tension Balance between
TA and CT
- Slide 12
- SPPA 4030 Speech Science11 Extrinsic/supplementary muscles
Holds the larynx in the neck Allows positional change of the larynx
Elevates when swallowing Elevates during certain speech activities
Elevating pitch High vowel production
- Slide 13
- SPPA 4030 Speech Science12 The larynx
- Slide 14
- SPPA 4030 Speech Science13 Layered structure of vocal fold
- Slide 15
- SPPA 4030 Speech Science14 Basic Structure of the vocal fold
epithelium connective tissue superficial layer tissue loosely
connected to the other layers intermediate layer elastic fibers
deep layer collagen fibers (not stretchy) muscle (TA) Vocal
ligament Lamina propria
- Slide 16
- The vocal fold through life Newborns No layered structure of LP
LP loose and pliable Children Vocal ligament appears 1-4 yrs
3-layered LP is not clear until 15 yrs Old age Superficial layer
becomes edematous & thicker Thinning of intermediate layer and
thickening of deep layer Changes in LP more pronounced in men
Muscle atrophy
- Slide 17
- Learning Objectives Describe the control variables of laryngeal
function.
- Slide 18
- Laryngeal Opposing Pressure Pressure that opposes
translaryngeal air pressure Sources Muscular pressure Surface
tension Gravity
- Slide 19
- Laryngeal Airway Resistance (LAR) Components of LAR
Translaryngeal pressure Translaryngeal flow Values can vary widely
Resistance=Pressure/Flow
- Slide 20
- Glottal Size
- Slide 21
- Vocal Fold Stiffness
- Slide 22
- Effective Mass and Length
- Slide 23
- Learning Objectives Outline and briefly describe the different
types of sounds that can be produced by the larynx.
- Slide 24
- Laryngeal Sound Generation Transient vs. Continuous Glottal
stops Aperiodic vs. Periodic Glottal fricatives Whispering Voice
production/phonation
- Slide 25
- Laryngeal Sound Generation Glottal stop Glottal fricative
- Slide 26
- Learning Objectives Describe a single cycle of vocal fold
oscillation Describe why phonation is considered quasi- periodic
Describe the relationship between vocal fold motion (kinematics),
laryngeal aerodynamics and sound pressure wave formation Describe
and draw idealized waveforms and spectra of the glottal sound
source
- Slide 27
- Complexity of vocal fold vibration Vertical phase difference
Longitudinal phase difference
- Slide 28
- The Glottal Cycle
- Slide 29
- Phonation is actually quasi-periodic Complex Periodic vocal
fold oscillation Aperiodic Broad frequency noise embedded in signal
Non-periodic vocal fold oscillation Asymmetry of vocal fold
oscillation Air turbulence
- Slide 30
- Flow Glottogram
- Slide 31
- Synchronous plots Sound pressure waveform (microphone at mouth)
Glottal Airflow (inverse filtered mask signal) Glottal Area
(photoglottogram) Vocal Fold Contact (electroglottogram)
- Slide 32
- Sound pressure wave Time Instantaneous sound pressure
- Slide 33
- Learning Objectives Explain vocal fold motion using the 2-mass
model version of the myoelastic- aerodynamic theory of
phonation
- Slide 34
- Glottal Aerodynamics: Some Terminology Subglottal pressure
Translaryngeal Pressure (Driving Pressure) Translaryngeal Airflow
(Volume Velocity) Laryngeal Airway Resistance Phonation Threshold
Pressure Initiate phonation Sustain phonation
- Slide 35
- Myoelastic Aerodynamic Theory of Phonation Necessary and
Sufficient Conditions Vocal Folds are adducted (Adduction) Vocal
Folds are tensed (Longitudinal Tension) Presence of Aerodynamic
pressures (driving pressure)
- Slide 36
- 2-mass model Lower part of vocal fold Upper part of vocal fold
Mechanical coupling stiffness TA muscle Coupling between mucosa
& muscle
- Slide 37
- Definitions of terms P me : myoelastic pressure (aka laryngeal
opposing pressure) P sg : subglottal pressure P atm : atmospheric
pressure P wg : pressure within the glottis U tg : transglottal
(translaryngeal) airflow
- Slide 38
- VF adducted & tensed myoelastic pressure (P me ) Glottis is
closed subglottal air pressure (P sg ) P sg ~ 8-10 cm H 2 0, P sg
> P me L and R M1 separate Transglottal airflow (U tg ) = 0 As
M1 separates, M2 follows due to mechanical coupling stiffness P sg
> P me glottis begins to open P sg > P atm therefore U tg
> 0
- Slide 39
- U tg since glottal aperature