Articulatory System: Physiology Flashcards
Source filter theory
- Sound source (V+ or V-) from larynx
- Filter (vocal tract modifies sound source)
2.5. Noise source (vocal tract can also be new “source” of noise)
- Speech sound (what we perceive as speech)
What is a filter?
Tubes= filter
Every “tube” or filter has a natural HZ that they highlight/emphasize/resonate with when a sound is passed through them
Other Hz, they downplay
How does vocal tract act as a filter?
When you introduce a complex glottal sound to one end of a vocal tract, the vocal tract filters the frequencies by highlighting resonant Hz.
Results in sound exiting other end of vocal tract as filtered version of complex sound. This filtered sound= recognized as speech!
These highlighted Hz are called formants (frequency peaks) that make speech sounds identifiable
Vocal tract constantly changes shape during speech, resulting in changes of natural resonant Hz constantly
Results in continually different filtered sounds (Speech)
Vocal tract is highly malleable tube that continually filters complex sounds into perceived speech
What is the vocal tract?
Flexible, durable, double-barreled tube that can rapidly change chape with 3 cavities
What ways can the 3 cavities be modified in?
- Pharyngeal cavity: Length and diameter
- Oral cavity: Shape and opening
- Nasal cavity: added or subtracted
Modifications leads to highlighting different pitches, noise source, or nasal quality respectively
Modifying pharyngeal cavity
Basics:
1. Assume voiced glottal source for ease
2. Assume nasal cavity subtracted for ease
3 ways to modify pharyngeal cavity:
1. Length
Lengthen or shorten
2. Diameter
Narrow or widen
3. Combination
Rule of thumb formants
Smaller cavity: highlights higher Hz
Larger cavity: highlights lower Hz
Lengthening pharyngeal cavity
Lowering the larynx via infrahyoid muscles
Results in larger cavity, highlighting lower Hz
Remember, when larynx goes down, lower Hz
Shortening pharyngeal cavity
Raising the larynx via suprahyoid muscles
Results in smaller cavity, highlighting higher Hz
Narrowing pharyngeal cavity
Constricting pharyngeal walls via the pharyngeal constrictors
Results in smaller cavity size, highlighting higher Hz
Widening pharyngeal cavity
Widening pharyngeal walls via relaxing the constrictors, or with stylopharyngeus
Results in larger cavity, highlighting lower Hz
Combination of length and diameter of pharyngeal cavity
Shorter and narrower: Highest Hz
Longer and wider: Lowest Hz
Theory of vowel production
Basics:
1. Assume voiced glottal source since all vowels are voiced
2. Assume nasal cavity subtracted since all vowels in English are not nasal
2 ways oral cavity is modified:
1. Shape of oral cavity via tongue and mandible position
2. Shape of exit via lip and mandible position
Oral cavity changes create the formants for vowels
Vocal tract reimagined
Rethink oral cavity as a curved open tube of air ignoring all muscles and bones can be change in shape in combination with pharyngeal cavity
Same as actual vocal tract
Modifying oral cavity for vowels
3 ways:
1. Vertical jaw/tongue placement
Height: high/low
2. Horizontal tongue placement
Front/back
3. Lip rounding
Rounded/unrounded
/i/
High, front tongue
unrounded
Muscles:
Vp closers: Levator palatini and Superior constrictor
Tongue: Geniohyoid, mylohyoid, digastric (anterior), Vertical (flatten),
Lips: Risorius
/u/
High and back tongue
rounded
Muscles:
Vp closers: Levator palatini, superior constrictor
Tongue: Palatoglossus, styloglossus
Lips: Orbicularis oris, incisivus labii superior/inferior
/a/
Low and back tongue
unrounded
Muscles:
Vp closers: Levator palatini, superior constrictor
Tongue: Hyoglossus, vertical (flatten)
Mandible: Mylohyoid, geniohyoid, digastric (anterior) (depressors)
Theory of consonant acoustics
Glottal source from larynx either voiced or voiceless
Supraglottal filters sound source or acts as a new noise source
Vocal tract for consonants divided into:
1. Nasals (nasal resonance)
2. Fricatives (turbulence)
3. Stops (noise burst)
Nasal production
Nasal characteristic produced by adding nasal cavity to vocal tract and closing oral exit for nasal resonance
Basics:
1. Voiced sound source
2. Nasal cavity added
3. Oral cavity exit blocked
Shape of open nasal cavity
Remains same for all nasals
Anti-formants
Since oral cavity is an obstructed filter, it DAMPENS instead of highlighting frequencies
Smaller cavity: dampens higher Hz
Larger cavity: dampens lower Hz
These dampened Hz are called anti-resonance, anti-formants
Rule of thumb antiformants
Smaller cavity: dampens higher Hz
Larger cavity: dampens lower Hz
Shape of closed oral cavity
Size of closed oral cavity affects filter characteristics that differentiate nasals
/m/: Large closed oral cavity, dampens lower Hz
/n/: Medium closed oral cavity, dampens middle Hz
/ng/: Smallest closed oral cavity, dampens higher Hz
/m/
Muscles:
Vp open: Palatopharyngeus, Palatoglossus
Lip: Orbicularis oris, buccinator
/n/
Vp open: Palatoglossus, palatopharyngeus
Tongue: Mylohyoid, geniohyoid, digastric (anterior), superior longitudinal
/ng/
Vp open: Palatoglossus, palatopharyngeus
Tongue: Palatoglossus, styloglossus
Vocal tract as noise source
2 different ways:
1. Adding hissing noise by creating turbulence in speech stream by narrowing airway (fricatives)
2. Adding popping noise by noise bursts created by momentarily blocking speech stream then releasing it (stops)
Vocal tract not just a filter: can also be a noise source!
Fricative production
Fricatives produced by using vocal tract to create turbulence.
Turbulence created by narrowing airflow
Turbulence adds hiss-like acoustic quality to speech stream
f,v,th,eth,s,z,sh,ezh,h
Basics:
1. Glottal sound source can be voiced or voiceless
2. Nasal cavity subtracted
3. Fricatives produced by passing speech stream though narrow tract, causing turbulence
3.5. Sometimes, additional turbulence created via obstacles (sibilants)
Size of cavity in front of narrow constriction
Influences fricative characteristics by highlighting certain formants, making them identifiable
Same rule as formants
Smaller cavity in front of constriction: highlights higher Hz
Larger cavity in front of constriction: highlights lower Hz
Examples:
Labiodentals and dentals have little to no space in front of constriction: exempt
Most sibilants apply
/s,z/ have less cavity in front of constriction because lips are not protruded and constriction is at alveolar ridge
Highlights higher Hz due to smaller cavity
/sh,ezh/ have more cavity in front of constriction because lips are protruded and constriction is post-alveolar ridge
Highlights lower Hz due to larger cavity
3 modifications that change fricatives
- Glottal sound source
- Place of constriction/articulation
- Edge of obstruction
- Glottal sound source modification
Voiced: v,z,ezh,eth
Voiceless: f,s,sh,th
- Place of constriction/articulation
Labiodentals /f,v/:
Lower lip and upper teeth
Muscles:
Vp closers: Levator palatini, superior constrictor
Lips: orbicularis oris
Dentals /th,eth/:
Tongue tip between teeth
Mucles:
Vp closers: Levator palatini, superior constrictor
Tongue: Mylohyoid, geniohyoid, digastric (anterior), genioglossus
Alveolars /s,z/:
Tongue raised and grooved at alveolar ridge
Muscles:
Vp closers: Levator palatini, superior constrictor
Tongue: Mylohyoid, geniohyoid, digastric (anterior), genioglossus
Post-alveolars /sh,ezh/:
Tongue arched up and flat and curled down, constriction more back than regular alveolar
Muscles:
Vp closers: Levator palatini, superior constrictor
Tongue: Mylohyoid, geniohyoid, digastric (anterior), inferior longitudinal, vertical
Lips: orbicularis oris, incisivus labii superior/inferior
- Edge of obstruction modification
2 types:
1. Sharp edge
Teeth
More turbulent, hissing
- Broad edge
Flat tongue
Less turbulent
Examples:
/s,z/:
Sharp edge of obstruction first
Teeth
Higher Hz sounds
/sh,ezh/:
Broad edge of obstruction first
Flat of tongue
Lower Hz sounds
When you lose 2 front teeth, the /s/ is not as sharp or high Hz and sounds more like /sh/ because sharp edge turned to broad edge
Stops/plosives production
Characteristic sound produced by momentarily occluding and suddenly releasing speech stream
Occlusion and release adds pop-like acoustic quality called noise-bursts
p,t,k,d,b,g
Basics:
1. Glottal sound either voiced or voiceless
2. Nasal subtracted
3. Stop sound produced by brief 1/10th of a second blocking speech stream leading to momentary build up of pressure followed by sudden release (noise burst)
3.5. Some stops may include closure interval followed by aspiration; for voiceless stops only
Size of cavity in front of occlusion
Affects resonance characteristics, same rule of thumb
Examples:
Bilabial /p,b/:
No cavity: exempt
Alveolar /t,d/:
Small cavity in front of occlusion, emphasizes higher Hz
Velar /k,g/:
Larger cavity in front of occlusion
emphasizes lower Hz
Modifications of stop sounds
- Glottal sound source modification
- Place of occlusion/articulation
- Glottal sound source modification (stops)
Voiced: b,d,g
Voiceless: p,t,k
- Place of occlusion/articulation
Bilabial /p,b/:
Occlusion with lip compression
Muscles:
Vp closers: Levator palatini, superior constrictor
Lip: Orbicularis oris, buccinator
Alveolar /t,d/:
Occlusion with tongue tip behind teeth
Muscles:
Vp closers: Levator palatini, superior constrictor
Tongue: Mylohyoid, geniohyoid, digastric (anterior), genioglossus, superior longitudinal
Velar /k,g/:
Occlusion with tongue dorsum and velum
Muscles:
Vp closers: Levator palatini, superior constrictor
Tongue: Styloglossus, palatoglossus
Voice onset time (VOT)
Measurable sound characteristic related to stops and phonation
Closure followed by burst, VOT, aspiration, then glottal cycle
Whisper
Voiceless glottal source with same vocal tract filter as regular speech
Results in recognizable speech comprised ONLY on turbulence
Coarticulation overview
From an anatomical perspective, we are fast talkers with slow moving equipment (articulators)
Example:
We produce 6 syllables/second, 10/12 sounds/second
pataka x2
We cannot achieve this speech if we open/close our mouths, fully articulating each sound
Coarticulation
Shows us how we are able to talk so fast yet our articulators move so slow
Mutual influence of one sound on neighboring sounds
2 types:
1. Anticipatory coarticulation
2. Carry-over coarticulation
- Anticipatory coarticulation
Characteristic of a sound is prepared for production prior to actual production
ex. SUE and SEE
by /s/, lips are either rounded or spread prior to the vowel
Possible because /s/ sound is not influenced by lip rounding
Demonstrates how we are fast talkers
- Carry-over coarticulation
When characteristic of a sound continues to be produced even after it is said
ex. NO and TOOTS
the nasal quality carries over to the vowel, and the roundedness carries over to /ts/
Shows how articulators can be slow moving
