S/H sciences ~ exam 2

Speech breathing

regulation of breathing for voice and speech production

Respiration

process of gas exchange

the biological basis for breathing

Boyles law

if the volume of a gas is increased, the pressure will decrease

air flows from high pressure areas to low pressure

What are the pressure changes during boyles law

-During inspiration: you expand your lungs (increase volume) causing a decrease in pressure (aka negative pressure)

- During expiration you contract your lungs (decrease volume) causing an increase in pressure (aka positive pressure)

Muscles

muscles are contractile tissues

contraction is the only active movement of a muscle

Agonist

the muscle that contracts

Antagonist

a muscle that opposes the contraction of the agonist

A muscle is an _____ in one motion and an ______ in the opposite motion

agonist, antagonist

Agonist can be a ____ _____ OR ______

prime mover, synergist

Concentric tension load

tension > load

muscle shortens

Isometric tension load

tension = load

muscle stays the same length

Eccentric tension load

tension < load

muscle lengthens

Muscles of inspiration

diaphragm

external intercostals

muscles of expiration

internal intercostals

Where is the diphragm?

attached to the spinal column and lower ribcage

Where are the External intercostals?

extend from the lower aspect of one rib to the upper aspect of the rib below

Where are the internal intercostals?

connects ribs to one another

What does the diaphragm look like?

convex shaped at rest with dome pointing upward toward lungs

What do the external intercostals look like?

series of short-fibered muscles

What do the internal intercostals look like?

thin sheets of muscle

What does the diaphragm do when it contracts?

flattens downward and spreads outward and anteriorly

What do the external intercostals do when they contract?

elevate the rib cage

What do the internal intercostals do when contracted?

depress the rib cage and draw it inward

What are the lung capacities?

Total lung capacity (TLC)

Vital capacity (VC)

Functional residual capacity (FRC)

What are the lung volumes?

Tidal volume (TV)

Residual volume (RV)

Inspiratory reserve volume (IRV)

Expiratory reserve volume (ERV)

Relaxation curve

charts the pressure generated by elastic recoil forces at different percentages of the VC

Transthoracic pressure

???

______. ______. _______ = approx. 38% of vital capacity

resting lung volume

Inspiratory checking

counteracts relaxation pressures and promotes steady lung pressure necessary for phonation

When does inspiratory lung pressure occur?

only used when the lung pressure is greater than necessary to sustain phonation

Phonation

generation of sound by means of vocal fold vibration

Glottal volume velocity

volume of air flowing through the glottis during phonation as a function of time

Laryngeal airway resistance

measure of the amount of resistance the VF offer to the airflow

3 functions of the larynx

phonation

stabilization of the trunk

protection of the airway from foreign substances

3 paired cartilages of the larynx

arytenoids, corniculates, cuneiforms

3 unpaired cartilages of the larynx

cricoid, thyroid, epiglottis

Cartilages are connected by ______ and covered by ______

ligaments, membranes

Hyaline cartilage

begins to ossify in later years

cricoid, thyroid, arytenoids

Elastic cartilages

remains flexible throughout life

epiglottis, corniculates, portions of arytenoids

_______. ________ connect the laryngeal cartilages to each other

intrinsic muscles

Types of intrinsic muscles

adductors, abductors, tensors, vocal folds

Adductors

lateral cricoarytenoid (LCA)

transverse and oblique interarytenoid (IA)

Abductors

posterior cricoarytenoid (PCA)

Tensors

Cricothyroid (CT)

Vocal folds

thyroarytenoid (TA)

paired structure

Where do the vocal folds attach?

thyroid notch and arytenoids

CN intervention of intrinsic muscles

???

VF are _______ folds of ______

multilayered, tissue

Tissue layers of the VF

epithelium

superficial lamina propria

intermediate lamina propria

deep lamina propria

Physical properties of the epithelium

thin layer & pliable

Physical properties of superficial lamina propria

loosely arranged elastin fibers

gelatin like

very mobile and easily stretched

Physical properties of intermediate lamina propria

elastin fibers but more densely arranged, collagen fibers

Physical properties of the deep lamina propria

densely arranged collagen fibers

How are the VF tissue layers grouped in different models

3 mechanical layer model:

mucosa, transition, body-cover

Myoelastic-aerodynamic theory

experiments demonstrated two phenomena:

adducting VF into airstream causes them to vibrate

increasing tension of VF causes the rate of vibration to increase

Bernoulli effect

the pressure exerted by a fluid on a surface decreases as the velocity of the fluid increases

faster velocity = lower pressure above the wing, causing an upward lift force

Venturi effect

fluid has to travel faster through a narrowed area

reduced pressure when flowing through a constricted area

How does bernoulli and venturi relate to VF vibration?

-vibration is dependent on the airstream

-lung pressure and the bernoulli effect draws the VF into vibration

-transglottal drop in pressure sustains oscillation (passive process)

Process of VF vibration

- arytenoid cartilages rock inward to lightly adduct VF

- thoracic cavity is compressing for exhalation and subglottic pressure is increasing

- pressure pushes against the VF until pressure overcomes the VF resistance and they are forced open

- air flows through glottis (venturi effect)

- drop in transglottal pressure causes VF to pull inward toward each other (bernoulli effect)

How does viscoelasticity contribute to VF vibration?

the elastic resistance of the VF and the ease with which they return to their original shape and position

Mucosal wave

- wave like motion that travels laterally across the VF

- from the glottis to the sides of the laryngeal vestibule

Why do Mucosal waves occur?

occurs due to inferior margin adducting while superior margin is still abducting

Process of excitation of airflow

at VF closure, airflow is halted

- Supraglottal airflow continues upward, however there is a drop in pressure behind it due to VF closure

- Supraglottic airflow is sucked back down to VF

- There is a collision with the VF which causes the air molecules to vibrate (Newton’s third law) = excitation

- The rapid opening/closing of the VF causes shock waves of vibrating air up through the vocal tract

How do we modify frequency and intensity

???

Phonation threshold pressure

the minimal lung pressure required for phonation

How does phonation threshold pressure change for initiation versus sustaining?

beggining of phonation, having to overcome inerita, will require more pressure than end of phonation

momentum continues vibration, requiring less pressure

3 types of phonation onset

simultaneous / gentle / easy / soft onset

breathy / aspirate onset

glottal attack / hard onset

How is Simultaneous / gentle / easy / soft onset initiated?

by simultaneously exhaling and adducting VF at midline

How is Breathy / aspirate onset initiated?

by exhaling before adducting VF at midline

can be minimal or significant

How is glottal attack / hard onset initiated?

by adducting VF firmly at midline before exhaling

compression at midline and a build up of subglottic pressure with explosive release of air

3 categories of measurement for F0

levels of habitual use

levels of maximum performance

degree of regularity

Levels of habitual use

mean speaking F0 range depending on communication context

assessed via: sustained vowel production, reading passages, and spontaneous speaking task

Habitual pitch

the frequency range that we tend to speak in

Levels of maximum performance

lowest to highest frequency that an individual can produce

voices are capable of wider range than we habitually use

Degree of regularity

VF vibration is quasiperiodic

too much variability is abnormal

What is quasiperiodic?

not perfectly periodic

What are 2 ways we can measure variability (perturbation)?

Jitter and Shimmer

Jitter

nonvolitional variability in F0

short term perturbation (cycle-to-cycle)

measured via sustained vowel production

Shimmer

short-term variability in the amplitude of the acoustic waveform

measures via: sustained vowel production

We all have _____ & ______, but when it becomes too much, a voice disorder is occurring

Jitter, Simmer

Vocal range profile (VPR)

graph displaying the relationship between F0 and intensity

the wider the space between the lines, the more flexible the voice

How is VPR measured?

SLP plays a pitch which pt tries to match via sustained vowel production

First softly as possible then loudly as possible

How to measure lung pressure from intraoral pressure

small plastic tube which is placed in the mouth while producing /p/

the tube sends information to a transducer

Vocal efficiency

assesses the ratio of radiated acoustic power to aerodynamic power

Glottal efficiency

assesses the ratio of aerodynamic power to acoustic power at the level of the glottis

What decreases vocal efficiency?

incomplete glottal closure, resulting in increased airflow

s/z ratio

a maximum performance task used to assess the integrity of phonatory closure

ratio of maximum duration of /s/ to maximum duration of /z/

What is happening when /s/ is produced?

minimal resistance

VF abducted and open glottis

What is happening when /z/ is produced?

greater resistance

VF adducted and vibrating

Pros of s/z ratio?

easy to conduct & little set up

Drawbacks of s/z ratio?

difficulty establishing normative data

large amount of variability in voices

MPT ~ maximum phonation time

used to assess the integrity of phonatory glottal closure

vowel sound is maintained for as long as possible at a comfortable pitch and intensity level

Phonation quotient

a way to measure volume of air during sustained phonation

Visualization of VF vibration

photoglottography

electroglottography

high-speed imaging

videokymography

stroboscopy

Stroboscopy

most common for vizualization

uses a pulsing light to stimulate vibration at a slower rate

flashes at different points of the vibratory cycle and percieved as slow motion

microphone picks up F0 as bulb flashes at a rate slightly lower than F0

2 types of stroboscopy

rigid endoscope ~ through mouth

flexible endoscope ~ through nose

Vocal registers

a series of consecutive F0 values of approximately equivalent vocal quality

3 types of voice registers

modal, vocal/glottal fry, falsetto

Modal register

where majority of speech and singing takes place

Vocal/Glottal fry

CT is relaxed, very little VF tension

VF are short and thick with lax mucosal register

prolonged duration of closed phase