SLHS 566 Exam 2

What occurs during pressed voice?

• during pressed voice there is very strong tension of VFs (especially medial compression)

• this results in excessive approximation of the vocal folds

• Adduction period is longer

• Abduction is narrower

What occurs during breathy voice?

• Larger glottis aka abduction is wider

• VFs vibrate the same as they do in modal (normal) voice

  • since vibration is the same, they have to be adjusted somehow to increase airflow coming out

  • Adduction is basically non-existent — never fully close

    • weak medial compression

    • posterior gap never fully closes because the IA is not fully active

    • smaller degree of voicing effort

• Glottal area will not reach ‘0’

  • always present to a degree

What is the difference between breathy voice and a whisper?

A whisper is produced by maintaining the posterior glottal gap open but compressing the anterior portion of the vocal folds medially. This is unlike breathy voice where the entire glottis generally remains more open because of weaker medial compression. During a whisper, air is only able to come through the posterior glottal gap which requires more voicing effort. The vocal folds are also not vibrating during a whisper, however they do vibrate in breathy voice.

Although perceptually, there is no clear boundary between a whisper and breathy voice.

What are two types of sound that can be produced without vocal fold vibration?

• glottal stop

• glottal fricative

How is a glottal stop produced?

• a glottal stop is produced through a complete obstruction of airflow which causes tracheal air pressure build up (pressurization phase)

• this airflow is then let out by VF abduction— this instant release of that tracheal air pressure and airflow results in a noise burst (release phase)

• for a glottal stop to be produced the glottis has to be completely obstructed

  • cannot build pressure if there is a gap

How is a glottal fricative produced?

• unlike a glottal stop, to produce a glottal fricative, the glottis will not be completely adducted

  • a very tiny glottal gap will remain where the air will need to get through

• Airflow will travel through a constructed airway (glottis) which results in turbulence noise

  • This narrow opening turns smooth airflow into turbulent airflow (chaotic, irregular air particle movement), which creates a continuous hissing or buzzing noise known as frication

What theory explains why vocal folds vibrate?

myoelastic-aerodynamic theory

What is the myoelastic-aerodynamic theory?

The myoelastic-aerodynamic theory of phonation (MEAD) states thatvoice production results from an interaction between muscle action, tissue elasticity, and lung airflow

Different components:

• Myoelastic (Muscle & Elasticity): Laryngeal muscles bring the vocal folds together (adduction) and set their tension and mass. The elastic properties of the tissue allow the folds to snap back to the midline after being forced apart.

• Aerodynamic (Airflow & Pressure): Air pressure from the lungs (subglottal pressure) builds up beneath the closed folds until it blows them apart. As air rushes through the opening (the glottis), aerodynamic forces and tissue recoil assist in closing the folds

  • the bernoulli effect is part of the aerodynamic component of vocal fold vibration

What is the bernoulli effect? How is it unfortunately involved in phontion? :(

• Generally, the bernoulli effect states:

  • The faster the air molecules move, the lower the air pressure

  • The slower the air molecules move, the higher the air pressure

• How it is involved in phonation:

  • Air Pressure Build-Up: Laryngeal muscles bring the vocal folds together at the midline (adduction). Air pressure from the lungs (subglottal pressure) builds up beneath them until it forces the vocal folds apart.

  • Acceleration and Pressure Drop: As air rushes through the narrow opening between the folds (the glottis), the velocity of the airflow increases. According to Bernoulli's principle, an increase in fluid velocity causes a localized drop in static (lateral) pressure against the vocal fold walls.

  • The Suction and Closure Phase: This drop in pressure creates a suction force that pulls the medial surfaces of the vocal folds back toward each other.

  • Self-Sustaining Vibration: Combined with the natural elasticity and recoil of the vocal fold tissue, this alternating cycle of pressure build-up and Bernoulli suction repeats hundreds of times per second, chopping the airflow into rapid acoustic pulses that create voiced sound.

Why wouldn’t out motor system be able to be soley responsible for phonation?

our vocal folds are moving hundreds of times per second. that requires intense and frequent neuronal firing. Our motor system is not equipped to support phonation on its own but it plays an important role in putting all our systems in place so that once PTP is reached the vocal folds become a self-sustaining system.

Describe the process of a vibratory cycle

1. tracheal air pressure builds up

2. vocal folds separate bottom up

3. glottis appears, pressure releases, vocal folds move laterally

4. full lateral excursion of vocal folds

5. vocal folds move toward midline

6. vocal folds approximate from bottom up

7. cycle complete and renews

Describe why the one mass model is not a true representation of vocal fold vibration?

• only models translational movement and not rotational movement

• the vocal folds do not function as one big mass which is what this model proposes

Describe why the two mass model is not a true representation of vocal fold vibration?

it fails to adequately represent the distinct anatomical layers of real human vocal tissue

• the two masses represent upper and lower sections of the fold, but the arrangement acts primarily as a "cover" model. It does not allow for independent, coupled oscillation between a flexible outer mucosa ("cover") and a deeper muscle core ("body")

Describe why the three mass model is the best model of self-sustained VF vibration?

• It uses two small upper/lower masses to represent the flexible mucosal cover (epithelium and lamina propria) and one large mass to represent the underlying thyroarytenoid (body) muscle, connected by springs and dampers

• shows both rotation and translation

Where does the push come from that sets the vocal folds off into motion?

• Intraglottal pressure P_g

  • pressure within the glottis

  • the air pressure exerted directly within the space between the vocal folds—is the primary driving forcethat initiates and sustains vocal fold vibration and voice production

Explain the vocal fold mechanics that cause our vocal folds to open and close. The response to this question is probably longer than my wedding vows will be ngl.

REMEMBER: OUR VF OPEN FROM BOTTOM TO TOP!

1. Intraglottal pressure (Pg) pushes VF outward (apart)

2. Since we open from bottom to top, the lower portion leads the upper one (a1>a2)

3. Glottis takes convergent shape

   1. occurs when the inferior (bottom) margins of the vocal folds are farther apart than their superior (top) margins as air passes through them — occurs during open phase

   2. in a convergent-shaped glottis, the average intraglottal pressure Pg closely correlates with and is nearly equal to the subglottal pressure Ps

4. Increase in restoring force due to vocal fold elasticity

   1. the more you push vocal folds at the bottom apart the more the restoring force pushes against it

   2. the restoring force is fighting against the air that deformed the VF

   3. force of air on the VF vs force of the VF themselves

   4. this restoring force is initially greater for the lower portion because the VF have been displaced more than the top portion has

5. Widening of the glottis decreases intraglottal pressure Pg

   1. Increasing space decreases pressure — wider the glottis the lower the Pg will be

   2. At the same time, restoring force continues to increase because VF are further from the midline

   REMEMBER: OUR VF CLOSE BOTTOM TO TOP!

6. Change direction of motion

   1. due to: decreasing Pg and increasing restoring force

      1. Pg is typically enough to overcome restoring force but once the glottis gets too wide pressure decreases and restoring force becomes greater than Pg

      2. RF > Pg = Closing of the lower portion

7. Lower portion becomes divergent

   1. occurs when the superior (upper) margins of the vocal folds are wider apart than the inferior (lower) margins — occurs during closing phase of vibration

   2. lower portion is very close to closing during this phase

   3. the intraglottal pressure (Pg) and supraglottal pressure (Pi) become very close

8. All of the above occur with the top portion too, leading to top closure and then rinse repeat!

What is the Phonation threshold pressure?

the minimum subglottal pressure at which VFs sustain vibration

• aka the least amount of air beneath the VF to set it all in motion so it can vibrate

For vocal efficiency, what level of PTP is desirable?

• low PTP is desirable

  • easier, more efficient, no trauma

What kind of things affect PTP?

• size of our vocal folds

  • big, thick = lots of mass to move

• any lesions, swelling, etc..

  • increases mass

• VF histology

  • as you get older elasticity decreases so PTP becomes higher

• hydration

  • dry VF = sticky and require more PTP

• Vocal fatigue

• Pitch

  • high pitch causes PTP to be higher because things are much more stiff

  • Low pitch doesn’t require a high PTP because things are much looser

what is the f0?

the frequency we are speaking with

• fundamental frequency of our voice

• how often do our vocal folds vibrate (complete a full glottal cycle) per second

• f=1/T

• Measured in Hz

• 
  

What is the perceptual correlate of f0?

pitch!

f0 is the acoustic measure

What does a change in f0 mean?

a change in the f0 means there is a change in how often our VF vibrate

If frequency/pitch increases that means our vocal folds are vibrating faster

• glottal area closes more often and is closed for less time

If frequency/pitch decreases that means our vocal folds are vibrating slower

• glottal are takes longer to close but is closed for more time

Why do we need to change our f0?

• pitch change can provide meaning

  • questions

• pragmatic purposes

• some languages, such as tonal languages, rely on changes in pitch to convey meaning

What two factors determine the f0?

Driving forces of pitch!

1. Mass (m): Fixed —> regardless of f0 mass/weigh of VF stays the same barring any effects from a disorder

2. Stiffness (k): main driver, dynamic

How are stiffness and mass related to pitch?

direct relationship

increase in stiffness = higher pitch

decrease in stiffness = lower pitch

inverse relationship

higher in mass = lower pitch

lower in mass = higher pitch

Formula

k/m = fo

What controls the f0?

Key drivers of f0!

1. thyroaryetnoid

   1. TA shortens VF

2. cricothyroid: contraction of CT causes thyroid and cricoid to rotate which causes the vocal folds to change in length

   1. CT lengthens VFs

Stress (tension) in the vocal folds has a passive and an active component. What are they?

Passive component - we have no control over this

• mucosa

• ligament

  • strain is the only way to change these layers → we cannot directly affect these layers of the VF → BUT we can do it indirectly → contracting the TA muscle strains these layers

Active component — we have control over these things

• muscle contraction

What happens if we have full activation of the CT?

• VF length increases

• high tension in cover and body (passive)

• high f0

What happens if we have full activation of the TA?

• VF length decreases → the TA is the VF so if it contracts it will shorten

• low tension in cover → lThe cover contains no muscle fibers—it is purely mucosa, collagen, and elastin. It cannot contract on its own. Its stiffness is entirely dependent on how tightly it is stretched from end to end but since the VFs are shortened the cover is loose

• high tension in body (muscle) → becomes very tense + stiff because it is contracting

• f0 could be both high or low because of the high tension and the short/loose aspect

What are the possible f0 effects of other laryngeal muscles?

LCA: medial compression can lead to higher pitch

• adducts

• When it fully full force contracts, anterior medial compression is very high → they are absolutely squeezed together that they almost become one and cant vibrate → takes out mass which increases picth

PCA: bracing effect, affects stiffness, and increases picth

• moves arytenoids posteriorly which pulls the VFs a bit and lengthens them

How can breathing impact f0?

increase in subglottal pressure will increase pitch

• the greater the subglottal pressure you build up the faster the vibration will be (like a windmill)

What does CT and TA activation look like when the VF are short?

• high TA activation

• low CT activation

What does CT and TA activation look like when the VF are long?

• low TA activation

• high CT activation

Explain what the attached graph is showing.

This graph is showing the results of different activation levels

• we can achieve the same pitch through different combinations of activation levels aka there is no one way to produce a particular pitch

• it is a highly complicated interplay that requires precise coordination between the muscles to obtain a particular pitch but they can be coordinated in more than one way to obtain that pitch!

How do age differences and differences in laryngeal structure impact f0?

• mass changes as we age!

  • After puberty mass is mainly fixed for the person so thats why it is not the main driving force (stiffness is)

  • BUT between populations mass differs

• pitch decreases as we age

How does the infant oral cavity, pharynx, and larynx differ from that of an adult?

• larynx and pharynx are located more superiorly and anteriorly in infants

• larynx is not on a perpendicular axis — titled forward in infants

• epiglottis is floppy in infants

• larynx is very compressed so membranes are very small and not very visible

• tiny VF in infant

• huge arytenoids in infant

• pharynx is small

• the tongue is massive and occupies most of the oral cavity

• no teeth

• no space between velum + epiglottis

  • prevents choking while feeding

  • creates a seal/blockage in the back of the pharynx

At what age are VF finally fixed in mass and length?

At age 20

from puberty to 20 years old our length is still changing

• males have longer VF, larger laryngeal cartilages, and greater VF thickness than women

• infants VF vibrate faster bc of mass difference → lighter than adult VFs

Label the following graphs with their corresponding population. Discuss what you see depicted across graphs.

G1: Male

G2: Female

G3: Child (4yo)

• pitch numbers are different across all three graphs

  • BUT all curves are similar because it all functions in the same way throughout life

• the anatomical differences in the larynx across population account for drastic pitch representations in these graphs

What are some age-related effects that impact f0 control?

Age related effects

• degeneration of cartilage and soft tissue

  • ossification: our cartilages become more bone like, loose flexibility and become more stiff

  • calcification: cartilages become more brittle and start to flake and chip

• Alters structure and vibratory characteristics of VFs

  • muscle atrophy: muscles may become weaker

  • nerve fiber loss: TA is less innervated

  • layers may become very thick and more collagenous and others may just degenerate

• May relate more to physiologic age not chronological age

What kind of consequences do those age-related effects have on f0 and vocal quality?

• incomplete glottal closure → affects vocal quality leading to a breathy aspect

• alternations in mucosal wave → change in how VF vibrate because layers change in composition

  • scars or trauma may lead to a harsh and strained vocal quality

• reduced vibration → getting into a particular f0 more difficult

  • more effortful vocal quality

• possible tremor → shaky voice

• breathier voices, greater f0 variability

How do we control intensity? Three steps!

• increased lung pressure (respiratory drive) → adjusting our breathing apparatus

  • sounds are pressure fluctuations → more pressure fluctuations = increase in intensity

  • Higher subglottal pressure

  • greater amplitude of VF vibration/flow

    • VF open more than usual causing an increase in flow because more air can come out

• highly adducted VFs

  • produce sharper cutoff of glottal flow

  • if we have half-assed VF closure air will escape and pressure won’t build as high as it can

    • it would also not provide much resistance to subglottal pressure

• configuration of vocal tract

  • OPEN WIDE!

This image shows the voice range profile. What does the green represent?

speak as quiet as you can in the lowest pitch you can

This image shows the voice range profile. What does the purple represent?

speak as loud as you can in the lowest picth you can

This image shows the voice range profile. What does the blue represent?

speak as loud as you can in the highest pitch you can

This image shows the voice range profile. What does the pink represent?

speak as quiet as you can at the highest pitch you can

This image shows the voice range profile. What does the yellow represent?

voice area

the purple and blue provide the upper boundary of vocal range

the green and pink provide the lower boundary of vocal range

• if in the low area, that represents low pitch → vocal folds will be short and loose

  • can’t be loud is you have wobbly and loose VF

  • why its hard to be loud at low frequencies

When is glottal flow at 0? When is glottal flow have a value?

• when VF are closed glottal flow is at 0

• when VF are open air is flowing through and there is a unit of glottal flow

What is the open quotient?

The open quotient is the ratio of then open phase of the glottal waveform to the total period. AKA relation of open phase of the glottis to the full glottal cycle.

• open phase time/total time of glottal cycle = the % of the full glottal cycle in which the glottis os open

  • (T4-T2)/(T4-T1) = open quotient

• The longer the VF are together → lower the open quotient (Q0) will be

• The longer the VF are apart → the bigger the open quotient (Q0) will be → voice may start to sound breathy is really high

Range for the quotient: most extreme case: 1 (probs wont reach this tho bc of adduction) → minimum: 0 (prob won’t happen either)

What is the skewing quotient?

The skewing quotient applies only to the open phase of the glottal waveform and is the ratio of the “rise time” to the fall “fall time”

• rise time (when flow is rising/increasing) / fall time (when flow is falling/decreasing) = skewing Quotient

  • (T3-T2)/(T4-T3)

• When glottis is closing its still open but less and less air is coming through

• if Qs id higher you speak louder → cutting off more quickly allows for greater subglottal pressure → rise time > fall time

  • if Qs is 1 this indicates rise time = fall time (symmetrical)

Where does air movement originate?

Air movement originates in the lungs/diaphragm

• when lungs expand > air comes in

• when lungs volume is reduced > air goes out

  • this is an autonomic response → medulla controls it

  • breathing is conditioned by chemoreceptors that detect CO2 in the body when it detects increased CO2 it moves to bring o2 back in

What is Boyle’s law?

volume of a gas is inversely proportional to its pressure (in a closed system)

• volume (space air fills) of a gas is opposite to the pressure in a system where not much is happening

• if volume increases, pressure decreases

• if volume decreases, pressure increases

• Pv=nRT

What is equalization of pressure?

air flows from high pressure areas to low pressure areas

Explain how air comes in and out of the system using boyle’s law and equalization of pressure.

Boyle's Law and the equalization of pressure help explain inhalation and exhalation. Boyle's law states that when volume is high, pressure is low or when volume is low, pressure is high. Equalization of pressure states that air likes to flow from high pressure areas to low pressure areas.

When we put these two principles together we can see that air from the environment is going to want to travel into our respiratory system when our lung volume is high (the diaphragm contracts). This describes inhalation. When our lung volume decreases (the diaphragm returns to its natural state) the pressure in our lungs will increase which is going to make the air want to rush out of our respiratory system and back out into the environment. This describes exhalation. 

• volume expands first via muscles

What are the three types of pressure associated with our respiratory system?

• alveolar pressure

  • inside lungs (air pressure)

• pleural pressure

  • inside thorax but outside lungs

• abdominal pressure

  • inside abdominal cavity

What are the passive forces in respiration?

• passive forces

  • inherent + always present

  • natural recoil

    • of ribs → ribs are elastic when we breathe in they are out of position and want to go back so their recoil

  • surface tension on the alveoli

    • alveoli are at the bottom of the lungs

    • if you blow in air these sacs also grow

  • gravity

    • pulls everything down

    • force on the diaphragm → goes down

    • affects breathing but we can’t do anything about it

What are the active forces in respiration?

• willfully applied by skeletal muscle (esp. chest muscles)

  • depends on the amount of air inside the apparatus

What are alveoli?

tiny, hollow, cup-shaped air sacs at the very end of the respiratory tree in the lungs where the body exchanges oxygen and carbon dioxide.

• 300-500 million

What happens when the sternocleidomastoid contracts?

expands thoracic cavity by elevating the sternum + clavicles which elevates the ribs

• inhalation

origin: sternum + clavicle

insertion: mastoid process

What happens when the pectoralis minor contracts?

• it elevates the ribs

• inhalation

origin: rib 2-5 (near their cartilage)

insertion: scapula (front surface)

What happens when the pectoralis major contracts?

• allows us to expand our chest cavity outward by pulling ribs and sternum outside (upward)

origin: sternum + costal cartilage

insertion: humerus

What happens when the external intercostals contract?

• inhalation

• moves rib cage up as a unit → expands the thoracic cavity

• stiffens space between the ribs → maintains form + shape which prevents collapse and immediate recoil

11 muscles filling outer space between ribs (= rib interspaced)

orientation: forward + down ward (how you put your hands in your pocket)

What happens when the internal intercostals contract?

• exhalation

• moves ribcage downward as a unit and stiffens space between ribs

11 muscles filling inner space between ribs (underneath the external ones)

What is the diaphragm? When happens when it contracts?

• dome-shaped structure

• unpaired muscle

• has a central tendon + sheet of muscle tissue

  • tendon is stiff and inelastic

• muscle fibers project upward into central tendon

• contraction of this muscle causes it to flatten by pulling it down

It is the sole driver of increasing volume of lungs by lowering and allowing for lung expansion

List the abdominal muscles.

1. rectus abdominis

2. transverse abdominis

3. obliques

   1. internal

   2. external

What happens when the rectus abdominis contracts?

Rectus abdominis

• compartmentalized muscle

  • a group of muscles, nerves, and blood vessels enclosed together in the body by a tough, inelastic layer of connective tissue

• Contraction

  • muscle of expiration → squeezes air out

    • lowers ribs and sternum

    • forces front abdominal wall inward

Origin: front edge of coxal (hip) bones

Insertion: sternum and 5-7th costal cartilages

What happens when the transverse abdominis contracts?

Contraction:

• muscle of expiration

• brings the front and side of the abdominal wall inward

Origin: upper surface of coxal (hip) bones and costal cartilages (inner surface)

Insertion: abdominal aponeurosis

What is the abdominal aponeurosis?

An aponeurosis is a thin sheath of connective tissue that helps connect your muscles to your bones. Aponeuroses are similar to tendons.

The abdominal aponeurosis helps connect our abdominal muscles to bones.

• broad, flat sheet of dense, fibrous connective tissue that covers, shapes, and connects the muscles of the abdominal wall.

What happens the obliques contract?

contraction:

• both externals and internals pull the lower ribs downward and forces the front abdominal wall inward

What are the two divisions of the breathing apparatus?

1. Pulmonary apparatus

2. chest wall

What structure divides the two divisions of the breathing apparatus?

the diaphragm

What are the components involved in our pulmonary apparatus?

• pulmonary airways

  • Upper airway: nasal cavity to larynx

  • Lower airway: trachea, bronchi, bronchioles, alveolar ducts, alveolar sacs, and alveoli

• lungs (5 lobes)

What are the three functions of the pulmonary apparatus?

• air containing

• air conducting

• gas exchanging

How many lobes does the right lung have? What about the left lung?

Right lung

• 3 lobes

Left lung

• 2 lobes

Alveoli surface area

An adult human has about 300-500 million alveoli across both lungs, creating a massive surface area of roughly 70 to 85 square meters (similar to a tennis court) for gas exchange

The greater the surface area the greater the gas exchange!

Alveoli gas exchange process

• Inhalation: When you breathe in, air travels down your windpipe and into the alveoli, filling them like tiny balloons.

• Gas Exchange: Oxygen passes through the ultra-thin alveolar walls into surrounding blood vessels (capillaries).

• Exhalation: At the same time, carbon dioxide moves from the blood into the alveoli so you can breathe it out.

What four parts make up the chest wall?

• rib cage wall → bones around thoracic cavity

• diaphragm → dome shaped muscle that is the main muscle for breathing

• abdominal wall → ab muscles that encircle our abdominal cavity

• abdominal content → organs

Which of the four components of the chest wall are involved in breathing?

• rib cage wall

• diaphragm

• abdominal wall

What are the two types of rib cage movement?

• pump handle motion

• bucket handle motion

Describe the pump handle motion of the ribs

Thepump-handle movement refers to the upward and forward rotation of the upper ribs and sternum during inhalation, which increases the front-to-back (anteroposterior) diameter of the chest cavity

• During exhalation it moves the ribs downward and backward decreasing the diameter of the chest cavity

Describe the bucket handle motion of the ribs

The bucket-handle movement is a respiratory motion of the lower ribs that increases the side-to-side (transverse) diameter of the thoracic cavity during inhalation

• during exhalation it moves the ribs downward and inward to decreasethe side-to-side (transverse) diameter of the thoracic cavity

How does the diaphragm change shape during inhalation vs exhalation?

inhalation

• flattens

exhalation

• becomes more domed

How does the abdominal wall move for breathing?

most movement occurs alond the anterior and posterior dimension → squeezes the cavity to expel air

How does body position, body type, age, and sex influence breathing?

Body position:

• Moving from a seated or upright position to a supine or inclined position reduces tidal volume

• In an upright or seated posture, the rib cage contributes more to chest wall motion. When lying supine, the percentage contribution of the abdomen to tidal volume increases significantly.

Body type

• High body mass or increased abdominal fat places physical upward pressure on the diaphragm, decreasing functional residual capacity and total lung capacity.

Age

• As people age, the chest wall and rib cage cartilage tend to stiffen, reducing the overall contribution of the rib cage to tidal volume

Sex

• On average, biological females have smaller overall lung dimensions and smaller rib cage compartments compared to biological males, even when adjusted for height. This results in smaller absolute lung volumes and lower maximal expiratory flows in women.

What is tidal breathing?

relax breathing in which the time to breathe in is about the same time as the time to breathe out.

• when breathing out you just relax and natural recoil of ribs goes back → don’t need much muscle involvement

What is the composition of inhalation / exhalation of speech breathing?

Inhalation: 10% → quick breath in

Exhalation: 90% → long exhalation during speech

• allows us to speak for a long time

• muscles help lungs deflate in a constant steady rate

What is the target of speech breathing?

• maintain constant alveolar pressure

  • requires coordination of inspiratory and expiratory muscles

    • As you speak and exhale, your lung volume continuously shrinks. Naturally, the elastic recoil of the lungs drops as volume decreases. To keep alveolar pressure steady despite this drop in natural recoil, your respiratory muscles (such as the abdominal and internal intercostal muscles) must constantly adjust their muscular effort to "take over" and maintain the driving pressure

    • that is why speech breathing is much more effortful than tidal breathing

Why do we need alveolar to remain constant during speech breathing?

We need constant alveolar pressure during speech breathing to maintain a steady vocal intensity (loudness) and a stable pitch while speaking

How do lung volume, rib cage wall volume, and abdominal wall volume change during speech breathing? What about alveolar pressure?

• lung volume, rib cage wall volume, abdominal wall volume all decrease as we breathe out and speak

• alveolar pressure does not change during speech breathing. It remains constant!

What is lung volume?

amount of air in the lungs at a given time

What is lung capacity?

a combination of various lung volumes

What are the four types of lung volume?

1. tidal volume

2. inspiratory reserve volume

3. expiratory reserve volume

4. residual volume

What is tidal volume?

volume inhaled and exhaled during a cycle of respiration

• ~ ½ L of air

What is inspiratory reserve volume?

volume of air that can be inhaled above TV

• can breathe in a lot more till your lungs are fully full → not a regular process

What is expiratory reserve volume?

volume of air that can be exhaled below TV

• same as IRV but breathing out → squeeze out everything → abdominal muscles come in to squeeze the abdominal cavity which decreases thoracic cavity

What is residual volume?

volume of air remaining after max expiration; cannot be expelled voluntarily

• we cannot squeeze everything out → if we did our lungs would collapse and stick together → takes a lot of energy to force breathing when lungs are in this state.

• death breath

  • you breathe it out and its lights out

What are the four types of lung capacity?

1. vital capacity

2. functional residual capacity (FRC)

3. total lung capacity (TLC)

4. Inspiratory capacity (IC)

What is vital capacity?

volume of air that can be exhaled after max. inhalation

• IRV + TV + ERV = VC

• all of the air that is important and that we have access to

What is the functional residual capacity (FRC)?

volume remaining as end-expiratory level

• aka all the air that is left after tidal breath

• ERV + RV

What is total lung capacity (TLC)?

total amount of air your lungs can hold (TV + IRV + ERV + RV)

• all volumes together

What is inspiratory capacity (IC)?

max. of air that can be inspired from end-expiratory level (TV + IRV)

• the moment you stop breathing out you can start breathing in → the air that comes in after exhalation (biggest deep breath) is your IC

• the max inhaled air the lungs can hold