Physiology of Phonation - A&P

what is voicing

adducting the vocal folds together so that they vibrate during the production of vowels and voiced consonants

what is voiceless

abducting the vocal folds during the production of voiceless

consonants.

what is intonation

changing vocal fold vibration rate changes the perceived pitch

of the speaker’s voice (higher rate = higher pitch)

example of falling intonation

“Gracie did not go to school”.

example of rising intonation

“Gracie did not go to school?”

what does this show

adduction of vocal folds

what does this show

abduction of the vocal cords

what does this show

stretching the vocal cords

thyrovocalis is a ____

tensor

thyromuscularis is a ____

relaxer

what are the movements of laryngeal housing by extrinsic muscles

upward/downward and forward/ backward

glottal size when abduction happens

larger

glottal size when adduction happens

smaller (closed)

what is the effect of mass on the rate of vocal fold vibration

increasing mass decreases the rate of vibration

stiffness of the vocal cords varies by ________

location of the fold

stiffness is the opposite of _____

compliance

how are /p/, /t/, /k/ (transient sounds) generated

1. pressurization phase → release phase

2. glottal configuration change (add-abd) – burst of transient airflow that vibrates supralaryngeal structures

3. glottal configuration change (add-abd)

how is /h/ (sustained utterance) generated

glottal configuration adjustment → turbulent airflow

how is sound generation for voice (sustained) produced

1. sustained airflow (VF opening/closing)

2. gottal configuration: adduction (posturing)

“myo”+”elastic”=

properties of the muscles and tissues

what does aerodynamic mean for opening and closing

opening: positive pressure

closing: bernoulli effect and elasticity

what is the bernoulli effect

as speed increases, pressure decreases, velocity increases

what happens during the myoelastic aerodynamic

1)Vocal folds are appropriately positioned (postured)

2) Subglottal pressure is built up below the folds

3) folds repeatedly open and close because of repeated pressure build-up, drop, etc.

why dont the vocal folds open/ close during phonation

because there is a separate muscle contraction for each opening/closing

movement

under what circumstances do the vocal folds open / close automatically

as long as the folds are in the appropriate positions, and there is sufficient buildup of pressure below them

what is the vocal fold opening and closure like

a wave

what 3 phases are manipulated by subglottal pressure

1. opening

2. closing

3. closed

open posterior → open anterior → close anterior → close posterior

what does fundamental frequency (pitch) reflect

reflects the vibratory rate of the vocal folds. (how many vibrations (open and close) during one sec)

what is intensity

loudness, power from respiratory system, shape of glottis, shape of vocal tract, lip opening

how do we regulate our voice

pitch, intensity, quality

aperiodic sounds are ____ in normal voice production

noisy

periodic sounds are _____ in normal voice production

intense, clear, and involve resonance

in normal voice production, vocal fold abduction is what type of sound

aperiodic

the higher rate of vibration, the _______ the f0, which we percieve as ____ pitch

higher; higher

vocal fold vibration create cyclical waveforms and it’s rate is defined as

cycles/second (Hz)

extremely slow vocal fold vibration is about 60 vibrations per second and produces a ____ pitch.

low

extremely fast vocal fold vibration approaches 2000 vibrations per second and produces a very ___ pitch.

high

men's vocal folds typically vibrate from ___ to __ Hz, mean = 115 Hz

90 to 500

women's vocal folds typically vibrate from __ to __ Hz, mean = 200 Hz.

150 to 1000

is VF tension major determinant of rate of VF vibration true or false

true

is distribution of the VF mass is related to length + mass

no, its length + tension

increased mass = _____

decreased vibration

increased length = ______

decreased vibration

females VF are longer true or false

false, mens are longer

by changing the volume of airflow…

you increase in subglottal pressure

what are vocal registers

we can alter the quality of our voice by making a variety of other changes to the relative position of our vocal folds or their tension

what is glottal fry

lowest f0, VFs close quickly, long closed phase of the cycle

free margins of VFs appear _____ but are tightly ____

flaccid; closed

bubbles of air escaping in glottal fry gives what kind of quality

popcorn

glottal fry is least flexible and has low airflow true or false

true , frequency < 100

what is modal register

widest range of f0, normal speaking voice

what are pressed vocal registers

louder modal phonation where VFs are strongly medially compressed

what are breathy vocal registers

significant gap left between the vocal folds as they vibrate, resulting in excessive airflow

what is falsetto

highest f0, VFs don’t close completely

loudness control is determined by

glottal resistance

objective parameters in vocal quality

• all acoustic parameters

  • f0

  • intensity

  • jitter

  • shimmer

  • spectrum

• open quotient

• speed quotient

subjective parameters in vocal quality

• hoarse

• rough

• strained

• strangled

• breathy

• male vs female

what is this

spectrogram

how can we see the vocal cords

laryngoscopy (endoscopy+larynx), shows the interior larynx

what are the two types of laryngoscopy

direct and indirect

what does this show

direct laryngoscopy (under anesthesia)

how was old-school laryngoscopy performed

dental mirror pushed to the soft palate

why is old school laryngoscopy not ideal

only larynx structures could be seen

what does this show and how is it conducted

a recording of the larynx, camera fastened to laryngeal mirror

modern methods to see the larynx and what are they like

• endoscopy - flexible and rigid, visualizes tissue, nasal

• videostroboscopy - allows human eye to see vibratory motion of VF in slow motion

what is this

endoscopy

what happens if there is reduced respiratory drive (hypoventilation)

breathing muscles weaken and breaths become too slow or shallow.

what happens if respiratory airflow is redirected

significant disruption to normal breathing which physiology results in inefficient gas exchange, increased respiratory effort, and a high risk of respiratory distress or failure.

what happens to lesions, aging, and intubation when you increase the mass of the vocal folds

due to lesions; causes lower pitch, persistent gaps and excess air escapes, decreases vibration and increases stiffness

what happens if you conduct a total laryngectomy

breathing occurs through a permanent opening in the neck (stoma), the ability to speak using vocal cords is lost, and the mechanism for swallowing is altered

what happens if you were to paralyze the intrinsic muscle

disrupts the essential functions of breathing, speaking, and swallowing

what is this used for

laryngectomy

what happens to lesions, aging, and intubation when you decrease the mass of the vocal folds

due to aging; breathy, weak, trembly voice, thinning that leads to curving which prevents the folds from meeting properly, loss of atrophy and thins tissue layers