phonation tones and nerves

nerve that innervates all intrinsic laryngeal muscles

vagus

what does damage to the vagus nerve do

destoys ability to phonate properly

suprahyoid extrinsic muscles are innervated by

facial, hypoglassal, trigeminal nerves

infrahyoid extrinsic muscles innervated by

hypoglossal nerve

larynx is divided by cartilages and muscles into 3 cavities

supreglottic, glottic, and subglottic

cavity formed by epiglottis and vestibular and ventricular folds

supraglottic (above VF)

cavity formed by VFs and glottis

glottic

cavity that is space below the VFs but above trachea that contains mucous and hairs designed to remove debris

subglottis

the vocal folds 5 tissue layers

squamous epithelium, superficial lamina propina, intermediate lamina propina, deep lamina propina, muscles

the mucousa lining contains the first two tissue layers of the vocal folds

squamous epithelium, superficial lamina propina

the vocal ligament contains tissue layers 3 and 4 of the vocal folds

intermediate and deep lamina propina

2 parameters the vocal folds manipulate

pitch and amplitude

frequency of vibration measured in Hz

pitch

loudness of vibration measured in dB

amplitude

in speech higher loudness (amplitude) → higher —

pitch

pitch of the voice: our perception of the — of phonation represented by f0, the number of cycles per second the VF produce

fundamental frequency

more vibrations per second = higher/lower f0

higher

pitch is modified entirely by the

VFs

frequency at which we typically speak

habitual pitch

— more — vocal folds vibrate more quickly

thinner, tense

higher pitch is created by — muscles pulling thyroid cartilage down on its hinge and causes distance between arytenoids and thyroid to increase, stretching the VFs making them thinner and tenser

cricothyroid

pitch is lowered by the — muscle contracting causing thyroid to move back (arytenoids always stay in place) makes this muscle bunch up and the VF are thicker and more flaccid, move more slowly and pitch is lowered

thyroarytenoid

highest pitch (falsetto) maxxes out the function of the — muscles and must then use the extrinsic — to help lift entire larynx and stretch conus elasticus

intrinsic, suprahyoid

part of the conus elasticus so that extra tension is added to the VFs

vocalis ligament

— maxes out intrinsic muscles in opposite direction, the infrahyoid muscles are engaged to pull larynx down, tension on conus elasticus is decreased and tension on vocalis ligament is reduced

vocal/glottal fry

intensity (loudness) of phonation is determined by —— built up during exhalation

subglottal pressure

most humans have intensity range

0-70dB

why does higher pitch increase with higher intensity?

higher subglottal pressure requires tightenting of VFs, tense things vibrate faster

the — model si a theory of how the VFs vibrate

myoelastic aerodynamic

the myoelastic aerodynamic model relies on muscle elasticty and behavior of —

airflow

fluids and gases travel faster as their space is constrained is the

bernoulli principle

how phonation happens:

1. subglottal pressure builds up below VF until VFs open

2. air rushes from subglottal to supraglottal (air high→low pressure)

3. VFs try to close gap again but this only increases rate of airflow (bernoulli)

4. causes vacuum to be drawn in cavities, brings VFs back together

5. repeat 100x per second

two phonatory phases

pre-phonation phase, attack phase

during this phase VFs move from abducted to almost adducted state, cuts off most airflow and subglottal pressure builds, bernoulli effect then adducts folds completely

pre-phonation

during this phase of phonation is the period where VFs undergo regular vibration, VFs adducted, when subglottal pressure is high enough, Vfs adduct and burst of compressed air is released, bernoulli sucks them back toher and return folds to non-deformed position

atack phase

you can phonate in 3 different ways:

simultaneous vocal attack, breathy vocal attack, glottal attack

co-ordinate adduction and expiration onset, so they begin simultaneously

simultaneous vocal attack

significant airflow before VF adduction, when unvoiced sound begins an utterance or if something obstructs VF adduction

breathy vocal attack

adduction prior to airflow like a cough, start of utternaces with stressed vowel

glottal attack