quiz 2 - Anatomy + Physiology of Phonation

2 categories of extrinsic larynx muscles

Elevators (supra hyoid) and depressors (infrahyoids)

intrinsic vs extrinsic laryngeal muscles

phonation vs elevation/depression of larynx, lengthening of vocal cords

digastric muscle

depresses mandible, elevates hyoid

Phonation (simple definition)

product of vibrating vocal folds in larynx

Mylohyoid

elevates hyoid bone and floor of mouth

Internal events of phonation

medial compression, longitudinal tension

Hyoglossus

depresses and retracts tongue

Genioglossus

main muscle of tongue - depresses and protrudes tongue

Frequency of vibration determined by

elasticity, stiffness, inertia

Medial compression

the degree of force that may be applied by the vocal folds at their point of contact

longitudinal tension

degree of stretching force of the vocal folds

periodic waveform

repeats itself in a predictable fashion

Higher medial compression

higher intensity

Higher longitudinal tension

higher pitch

Cycle

one point in a vibratory pattern to the same point again

Bernoulli effect

Pressure is lower where flow speed is greater.

Vocal folds vibrate as ____ passes through them

air

Prephonation

vocal folds move from an abducted to an adducted or partially adducted position via posterior cricoarytenoid

attack phase of phonation

lateral cricoarytenoid + interarytenoid muscles contract (brings folds together), thyrovocalis moves inward Pressure below the fold increases, causes folds to open.

Approximation phase of phonation

lateral +transverse oblique cricoarytenoids - pressure drops, velocity increases

3 types of phonation

Simultaneous, breathy, glottal Simul

Vocal registers

differences in modes of vibration for phonation

Modal phonation

phonatory pattern used during normal phonation

pressed modal phonation

medial compression is greatly increased

Stronger, louder phonation with a harsh or strident quality

breathy modal phonation

inadequate vocal fold approximation with excessive airflow between the vocal folds in the closed phase

position of vocal folds in whisper

adducted, tense

-why not a good thing to do when you're on vocal rest

falsetto phonation

very high frequency of VF vibrations, laryngeal muscles work to produce a very thin edge to the VF

glottal fry

when VFs vibrate very slowly and the vibration causes a slow, low pitch vocal burst making the voice sound crackly or creaky, airflow rate and air pressure that produces the VF vibration are both low and lung volume is less

Frequency

how often something occurs - cycles per second for sound

Hertz (Hz)

Cycles per second (how frequency is measured) - perceived as pitch

Fundamental frequency

rate of vocal fold vibration (Hz)

Pitch

a tone's experienced highness or lowness; depends on frequency

pitch increases as fundamental frequency

increases (and vice versa)

Optimal pitch

most efficient vibration for individual's vocal cords

Habitual pitch

basic tone that an individual uses most of the time

pitch range

the distance between the lowest and highest tones that a voice can produce

-can be increased w/ training, decreased w/issues

Change of pitch depends on...

tension, length and mass

Pitch increase comes from ___ vocal folds

tensing

cricothyroid

lengthens and tenses the vocal folds

posterior cricoarytenoid

anchors vocal folds

Pitch lowering

thickens and shortening of vocal folds via thyroarytenoid

Sound pressure level

measure of magnitude + acoustic signal

Decibels (dB)

perceived as loudness - ratio of two sound pressure levels

Intensity is measured in

decibels (dB)

Men tend other have lower voices because

longer/thicker vocal folds

Change of intensity

frequency dependent

-lateral cricoarytenoid + arytenoid cause forceful adduction of folds

suprasegmental aspects of speech

intonation, stress etc.

laryngectomy

surgical removal of the larynx - results in a tracheotomy

Muscle of abduction

(Abducted: Pretty Crocs !!)

posterior cricoarytenoid

muscles of adduction

("Lads can't?" Asked Thomas. "Oh, alright")

lateral cricoarytenoid, transverse arytenoid, oblique arytenoid

suprahyoid muscles (good morning, sand dunes!)

geniohyoid, mylohyoid, stylohyoid, digastric

Infrahyoid muscles (Save our Sauces Tiana!)

sternohyoid, omohyoid, sternothyroid, thyrohyoid

Phonation is sensitive to the ____ of the speaker

health

Pneumotachograph

airflow in a face mask

Fiberendoscopy

view the vocal folds from above via the nasal cavity- also measures swallowing

Subglottal pressure

pressure below the vocal folds - measured via hypodermic needle

Electroglottograph

electrodes on the neck- measures impedance which corresponds with vocal fold contact

Videostroboscopy

- Allows the human eye to see the vibratory motion of the VF in slow motion.

Source of fuel for phonoation

Respiration

Larynx located between cervical vertebrae _ and _

4, 6

Structural cartilage of the larynx (paired)

Arytenoid, Corniculate, Cuneiform

The hyoid bone is part of the larynx: true/false

False! (Articulates w/thyroid cartilage, but is only considered a meeting point)

Cricothyroid joint

allows from thyroid to rock forward to modulate pitch

when thyroid rocks forwards it creates a higher pitch

Cricoarytenoid joint

Junction between the cricoid and arytenoid cartilage.

Allows for rocking, gliding, and minimal rotation.

Allows for approximation

Larynx is a...

tube, made of cartilage w/valve-like adjustment at the top to keep things out if need be

Aditus

Entry to larynx

Supraglottal (above VF) cavity

Vestibule+ laryngeal ventricle

Vestibule

space between the aditus and the ventricular folds

Laryngeal Ventricle

space between true and false vocal folds

Laryngeal saccule

the anterior extension of the laryngeal ventricle; a pouch that secretes lubricating mucus into the laryngeal cavity

Glottis

Opening between vocal cords

-front 3/5 =membraneous

-back2/5=cartiloginous

Cricoid cartilage is...

unpaired

Layers of the vocal folds, Superficial--> deep

(See SLP I.D. Then Attend Visits)

Squamous Epithelium

Superficial Lamina Propria

Intermediate Lamina Propria

Deep Lamina Propria

Thyroarytenoid AKA Vocalis

hyothyroid membrane

sheet of membrane that suspends larynx from hyoid bone

Triticial cartilage

small nodule frequently embedded in lateral hyothyroid ligament

Hyoeppiglottic Ligament

cricotracheal ligament

connects lower border of cricoid cartilage with upper border of first tracheal ring

fibroelastic membrane

specialized membrane that connects the ends of the C-shape cartilage in the trachea; contains smooth muscle fibers

conus elasticus

from true vocal folds to the inferior border of the cricoid cartilage (upper part of fibroelastic membrane)

quadrangular membrane

lateral side of the epiglottis

all the way to the ventricular fold (lower part of fibroelastic membrane)

vestibular ligament

false vocal cord

Pairs of intrinsic laryngeal muscles

Tensors + Relaxers

Adductors + Abductors

Tensors

Cricothyroid, thyroarytenoid

Thyromuscularis

relaxes vocal folds

What causes a change in pitch

Stretching/tensing of vocal folds

Muscles responsible for pitch change

Thyroarytenoid, cricothyroid

Simultaneous attack

the vocal folds are adducted simultaneous with the initiation of expiratory flow

glottal attack

adduction of the vocal folds prior to the airflow- if hard may damage the vocal mechanism

Breathy attack

the vocal folds are adducted after the initiation of expiratory flow

Sustained phonation

vocal folds held in a fixed position by thyroarytenoid in the airstream - continued position bc of elasticity and inertia

Initiation of phonation

Pressure causes VF to adduct, vibrate in airflow

Three vocal registers

modal, glottal fry, falsetto