Phonatory Recap

The larynx is a cartilaginous tube that connects inferiorly to the respiratory system (the trachea & lungs), and superiorly to the vocal tract and oral cavity

• the pulmonary power supply
• the laryngeal valve
• supraglottic vocal tract resonator

the intrinsic component of the resp system which functions as a protective device for the lower resp tract

1)Prevents air from escaping the lungs 

2)Prevents foreign substances from entering the larynx

3)Forcefully expels foreign substances which threaten to enter either the larynx or the trachea

throacic fixation active closure facilitates the activities which demand highly elevated abdominal pressures (forced bowel movement and bladder and heavy lifting)

• the integration of:
• 1. the lungs
• 2. the vocal folds
• 3. the vocal tract

• serve as the power supply by providing aerodynamic subglottal tracheal pressure
•   -blows the vfs apart
•   -sets vfs into vibration

within the larynx provide the sounds source for phonation and they oscillate in a series of compressions and rarefactions, modulating the subglottal pressure and transglottal flow as short pulses of sound energy

serves as the resonating cavity, which shapes and filters the acoustic energy to produce the sound we recognize as human voice

• 1. muscles
• 2. mucous membranes
• 3. other connective tissue

3 levels of folds which serve as the sphincters providing both communicative and vegetative functions of the body

closure is multidimensional and closes horizontally (lateral to medial) and vertical (vertical compression)

the aryepiglottic folds, which is a strong fibrous membrane that connects the lateral walls of the epiglottis to the arytenoid cartilage complex

it folds posteriorly and inferiorly it separates the pharynx from the larynx and offer the first line of defense for preserving the airwary

• formed by the ventricular folds, which are not normally active during phonation but may become hyperfunctional during effortful speech production or extreme vegetative closure
•    -they are directly superior to the ventricle and the true vfs...forma a double layer of medial closure, if needed

to increase intrathoracic pressure by blocking the outflow of air from the lungs

during rapid contraction of the thoracic muscles (coughing, sneezing) or for longer durations when building up subglottic pressure to stablize the thorax during certain physical tasks (lifiting, emesis, childbirth, or defecation)

• the true vocal folds
• provide vibrating source for phonation for speech communication
• mechanically the larynx and vfs function as a variable valve modulating airflow as it passes through the vibrating vfs during phonation closing off trachea and lungs from foods and liquids during swallowing actions and providing resistance to increased abdominal pressure during effortful activities

the sound source that provides the speech signal

the resp power that the lungs and the abdominal and throacic musculature provide

• the diaphragm contracts (flattens)
• compresses the viscera
• simultaneously pulls the lungs downward
• as lung volume expands, air is drawn passively into lungs

• the diaphragm relaxes and rises back up to its resting position
• passive elastic recoil pushes air out of the lungs and through the vfs and vocal tract
• vfs are abducted in the paramedian position during quiet exhalation (no sound generated)

• the vfs adduct at midline, constricting the airflow stream as it exits the lungs aerodynamic energy sets the folds into oscillation, creating phonation
• without airflow, no sustained phonatory sound source can be achieved

interactive relationship btw the subglottal air pressure buildup and transglottal airflow rate passing through the vibrating vf valves

the excitation of air molecules when sound waves generated by the vfs travel through the supraglottic air column into the pharynx, oral and nasal cavities, and across articulatory structures such as the velum, hard palate, tongue and teeth

• acoustic energy (phonation) traveling through filter (vocal tract) modified in variable shape, size and constriction characteristics (artic gestures) is the basis
• theory underlies the understanding of the three components of speech:
• 1. glottal sound source
• 2. vocal tract filtering
• 3. resonating characteristics

The shape & size of the vocal tract & its constrictions have a direct influence on the quality & strength of the acoustic product radiated from the lips and perceived by listeners.

The sound of vf vibration w/out the supraglottic resonating cavity (i.e. intraoperative conditions or excised larynx studies) reveals a flat, atonal buzz, devoid of any “ring” and completely unrecognizable as human voice

• epiglottis
• thyroid
• cricoid

• arytenoids
• corniculates
• cuneiforms

• extrinsic=attach to a site on the larynx and to an external point
•     -primary function is to lift larynx
•     -also alter the shape and filtering characteristic of the supraglottic vocal tract, modifying vocal pitch, loudness and quality

• intrinsic=both end attached within the laryngeal cartilages
•     -primary function is to alter the shape and configuration of the glottis, by modifying the position and tension, and edge of the vfs
•     -two critical effects:
•        1.change the position of the cartilage framework that houses vfs
•        2. altering the shape and configuration of the glottis

• adduction
• abduction
• modifications in vf
•   1. length
•   2. tension
•   3. thickness

1)Ventilation 

2)Airway protection

3)Communication

4)Integral to maintaining a functioning laryngeal valve

• suprahyoid=above hyoid
• infrahyoid=below hyoid

raise the larynx by pulling the hyoid bone forward or backward and upward

• include:
•   -stylohyoid
•   -mylohyoid
•   -digastric (anterior and posterior bellies)
•   -geniohyoid

pull the hyoid boins and the larynx to a lower position in the neck

• include:
•   -thyrohyoid
•   -omohyoid
•   -sternohyoid
•   -sternothyroid

sternocleidomastoid forms broad sheath in the neck extending from sternum to the mastoid

the transverse interarytenoid which functions as single unit

the posterior cricoarytenoid, the sold abductor

the cricothyroid muscle which is innervated by the external branch of the superior laryngeal nerve

• epithelium
• superficial
• intermediate
• lamina propria (deep)
• vocalis muscle (deep)

lamina propria

process of bringing the vfs together to begin phonation, requires muscular action

coordinate adduction and onset of respiration so that they occur simultaneously

starting airflow before adducting the vfs

adduction of the vfs occurs prior to the airflow, like a cough

abduction of the vfs pull the vfs out to the airstram to reduce the tubulence using muscular action

• the purpose of adduction and abduction for speech
• measurement of sustained phonation

refers to the pattern of activity that the vocal folds undergo during a cycle of vibration

moving form one point in the vibratory pattern to the same point again

• refers to the differences in the mode of vibration of vocal folds
• 1. modal-first register, refers to the pattern of phonation used in daily conversation

second register, crackly popcorn quality, extremely low  in pitch and sounds rough

third and highest register, vf lengthen and become extremely thin and reedlike

• variation of modal phonation, medial compression is greatly increased
• breathy=vfs inadequately approximate

not really a phonatory mode, no vibration in the vfs

psychological correlate of frequency

refers to the pitch of vf vibration that is most appropriate for an individual

refers to the frequency of vibration of the vfs that is habitually used during speech

reflects the frequency of vibration of sustained phonation

the range of fundamental frequency for an individual and is calculated as the difference between the highest and lowest frequencies

fundamental frequency increase comes from stretching and tensing the vfs

• pyschological correlate of intensity
• increase subglottal pressure to increase vocal intensity

parameters of speech above the segment (phonetic) level (prosody-system of stress used to vary meaning; pitch, intonation-changes in pitch during speech; stress-syllable or word emphasis relative to an entire utterance)