spa3101 chapter 5

Non-speech laryngeal function

protective role, prevents entrance of foreign objects into the lungs by coughing, throat clearing, abdominal fixation

Abdominal fixation

impounds air in thorax to stabilize torso

Acoustics process of vibration determined by

elasticity and stiffness

Elasticity

property of material that causes it to return to original shape after displacement

Stiffness

strength of force within a material to return to original shape after distention

Inertia

a body in motion tends to stay in motion

Periodic waveform

repeats itself in a predictable fashion

Cycle

one point in a vibratory pattern to the same point again

Period

time to complete one cycle of vibration

Frequency

cycles per second

Frequency formula

f=1/t, frequency and period are inverse of each other

Hertz (Hz)

cycle per second, perceived as pitch

Intensity (on waveform)

increased amplitude of waveform, ratio of amount of pressure exerted

Sound pressure formula

P = F/A

Amplitude of a wave

degree to which waveform goes beyond x axis

Decibel

dB = 20 log, perceived as loudness, ratio of two sound pressure levels

Sound level meter

measures intensity of sound pressure emanating from source

Fundamental frequency

frequency of vibration of vocal folds

Vocal jitter/perturbation

cycle by cycle differences in vocal fold vibration

Vocal shimmer

cycle by cycle differences in intensity

Phonogram

shows interaction between intensity and frequency for individual

Pneumotachograph

airflow in face mask

Fiberendoscopy

view of vocal folds from above nasal cavity, also measures swallowing

Subglottal pressure measurement

via hypodermic needle through cricothyroid or estimated by intraoral pressure when vocal folds are open

Electroglottograph

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

Bernoullii effect

dictates that a constant volume flow of air or fluid, at a point of constriction there will be a decrease in air pressure perpendicular to the flow, an increase in velocity of the flow

Attack

start of phonation, adducting the vocal folds

Sustained phonation

vocal folds held in a fixed position in airstream, maintenance of a laryngeal posture through tonic contraction of musculature

Termination

abduct the vocal folds

Types of attack

simultaneous, breathy, glottal

Simultaneous vocal attack

adduction and onset of respiration at the same time

Breathy vocal attack

start significant airflow before adducting the vocal folds

Glottal attack

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

Termination of phonation

abduction of vocal folds, accommodates voiced and voiceless speech sounds

Sustained phonation

adduction and abduction for speech, maintenance of pressure, flow, vocal fold approximation

Vocal registers

differences in modes of vibration for phonation

Three major types of vocal folds registers

modal register or modal phonation, glottal fry or pulse, falsetto

Modal register or modal phonation

phonation used in daily conversation, most important for SLP, vocal folds open and close from inferior to superior, minimum driving force is 3-5cm for 5 sec

Glottal fry register or pulse register

crackly voice, rough and low in pitch, might indicate respiratory illness, vocalis is tense so vibrating margin is flaccid and thick, vocal folds spend up to 90% of time in approximation

Falsetto

increased pitch, vocal tension, lengthen and become thin

Whistle register

not mode of phonation, product of turbulence on edge of vocal fold

Two variations of modal phonation

pressed and breathy, whisper

Pressed

medial compression is increased, stronger, louder phonation, harsh

Breathy

inadequate vocal fold approximation, excessive airflow, may be due to organic condition

Whisper

vocal folds are partially adducted and tense, no voicing

Pitch correlate

frequency

Pitch and frequency relationship

pitch increases as frequency increases, vice versa

Optimal pitch

frequency of vibration most efficient for a pair of vocal cords, varies with gender and age

Habitual pitch

frequency habitually used by a person, effort to sustain phonation causes vocal fatigue

Pitch range

calculated as difference of lowest and highest frequency, reduced by pathology, increased through vocal training

Pitch changing comes from

stretching and tensing vocal folds using cricothyroid and thyrovocalis muscles

Intensity

physical measure of power or pressure, loudness psychological correlate

Increasing vocal intensity increases

sub glottal pressure and medial compression

In modal communication (percentage of stages)

50% opening, 37% closing, 13% closed

Clinical considerations of vocal jitter

people who are physically fit have lower perturbation values, individuals with neuromotor dysfunction have higher perturbation values than fit individuals

Maximum phonation time

duration of time an individual can sustain a phonation

Diadochokinesis

alteration of articulators producing single or multiple syllables per second

Suprasegmental aspects of communication

parameters of speech that are above the phonetic level, pitch and intensity play role, prosody

Prosody

system of speech used to vary the meaning of speech

Elements of prosody

pitch, intonation, loudness, stress, duration, rhythm

Myoelastic-aerodynamic theory

vibration of vocal folds depends on myoelastic component of muscle, aerodynamic component of airflow and compression through the compressed tube

posterior cricoarytenoid

additional muscle for tension, anchors

cricothyroid role

tension, pulls folds into gross posture

thyroarytenoid

additional muscle for tension, fine tuning

geniohyoid and genioglossus

additional muscles for tension, elevate larynx

During modal phonation the vocal folds open from ___. The folds close from ____.

inferior to superior, inferior to superior

The minimum subglottal driving pressure for speech is

3 to 5 cm

Presence of vocal nodules or other space-occupying laryngeal pathology may result in this phonation

breathy

To increase vocal intensity, one must _ subglottal pressure and _ medial compression

increase, increase

As vocal intensity increases, closed phase of the vibratory cycle

increases

frequency determined by factors of vocal folds

mass and tension

rate of vibration for males

120hz

rate of vibration for females

220 hz

rate of vibration for children

250 hz

transverse dimension

the anterior-posterior pattern of modal phonation that opens posterior-anterior and close anterior-posterior

vertical dimension

The inferior-superior pattern of modal phonation that opens inferior-superior and closes inferior-superior. The most consistent mode.

Muscles of adduction

lateral cricoarytenoid, transverse arytenoid, oblique arytenoid