Phonation Physiology

key functions of the larynx, list if VF are abducted or adducted for each

- breathing (VF abducted)

- speech/voice (VF adducted)

- coughing (Vf first adducted, then blown abducted)

- swallowing (VF adducted)

function: phonation

- voicing

- VF vibration

- has elasticity

- includes the bernoulli effect

the bernoulli effect

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

- simple terms: a wider area has a slower velocity and a higher pressure, but as soon as we hit that point of constriction, the velocity increases and pressure decreases

- think of traffic jam before a tunnel

VF open and close from...

- inferior to superior

define a cycle of vibration

- a movement from one position to the same position again

- your VF goes from closed VF, opens, then comes back to closed again. that is 1 cycle

the VF are always at the ______ during phonation

- midline

3 steps of sustained phonation

- begins with a vocal attack

- maintains VF approximation

- termination (VF abduction)

vocal attack

- VF are moving towards the midline to close the glottis

3 things sustained phonation needs

- subglottal pressure

- tissue elasticity

- constriction

sustained phonation is NOT a _____ ________

- muscular effort

______ is the psychological correlate of frequency

- pitch

pitch vs. frequency

- pitch: our own perception

- frequency: scientific and measurable

what is frequency

- number of cycles of vibration/second

the relationship between pitch and frequency is _______

- direct/proportional

- as pitch increases, frequency increases

- as pitch decreases, frequency decreases

optimal pitch

- frequency of vibration that is most efficient for a pair of VF

- a level that works best for that set of VF

habitual pitch

- the pitch that a person usually uses in everyday conversation

______ and ______ should be around the same

- optimal pitch and habitual pitch

what happens with optimal and habitual pitch when someone has a voice disorder?

- their habitual pitch is higher or lower than their optimal pitch

pitch range

- the difference between the lowest and highest pitch a person can produce

2 mechanisms that change F0 (aka fundamental frequency)

- tensors

- relaxers

tensors and F0

- F0 increases

- stretch VF

- results in thinner and tenser VF

relaxer and F0

- F0 decreases

- relaxes VF

- results in thicker and laxer VF

what does F0 stand for

- fundamental frequency

- the number of vibration cycles

if the VF are thicker, it takes _______ to complete one cycle

- longer

primary/most important muscle we use to change our pitch

- cricothyroid

a lower pitch means that the VF are...

- thicker

______ is the psychological correlate of intensity

- loudness

intensity vs. loudness

- intensity: physical measure of power or pressure

- loudness: how we perceive power/pressure

2 ways to increase intensity

- increase medial compression

- increase subglottal pressure

what does it mean to increase medial compression

- how hard we are closing our VF during phonation

- think of slapping your hands together instead of doing it softly

what does it mean to increase subglottal pressure

- the amount of force we use to close the glottis

why is increasing subglottal pressure to increase intensity better than increasing medial compression?

- our VF (epithelial tissue) is very delicate

- if we slap them really head, it's going to cause wear and tear, which leads to hoarseness, which in turn leads to your voice sounding different