the larynx and phonation Flashcards
biological function of larynx (3)
prevents unwanted objects from entering the lung
- allows us to expel unwanted objects by coughing
- assists in breathing
larynx anatomy- main cartillages (4)
- cricoid
- thyroid
- 2x arytenoid
- epiglottis
diagram 3- the larynx (a-g)
a= epiglottis
b= hyoid bone
c= thyroid cartillage
d= arytenoid cartillage
e= cricoid cartillage
f= trachea
g= cricothyroid muscle
what is the cricoid cartilage?=
a ring-like cartillage thats attached to the TOP of the trachea
what is the thyroid cartillage?>
shield-like structure made up of right and left plates that fuse together to form a notch known as the ‘thyroid prominence’ (aka A’s A)
what is the arytenoid cartillage?
rests on top of the cricoid cartillage and attaches to the vocal folds
what is the epiglottis?>
flap behind the thyroid that projects upwards behind the tongue
(>prevents food going down trachea when swallowing)
diagram 4- glottiss (a-c)
a= vocal folds
b= thyroid cartilage
c= arytenoid cartilage (AC)
diagram 5- the larynx top view (a-g)
a= muscular processes
b= thryoid notch
c= thyroid cartillage
d= cricoid cartillage
e= vocal ligaments
f= vocal processes
g= arytenoid cartillage
what are the vocal processes?>
small protrusions on the arytenoids
- are also attachments for the vocal folds
what are the vocal ligaments?
inner part of the vocal folds that connect between the thyroid notch and vocal processes
what are the muscular processes?>
these stick out behind the arytenoids
these attach to some of the intrinsic muscles of the larynx
what is phonation>
the process by which moving air is converted into (VF) vibrations
>(includes voicing sound in throat)
what is modal phonation (/modal voicing)?>
- where the vocal cords are OPEN wide & close tightly, spending equal amounts of time open & closed
- the VF open from the bottom upwards
theories of phonation>
- the neurochronaxic theory
- the myoelastic aerodynamix theory
what is the neurochronaxic theory of phonation?>
- vocal fold vibrations are caused by deliberate contractions of the muscles
what are the problems with the neurochronaxic theory of phonation
susbequent evidence show that vocal folds cant activley contract quickly enoguh for theory to be correct (deliberate contractions of muscles)
what is the myoelastic aerodynamic theory of phonation
vocal fold vibrations are caused by the ‘elastic’ properties of the vocal folds & by aerodynamics
what is the benoulli effect?>
as an airflow increases in speed, it decreases in pressure
how is the pitch of voicing changed?
by changing length of vocal folds (this affects how quickly they can vibrate)
longer vocal folds=
greater tension
vibrate more quickly (higher pitch)
shorter vocal folds=
lesser tension
vibrate less qucikly (lower pitch)
what is the cricothyroid muscle?
located between thyroid & cricoid cartillages which cana be contracted tto reduce distance between them (adjusts length of VF–>tilts down/stretches)
phonation types=
refers to different states of the glottis during phonation (a range of glottal states that are in-between completely open (voiceless) and completely closed (glottal)
