Phonation Flashcards
VF’s _____ via PCA muscles during inhalation :: VF’s ______ via LCA, IA, TA muscles
abduct :: adduct
VF’s open bottom to top. T or F?
True; VF’s open at bottom first; then the opening proceeds to top of the VF’s. As top opens, bottom begins to close.
The movement of the VF’s opening and closing creates a ___________.
vertical phase difference
The MUCOSAL WAVE occurs as a result of?
The VF’s vibrating;
Mucosal Wave
VF cover/mucosa appears to slide over the VF body –> slides during vibration & produces a wave in the mucosa.
Where does the Mucosal Wave appear to travel?
Across the superior surface of the VF’s about 1/3 to 2/3’s of the way from the lateral edge of the fold.
What can affect normal vibration or diminish wave?
Scarring or stiffening by disease or surgical procedure.
When a gas/liquid flows through a constricted passage causing the velocity to increase while outward pressure of the gas molecules decreases is?
The Bernoilli Effect
Re: The Bernoulli Effect
The pressure drop is ________ to the direction of the blow.
perpendicular
Bernoilli Effect and the VF’s
- subglottal pressure forces VF’s apart
- narrow space created in glottis causes velocity of air molecules to increase
- increase in air molecule velocity= decrease in pressure between VF’s
- decrease in pressure causes walls of glottis to come together (+natural elastic recoil of VF’s)
Myoelastic refers to ….
the laryngeal muscle activity that occurs during phonation and the effects of laryngeal muscle activity on the elasticity of VF’s.
Aerodynamic refers to …
the aerodynamic determinants of the vibratory cycle (ie: opening & closing phases of vibration)
What are the 2 aerodynamic foces that are determinants of VF vibration?
- Subglottal Pressure (Ps)
2. Negative pressure due to Bernoulli effect
What are the 3 main points of VT Inertance?
- Sustained VF vibration is driven partly by transglottal pressure & supraglottic pressure
- Ps increases, VFs open, glottal airflow increases from sluggish to rapid b/c pressure builds up between & above VF’s.
- Glottis closes & forward momentum & acceleration of VT air column continues, Airflow through glottis can’t keep up & this creates suction, which further closes the glottis.
The build up & release of supraglottic pressure is delayed in respect to opening & closing of VF’s creates?
Vocal Tract Inertance
What 2 mechanisms control frequency?
- the cover model
2. the body cover model
The Body Cover Model
Activity of the TA muscle can either increase or decrease frequency depending on the depth of VF vibration & level of activity in the CT muscle.
During normal to high intensity speech or singing in chest or head regiser, the _____ and _____ are in vibration.
VF body and VF cover
What type of phonation results in increased amplitude & depth of vibration?
High intensity (loud) phonation
*(TA muscle is likely to be involved in vibration)
What happens when the TA contracts during loud phonation?
The overall stiffness/tension of VFs will increase & frequency will increase.
(as long as CT muscle is not at its maximum)
What happens when CT activity is at its maximum during loud phonation?
Frequency will decrease due to TA contraction. TA will shorten VFs & will decrease overall VF stiffness.
Increased intensity = increased amplitude of vibration –> VF’s to lengthen & VF tension to increase –> increases frequency. This is also known as?
Dynamic Strain
Non linear tissue movement
Convergent glottis: VFs open from bottom to top, transglottal pressure is positive, net tissue velocity is outward & air molecules converge.
Divergent glottis: Vfs close bottom to top, transglottal pressure is negative, net tissue velocity is inward & air molecules diverge.
*asymmetry in air pressure (+ for VF opening & – for VF closing) that is essential for self sustained vibration.
What type of sound is generated by the VF’s?
It generates a quasi-periodic complex tone.
What are the 3 things that control intensity?
- Below the larynx- increased Ps
- At the larynx- increased VF adduction
- above the larynx- VT adjustments
What is vocal quality determined by?
It is determined by the periodicity of VF vibration & degree of glottic closure
