Introduction To Phonation Flashcards
What is phonation
Not articulation, not initiation, VOCAL FOLD VIBRATION
What is phonation?
Production of “voice”
What is the sound source in phonation?
The larynx
What are the two types of phonation?
Voiceless and voiced
What are the three states of the glottis?
Closed
Open
Intermittent
What is the theory of voice production?
Aerodynamic myoelastic theory of phonation
What does aerodynamic mean?
Air pressure/movement forces
What does myoelastic mean?
Muscle and tissue
Aerodynamic myoelastic theory of phonation describes
Action of one cycle of pulsed energy
Cycle includes
Closed glottis-vocal folds subjected to pressure-vocal folds abduct-subject to Bernoulli effect-vocal folds adduct-closed glottis
What is the Bernoulli effect?
When gas/liquid is flowing through narrow space it accelerates
Moving liquid/gas
Lower in pressure
Pressure drop results in
Suction (rarefaction)
Bernoulli effect in speech
Pulmonic airflow
Narrowed glottis
Air pressure drops
Myoelasticity
The folds will part under pressure but will tend to push back (due to Bernoulli effect) once they have parted (Clark and Yallop)
Vocal folds subjected to pressure
Subject to Bernoulli effect
In the voice phonation type (I.e voicing) vocal folds can open and close
80-500 times per second
Vocal folds are
Versatile and have different settings. These can combine
What are the six phonation types?
Voice Breath Creak Whisper Harsh Falsetto
Voice is the
Main, normal phonation type used for vowels,consonants etc
Voice involves
Periodic opening and closing of vocal folds
Modal voice is a
Neutral mode of phonation that involves periodic vibration and has no audible friction noises. Other types combine with voice
When combined with voice, in breathy voice
Vocal folds vibrate without closing “flapping in the breeze” air flows through very fast
Voiceless phonation aka nil phonation
Glottis open
No audible noise from vocal folds
Low volume velocity
E.g f and s (noise only from oral cavity)
Whispery voice when combined with voice
Triangular opening (less than 25% of glottis) Hushing, turbulent noise (friction produced at glottis)
Creaky voice is also referred to as
Vocal fry/laryngealisation combines with voice
In creaky voice the vocal folds are
Strongly adducted: thickening of vocal folds
Creaky voice has
Low frequency cracking sound: 25-50Hz
Harsh voice has
Very strong tension of the vocal folds. Irregular vibration and amplitude
Falsetto has
High frequency of vibration. Vocal folds are stretched longitudinally and are thin at edges
What are the three auditory dimensions of phonation
Pitch
Loudness
Timbre
What is pitch?
Frequency of opening and closing of vocal folds
Big vocal folds results in
Slow pitch
Small vocal folds results in
Fast pitch
Pitch of vibration =
Fundamental frequency (F0)
In males fundamental frequency is
120Hz (hertz)
In females fundamental frequency is
220Hz
Fundamental frequency in child of ten years is
330Hz
Loudness is related to amount of
Sub-glottal pressure (greater=louder)
Loud voices have
Larger space between vocal folds during abduction and a longer adducted stage
Loudness is measured in
Decibels and referred to as amplitude
50dB
Quiet conversation
70dB
Loud conversation
130dB
Threshold of pain
Timbre refers to
Tone colour
Timbre is the differences in
Length of opening stage (opening quotient)
Low opening quotients are
Sharp and bright
High opening quotients
Are mellow
Perturbation
Is variations in pitch and loudness
Perturbation takes into account
Neurological, physiological and acoustic factors
A jitter is
A variation in pitch
With jitters, vibration cycles
Vary in frequency (over short-term speech signal)
Jitters occur in
Normal speech but markedly increased in dysphonic patients
What is a shimmer?
Variations in loudness. Variability in amplitude of vibration of vocal folds
English -Phonation types in languages communicate certain information but
Don’t affect meaning of words e.g boring, sexy
Change meaning in other languages
What are the results of ageing on phonation?
Low amplitude
Breathy phonation
F0 decrease (more in females than males)
Jitter and shimmer increase
A voice disorder is laryngitis which is
Interference of normal functioning of laryn affecting pitch and loudness and results in a breathy hoarse voice
Developmental disorders
Abnormal vocal folds/ paralysis voice mutation
Voice misuse results in
Swelling
Nodules
Polyps
