Laryngeal Physiology

Valving for Speech 4. Mechanics of voice control: *Voice can be controlled for: 1) Pitch 2) Loudness 3) Quality 4) Register in which voice is produced

Valving for speech cont... Mechanics of voice control: 1) Register: -The mode of adjustment of the larynx by which voice is produced. -speech is produced almost always in one register, whereas singing many more. Three main registers: 1) modal 2) falsetto 3) pulse

Modal Register Register used for speech Produces relatively low fund. frequencies (Fo) Also called “chest” or “heavy” register Generally vocal folds are short & thick Stiffness of v.f.’s is relatively low Amplitude of vibration is large Folds tend to completely close Signal is rich in harmonics

Falsetto Register Also called “light” register Produces a higher range of Fo’s Vocalis is lax Cricothyroid activity adjusts length Longer, thinner, stiffer folds (compared to register) Small amplitude of vibration Incomplete closure of v.f.’s Fewer higher harmonics Shutter-like appearance

Pulse Register Also known as “vocal fry” or “glottal fry” Low frequency register Sounds rough or deep Used infrequently for speech or singing Short, thick & lax vocal folds Complex vibratory pattern

Valving for Speech -Physical correlate is fundamental frequency, Mechanics of voice control cont.: 2) Pitch: -Physical correlate is fundamental frequency, -Women’s Fo=180-250 Hz; -Men’s Fo= 100-150 Hz -Pitch is and perceived variable, -Average Fo changes during the first 20 years, than stabilizes.

Pitch: Vocal Fold Thickness Pitch is determined by rate of vibration, In men folds are longer & thicker, v.f. thickness changes correlate better to pitch than length, But...stiffness from lengthening is the main determiner of pitch. Low Pitch High Pitch

Valving for Speech Mechanics of voice control cont.: 3) Loudness: - The listener's response to the amount of energy in a sound. -Physical correlate is intensity, -Loudness varies with the volume & velocity of air, higher fundamental the greater the loudness,

Loudness cont... Greater the volume velocity of each glottal pulse the greater the loudness, Intensity increases as alveolar and subglottal pressures increases, inc. air escapes Glottal resistance increases with intensity (pressure can not rise without an equal increase in resistance) Louder the tone, longer vocal folds stay closed.

Loudness Soft volume velocity Loud Alveolar pressure

Valving for Speech Mechanisms of voice control cont.: 4) Quality: -distinctive characteristics of a tone, exclusive of its pitch & loudness, -3 distinct qualities: 1) Breathiness 2) Harshness 3) Hoarseness

Breathiness Glottal adjustment offers enough resistance for vibration, Laryngeal adjustments: 1) in the front- v.f.’s close but don’t touch, however close enough to generate tone and... 2) in the back- glottal chink present which lets air escape to an excessive extent and... 3) Excessively large glottal area in each cycle (large volume of air flow at low velocities) Folds barely close folds, low intensities

Harshness Also called “roughness” Associated with “gravely” voice Cause is irregularity in v.f. vibration Duration irregularity= “jitter”(pitch perturbation) Intensity variability= “shimmer”

Hoarseness Combines both breathiness & harshness Results from irregular vibratory patterns in which leakage is excessive Early warning sign of vocal pathology Aperiodic vibration

Outside reading: (Textbook in library) Reading/Assignments Outside reading: (Textbook in library) Perkins, W.H. & Kent, R.D. (1986). Functional Anatomy of Speech, Language & Hearing, Allyn & Bacon Pgs. 100-111