Laryngeal Anatomy & Phonation

Question 1

hyoid bone

Answer 1

the only bone in your larynx; the bone that rests above your thyroid cartilage

Question 2

epiglottis

Answer 2

a flap of cartilage above the vocal folds that retracts when we swallow and allows the tongue to direct food into the oesophagus

Question 3

thyroarytenoid

Answer 3

a muscle of the larynx that shortens the vocal folds, causing the voice to lower in pitch

Question 4

cricoarytenoid

Answer 4

a muscle of the larynx that tilts the thyroid cartilage downwards, causing the vocal folds to stretch and produce a higher pitch

Question 5

layers of the vocal folds

Answer 5

• vocalis muscle: innermost layer of the vocal folds; does not vibrate
• superior and inferior lamina propria
• epithelial layer (squamous epithelium): outermost layer of the vocal folds that vibrates during phonation

Question 6

What produces harmonics?

Answer 6

Harmonics are produced by the voice source, which is the vocal folds.
—Vocal folds come together and release at multiple points, creating harmonics
—f0 is the lowest frequency component of the voice, and it corresponds to H1
—f0 is the rate of vibration of the entire vocal folds

Question 7

breathy voice characteristics

Answer 7

• gradual or incomplete closure of the vocal folds
• large maximal glottal opening
• fast movement of the vocal folds
• more noise due to aspiration (in spectrogram)
• less abrupt closing of the vocal folds

Question 8

creaky voice characteristics

Answer 8

• sustained or complete closure of the vocal folds
• small maximal glottal opening
• slow movement of the vocal folds
• glottal pulses will look further apart than in modal voice (in spectrogram)

Question 9

Why do some harmonics get the label A1-A3 in a spectrum?

Answer 9

The harmonics that get labels A1, A2, A3, etc. are those closest to the formants. In other words, they are the harmonics that get amplified by the formants of the filter.
- H1 (f0) is not A1

Question 10

spectral tilt

Answer 10

the slope of a spectrum
- in modal voice, the spectral tilt is about 12 dB/octave; that is, the amplitude of the harmonics drops at a rate of 12dB/octave

Question 11

spectrum and spectral tilt in breathy voice

Answer 11

breathy voice is characterised by a greater spectral tilt (greater rate of drop-off of energy between harmonics)
- more energy in lower frequencies
- more aspiration noise

Question 12

spectrum and spectral tilt in creaky voice

Answer 12

creaky voice is characterised by a shallower spectral tilt
- shallow slope/spectral tilt
- higher frequencies get a boost because of abrupt closures of the vocal folds (more energy)
- not as much aspiration