Transcript Chapter 3 Vocal Folds

Chapter 2
Resonance
Perry C. Hanavan, Au.D.
Question
What is meant by phonation?
A. Whispered speech sound
B. Voiced speech sound
C. Produce a nasal sound
D. Use your lips to produce sound
E. I don’t know
Vocal Cords
• Phonation
• Vocal cords (variables)
– Length
– Mass (thickness)
– Tension
– Normal Vocal Cord Images/Videos
Cultures
The Jimi Hendrix of Mongolia
Incredible Human Machine Steven Tyler
Wall of Sound Naturally 7
Dr. Patricia Kuhl: Linguist Genius of Babies
Question
Who has the longer vocal folds?
A. Men
B. Women
C. Young boys
D. Young girls
E. Cats
Question
Whose pitch rises as they age?
A. Men
B. Women
C. Young boys
D. Young girls
E. Cats
Question
When does the most dramatic change in
phonation occur?
A. Childhood
B. Pubescence
C. Adulthood
D. Elderly
E. Infancy
VC Fundamental Frequency
• Fo (fundamental of vocal fold vibrations)
– Vocal folds/chords generate a fundamental and
harmonics
– Fundamental is not audible due to vocal tract
resonance
– Although Fo not audible, the listener perceives the
audible harmonics as the Fo (perceptually as pitch)
• SFF = speaking fundamental frequency
– Average Fo of an individual during normal
conversation or during oral reading
VC Fundamental Frequency
• SFF variations:
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Age
Gender
Emotions
Sentence type
Disease
Medications
SFF and Age
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Infants
Children
Pubescence
Seniors
350-500 Hz
270-300 Hz
120 Hz - males; 220 Hz - females
162 Hz - males; 177 Hz - females
Gender
• Pubescence
– More dramatic change in males than females
SFF
• Seniors
– SFF increases in males
– SFF decreases in females
Adult Gender Differences
• Male vocal folds: 17 mm and 25 mm (0.67" to
1.0") in length.
• Female vocal folds: 12.5 mm and 17.5 mm (0.5"
to 0.7") in length.
Frequency Variables
• Stress and accent of sounds in speech
• Prosody features of speech
• Measured by:
– FoSD
• Normal conversation 20-35 Hz
• Varies by age, gender, emotions
– Semitones=pitch sigma (2-4 semitones)
– Range – difference between highest and
lowest Fo in sample of speech
Question
Whose voice has the greatest frequency
variation?
A. Infants
B. Children
C. Adolescents
D. Adults
E. Seniors
Range of Freq. Variability
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Infants
Children
Adolescents
Seniors
greatest range -1202 Hz
150-190 Hz
64-95 Hz
78-101 Hz
Question
What can influence our voice intensity?
A. Prosody of speech
B. Emotions
C. Social situations
D. Health
E. All the above
Amplitude
• Normal 65-85 dB SPL
– Prosody of speech
– Emotions
– Social situations
– Health
Medications Adversely
Affecting Voice
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Antidepressants
Muscle relaxants
Diuretics
Antihypertensives (blood pressure medication)
Antihistamines (allergy medications)
Anticholinergics (asthma medications)
High-dose Vitamin C (greater than five grams per day)
Angiotensin-converting-enzyme (ACE) inhibitors (blood pressure
medication) may induce a cough or excessive throat clearing.
Pill may cause edema in the vocal cords due to estrogen.
Estrogen replacement therapy post-menopause may have effect.
Low level of thyroid replacement medication in patients with
hypothyroidism.
Anticoagulants (blood thinners) may increase chances of vocal cord
hemorrhage or polyp formation in response to trauma.
Medical Conditions
Affecting Voice
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Poor health
Laryngitis
Laryngopharyngeal Reflux Disease (LPRD)
Voice misuse and overuse
Benign vocal cord nodules
Vocal Cord Hemorrhage
Vocal Cord Paralysis and Paresis
Neurologic related
Laryngeal cancer
Voice Disorders
• Diplophonia
– Muscle Tension Dysphonia (MTD) is a general term to describe
excessive and unnecessary tension of laryngeal muscles during
voicing.
– MTD is often referred to by many different names including hyperfunction, functional dysphonia, ventricular or false vocal fold
compression, etc.
– MTD is thought to be a compensatory mechanism in the presence of
underlying laryngeal pathology.
– Symptoms often include a sensation of excessive laryngeal tension and
strain, vocal fatigue, and hoarseness.
• Neurologic
– Spasmodic disphonia
– Spasmodic disphonia