1. CSD 2230
HUMAN COMMUNICATION
DISORDERS
Topic 7
Speech Disorders
Voice Disorders

2. Pitch
The perceptual counterpart to fundamental
frequency associated with the rate of vocal
fold vibration
Average fundamental frequencies
 Men 130 Hz
 Woman 250 Hz
 Children 500 Hz
Habitual pitch
Optimal pitch

3. Changes in the Larynx
with Development
At birth, the infant larynx is at C3
Larynx reaches C6 by 5 years and C7 by
15-20 years
At birth, the vocal folds are 3 mm long
Growth rates
 0.4 mm/year for girls
 0.7 mm/year for boys
Puberty

4. Inflection
The cricothyroid and thyroarytenoid
muscles work to tense the glottis which
causes the vocal folds to become
stretched and vibrate faster, thereby
causing pitch to rise

5. Vocal Intensity
Changes in vocal intensity are perceived
as changes in loudness
Changes in vocal intensity require the
vocal folds to stay together longer
during their closed phase of vibration

6. Voice Disorders
About 3-6% of school-aged children and
3-9% of adults are affected
The five perceptual signs

7. Disorders of Vocal Pitch
1. Monopitch: a voice that lacks normal
inflectional variation and to change
pitch voluntarily
2. Inappropriate pitch: a voice judged to
be outside the normal range of pitch
for age and/or gender
3. Pitch breaks: sudden, uncontrolled
changes in pitch

8. Disorders of Vocal Loudness
1. monoloudness: a voice that lacks
normal variations of intensity and the
inability to change vocal loudness
voluntarily
2. loudness variation: extreme variations
in vocal intensity in which the voice is
either too soft or too loud

9. Disorders of Vocal Quality
1. Hoarseness/roughness: a voice that lacks
clarity and is noisy
2. Breathiness: the perception of audible air
escaping thru the glottis during phonation
3. Tremor: variations in pitch and loudness of
the voice not under voluntary control
4. Strain and struggle: related to problems
with initiating and maintaining voice

10. Nonphonatory Vocal
Disorders
1. Stridor: noisy breathing or involuntary
sounds that accompany inspiration
and expiration
2. Consistent aphonia: a persistent
absence of voice perceived as
whispering
3. Episodic aphonia: uncontrolled and
unpredictable aphonic breaks in voice

11. Etiologies
 Vocal abuse
 Medical conditions
 Psychiatric conditios

12. Vocal Abuse
Structural damage to vocal fold tissue which
affects vibration
1. Vocal nodules: localized growths on the vocal folds
 Hoarseness and breathiness
 Audio example
2. Contact ulcers: reddened ulcerations on the vocal folds
 Hoarseness, breathiness, excessive throat clearing, vocal
fatigue
 Audio example
3. Polyps: fluid-filled lesions on the vocal folds
 Hoarseness, breathiness, roughness
4. Acute and chronic laryngitis: inflamation of the vocal folds
 Mild hoarseness, aphonia

13. Medical Conditions
1. CNS disorders
 Dysarthria from Parkinson’s
 Vocal fold paralysis
 Pseudobulbar palsy
 Huntington’s chorea
 Spastic dysphonia
 Audio example
2. Organic disease
 Laryngeal cancer
3. Laryngeal trauma

14. Psychiatric Conditions
Conversion disorders result from the
psychological suppression of emotion
 Aphonia
 Audio example