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)Vocal cords –Length –Mass (thickness) –Tension –Normal Vocal Cord Images/VideosNormal Vocal Cord Images/Videos

Cultures The Jimi Hendrix of MongoliaMongolia Incredible Human MachineIncredible Human Machine Steven Tyler Wall of SoundWall of Sound Naturally 7 Dr. Patricia Kuhl: Linguist Genius of BabiesLinguist 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 F o (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 F o of an individual during normal conversation or during oral reading

VC Fundamental Frequency SFF variations: –Age –Gender –Emotions –Sentence type –Disease –Medications

SFF and Age Infants Hz Children Hz Pubescence120 Hz - males; 220 Hz - females Seniors162 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: –F o SD Normal conversation Hz Varies by age, gender, emotions –Semitones=pitch sigma (2-4 semitones) –Range – difference between highest and lowest F o 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 Infantsgreatest range Hz Children Hz Adolescents64-95 Hz Seniors 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 dB SPL –Prosody of speech –Emotions –Social situations –Health

Medications Adversely Affecting Voice 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 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 disphoniaSpasmodic disphonia –Spasmodic disphoniaSpasmodic disphonia