Respiration
 Phonation
 Resonation

 The Pulmonary System

 Upper airway
 Laryngeal structures
 Lower airway (trachea, bronchial tubes, bronchioles & alveolar sacs)
 Thoracic cavity - thoracic vertebrae, ribcage, connecting muscles
 Diaphragm muscle

Air is the medium for propagation of sounds

 Air forced through constrictions along the respiratory tract generate sounds

 Flow - volume of air passing through tube or duct per second

 Pressure- force distributed over a surface

•  Absolute pressure
•  Relative pressure

•  equivalent to alveolar pressure which is the pressure of air within the lung tissue
•  At resting level lung pressure equals atmospheric pressure

•  Flow begins when pressure within lungs is either above or below atmospheric pressure
•  Air flows from region of higher relative pressure (positive) to region of lower relative pressure (negative)
•  Inspiration - lung volume increases, lung pressure drops, air rushes in
•  Expiration - lung volume decreases, lung pressure increases, air flows out

•  Inspiratory muscles - diaphragm, external intercostals & if necessary the shoulder and neck muscles
•  Expiratory muscles - 4 abdominal muscles and internal intercostals
•  Passive breathing - active contraction of inspiratory muscles followed by passive forces (elastic recoil of lung tissue, gravity, untorquing of ribs) that reduce lung volumes
•  To extend expiration - active contraction of muscles of expiration after passive forces dissipate

•   Larynx - specifically vocal folds function as a valve to regulate airflow
• Vocal folds offer slight resitance to airflow
• Glottis closes slightly for high lung pressures and opens wider for low lung pressures which helps keep pulmonary airflow more constant
• This regulation autonomically controlled by nervous system

Total Lung volume
Vital capacity - total amount of air that can beexpired after a maximum inhalation
Residual volume - air that remains in lungs after maximum exhalation

 
 Vital capcity
•  Tidal volume - amount of air breathed in and out during normal respiratory cycle -typically 10 - 15% of vital capacity
•  Inspiratory reserve - maximum air inhaled after tidal volume
•  Expiratory reserve - maximum air exhaled after tidal volume

•  Adducted vocal folds provide increased resistance to airflow
•  May need to activate abdominal muscles to get greater lung pressure
•  Also need to extend the expiratory phase
•  For longer phrases, will use more of active forces after passive forces are depleted

•  Goal is for respiratory patterns to be facilatory for vocalization
•  Best vocal quality associated with mid air-pressure and mid lung-volume levels
•  Teach shorter phrasing patterns to avoid low pressure and flow situations
•  Use increased abdominal contraction to increase power rather than tightening the laryngeal valve

• Production of voice is dependent on the interplay between muscular forces and aerodynamic events
• Myoelastic-aerodynamic theory of vocal fold vibration
• Contraction of intrinsic muscles determine the compliance, length, elasticity and mass of the vocal folds; also approximate vocal folds to phonatory position
• Aerodynamic forces from build up of air pressure below the vocal folds force the adducted vocal folds open; Bernoulli effect aids muscular forces in closing vocal folds

•  Also important component of vocal fold vibration/voice production
•  Explained by Body-Cover model of vocal fold vibration
•  Different vibratory properties of vocal fold layers
•  Vertical phase difference
•  Loss of mucosal wave results in changes in voice quality, increases in PTP
•  Conditions that change density relationships between cover and body result in decreases in mucosal wave

 

•  Determined by the vibratory rate (number of open/close cycles per second)
•  Perceived as the pitch of the voice
•  Rate of vibration related to thickness, length and elasticity of vocal folds
•  Increases in f0 also associated with increases in subglottal pressures, medial compression and glottal airflow rates

 

•  Defined by Hollien as range of consecutive f0s that can be produced with a perceptually distinct voice quality
•  Differ also with regard to laryngeal events such as vocal fold status, vibratory pattern, driving pressure and mean phonatory airflow
•  Three distinct speaking voice registers (singers identify more)
•  Pulse - lowest range of frequencies; glottal fry
•  Modal - most used register; more continuous tone than pulse
•  Loft - falsetto - upper frequencies; thin, maximally elongated folds

•  Related to changes in subglottal and transglottal air pressure
•  Perceived as loudness changes
•  Average intensity during speech - 75 - 80 dB; dynamic range - 40 - 65dB
•  Modified by
•  Subglottal adjustments
•  Laryngeal adjustments
•  Supralaryngeal adjustments

 

•  Way in which the laryngeal tone is initiated affects perceived voice quality
•  3 basic vocal or phonatory attacks
•  Simultaneous - exhalation and vocal fold approximation occur at same time
•  Hard glottal attack - vocal folds adducted tightly as exhalation begins
•  Breathy or aspirate attack - initiation of exhalation before adduction
•  Asynchronous movement of vocal folds affects quality
•  Supraglottal resonance variations - constriction, vertical & horizontal tone focus

•  Vibrating sound source excites air-filled chambers and walls of the chambers
•  Serves to selectively amplify vibrations
•  Most quality and loudness characteristics of human voice are a product of the resonating cavities
•  Resonance cavities can be altered in size, configuration & tightness

 

•  Pharynx - 2 layers of muscles
•  Pharyngeal constrictors - outer layer
•  Stylopharyngeus, salpingopharyngeus & palatopharyngeus
•  Oral Cavity
•  Nasal Cavity
•  Velum
•  Levator palatini
•  Tensor palatini
•  Uvulus
•  Palatoglossus
•  Palatopharyngeus

•  Coupling/uncoupling of nasal cavity
•  Velum elevates
•  Lateral walls of pharynx move medially
•  Tongue position changes size/shape of oral cavity
•  Ratio of oral to pharyngeal cavity
•  Membranes of pharynx and tightness of pharyngeal constrictors

•  Decreases in vital capacity
•  Loss of elasticity in thoracic skeleton
•  Muscular weakness
•  Anecdotal reports of reduction in loudness in the elderly - not demonstrated objectively

•  Cartilages calcify and ossify
•  Changes in cricoarytenoid joints limiting approximation of vocal folds
•  Changes/breakdowns in layers of the lamina propria
•  Laryngeal bowing - presbylaryngeus

•  In 5th decade male fundamental increases, while female f0 decreases
•  Decline in pitch control
•  Reduction in pitch range
•  Perception of vocal roughness, aperiodicity and breathiness