The Normal The Normal VoiceVoiceCDIS 700CDIS 700

The Process of VoiceThe Process of Voice

Voice production relies on: Voice production relies on: RespirationRespiration PhonationPhonation ResonanceResonance

Each of these processes is not Each of these processes is not independent, and they may change independent, and they may change simultaneously.simultaneously.

RespirationRespiration The upper respiratory tract (respiration, The upper respiratory tract (respiration,

eating, articulation, resonance, and eating, articulation, resonance, and phonation)phonation) Nasal cavityNasal cavity Oral cavityOral cavity PharynxPharynx LarynxLarynx

The lower respiratory tract (breathing for life The lower respiratory tract (breathing for life and for speech)and for speech) TracheaTrachea BronchiBronchi Lungs (with bronchioles/alveoli)Lungs (with bronchioles/alveoli)

The Respiratory SystemThe Respiratory System

How the Respiratory How the Respiratory System WorksSystem Works

External, musculoskeletal forces must act upon the External, musculoskeletal forces must act upon the respiratory tract for respiration.respiratory tract for respiration.

When the ribcage expands and contracts, so do the When the ribcage expands and contracts, so do the lungs, and also the volume of air in the lungs.lungs, and also the volume of air in the lungs.

Boyle’s law: Pressure and volume are inversely Boyle’s law: Pressure and volume are inversely related.related. When lung volume is increased, air that is external to the When lung volume is increased, air that is external to the

lungs has a higher pressure relative to the air contained lungs has a higher pressure relative to the air contained within the lungs. within the lungs.

This air pressure differential causes an inward rush of air This air pressure differential causes an inward rush of air through the respiratory tract (inspiration) and into the lungs through the respiratory tract (inspiration) and into the lungs so as to equalize air pressure within and outside the lungs.so as to equalize air pressure within and outside the lungs.

A decrease in lung volume results in an increase in air A decrease in lung volume results in an increase in air pressure in the lungs, causing air to flow in an outward pressure in the lungs, causing air to flow in an outward direction (exhalation).direction (exhalation).

Inspiration MusclesInspiration Muscles

The primary muscle of inspiration is the diaphragmThe primary muscle of inspiration is the diaphragm Under primary control of the autonomic nervous system Under primary control of the autonomic nervous system

with motor pattern for breathing generated by the CNSwith motor pattern for breathing generated by the CNS

Accessory muscles:Accessory muscles: External intercostal muscles: elevate/expand the External intercostal muscles: elevate/expand the

ribcage; used in deep breathingribcage; used in deep breathing Aspects of the internal intercostal muscles also Aspects of the internal intercostal muscles also

contribute to the way the external intercostals elevate contribute to the way the external intercostals elevate the ribcage.the ribcage.

Muscles in the arms and shoulders employed to assist Muscles in the arms and shoulders employed to assist in elevation of the thorax. in elevation of the thorax.

Neck muscles: sternocleidomastoid, scalenes (clavicular Neck muscles: sternocleidomastoid, scalenes (clavicular breathing)breathing)

Expiratory MusclesExpiratory Muscles

Expiration is Expiration is generallygenerally passive. passive. Passive factors include the elasticity Passive factors include the elasticity

of the lungs, ribs untorquing, visceral of the lungs, ribs untorquing, visceral recoil, and gravityrecoil, and gravity

When air is forced out of the lungs, When air is forced out of the lungs, the ribcage is pulled down by the:the ribcage is pulled down by the: Internal intercostal musclesInternal intercostal muscles Transverse thoracic musclesTransverse thoracic muscles Abdominal musclesAbdominal muscles

Lung Volumes and Lung Volumes and CapacitiesCapacities

Tidal volume: amount of air inspired and expired during Tidal volume: amount of air inspired and expired during a typical respiratory cycle.a typical respiratory cycle.

Inspiratory reserve volume: maximum volume of air that Inspiratory reserve volume: maximum volume of air that can be inspired at the end of a tidal inspiration.can be inspired at the end of a tidal inspiration.

Total lung capacity: the total volume of air that can be Total lung capacity: the total volume of air that can be held in the lungs and airwaysheld in the lungs and airways after a maximum after a maximum inspiration.inspiration.

Expiratory reserve volume: maximum volume of air that Expiratory reserve volume: maximum volume of air that can be expired at the end of a tidal expiration.can be expired at the end of a tidal expiration.

Residual volume: volume of air that remains in the lungs Residual volume: volume of air that remains in the lungs after a maximum expiration and cannot be expelled. after a maximum expiration and cannot be expelled.

Vital capacity: total amount of air that can be expired Vital capacity: total amount of air that can be expired from the lungs and air passages following a maximum from the lungs and air passages following a maximum inhalation.inhalation.

Respiration and SpeechRespiration and Speech

When at rest, the length of expiration is slightly longer When at rest, the length of expiration is slightly longer

than that of inspiration.than that of inspiration.

When we speak, we tend to place more force on the When we speak, we tend to place more force on the

muscles of inhalation, but we do so very quickly. We then muscles of inhalation, but we do so very quickly. We then

speak on exhaled air for longer periods of time.speak on exhaled air for longer periods of time.

Normal speakers use passive exhalation, then tidal volume, Normal speakers use passive exhalation, then tidal volume,

and then the expiratory reserve.and then the expiratory reserve.

Speaking with normal air volumes (e.g., passive Speaking with normal air volumes (e.g., passive

exhalation/tidal volume) tends to result in the best voice. exhalation/tidal volume) tends to result in the best voice.

Too much air pressure, or too little, and the voice becomes Too much air pressure, or too little, and the voice becomes

strained.strained.

References and Resources

Make your own spirometer: http://www.tryscience.org/teachers/files

/handout_lung.pdf Learn more about pulmonology:

http://en.wikipedia.org/wiki/Pulmonology

Some examples of how Boyle’s law works: http://www.youtube.com/watch?v=x5oJ

9nOY0_c http://www.youtube.com/watch?v=NB1

aCBId6qA&feature=related