Respiratory Physiology

Breathing For Speech Air under pressure Air pressure forces vocal folds apart To achieve pressure it requires air flow to be resisted

Pressure Requirements: Loudness Produce a soft tone followed by a loud tone: Observe the increased pressure needed to increase loudness For speech: resist the flow of air just enough to produce the desired sound How do you achieve the necessary pressure for speech? Adjusting the expiratory force of the resp. pump Adjusting airway resistance

Pressure Requirements: Speech Adjusting expiratory pressure & airway resistance: Both necessary to generate pressure Affect air reservoir in lungs- Alveolar pressure Resulting pressure build up in trachea under folds- Subglottal Pressure Variations in airway resistance to expiratory forces determine pressure

Respiratory Pressures Expiratory Force Alveolar Pressure Pressure Increases Low Pressure High Pressure Tracheal Pressure

Stress & Articulation Speech is dynamic (not monotone) need more than steady resp. alveolar pressure Stress varies syllable to syllable Stress variations made by adjustments in: Pitch Loudness Duration

Stress & Articulation Loudness of syllable= Varies with changes in alveolar pressure (small muscle contractions) Intensity varies from sound to sound Vowels more intense than consonants Sound intensity controlled by changes to airway resistance that alter intraoral pressure Example: “Too” - Pressure rises for “t”

Stress & Articulation 3 aspects of speech require control of pressure: Loudness level of phrase= Interaction of passive & active expiratory forces Stress at syllable level = Small expiratory contractions or relaxation's of expiratory muscles (momentary changes in alveolar & subglottal pressure) Intensity variation sound to sound= Instant to instant changes in airway resistance causing momentary fluctuations in intraoral pressure

Pressure Requirements & Durations Loudness (Phrase) Stress (Syllable) Phonetic Intensity (Phone)

Volume Requirements Speech breathing differs from quiet respiration: Requires greater volumes Quiet (10-15% of VC) Conversational (25% of VC) Loud Speech (40% of VC) Differences achieved by the amount of air inhaled above resting volume

Volume Requirements 100 80-85% of VC 60-65% of VC 55% of VC 40 Resting Tidal Volume Conversational Tidal Volume Loud Tidal Volume

Frequency Requirements Breathing frequency- 10-20 times per minute Length of breath depends on length of utterance Grunting “Uh-huh” will take longer than quiet breathing Loud statement requires deep inspiration of air which we use past resting (forced expiration) Usually loud utterance not past 35% VC

Frequency Requirements 100 80% % VC Resting Volume Impassioned Plea 40 35% “UH HUH”

Duration Requirements Different between quiet & speech: How quickly we inhale Resting or heavy exercise- inhale= exhale Production of sound (whisper, argue, sing or converse)= quick inhalation & long, slow exhalation Speech: 10% of respiratory cycle (inhaling); 90% (exhaling) Duration during speech depends on: Breathy Loudness

Duration Requirements Inspiration Expiration 10% 90% % VC Resting Volume Loud Conversation Breathy

Respiratory Mechanics of Speech What adaptations to the respiratory system are made for speech? Control over: 1) Effects of changes in lung volume during the phrase 2) Active expiratory forces needed to maintain required alveolar pressure for the phrase

Relaxation Pressure & Lung Volume Deeper the inspiration = greater resistance of elastic lung tissue & air sacs against greater stretching & inflation Relaxation Pressure (Passive expiratory force) = Elastic recoil from inspiration, gravity & untorquing of rib cartilage when chest is raised

Relaxation Pressure & Lung Volume Louder & longer the phrase= Greater volume of air (volume & depth of inspiration increase) Inspiration increases= Passive resistance recoil increases= Greater relaxation pressure Elastic recoil are so strong that they exceed alveolar pressure for speech (above 60%)

Speech Pressures & Volumes % VC Tidal Volume Relaxation pressure Atmospheric pressure Alveolar Pressure for Speech Atmospheric pressure

Maintaining Alveolar Pressure for Speech Both inspiratory & expiratory muscles are used to begin to speak Some expiratory muscles are used during inspiration When you begin to speak: Relaxation pressures too high for the alveolar pressure Offset excessive relaxation pressure by inhalatory muscular contraction continuing to lift the rib cage until relaxation pressure was reduced to the necessary alveolar pressure

Respiratory Dynamics for Speech Relaxation Pressure Alveolar Pressure for Speech Atmospheric Pressure Expiratory Contraction Increases Active Inspiratory Checking of Relaxation Pressure Increases

Reading/Assignments Seikel: Pgs. 135-153 Dickson: Pgs. 85-87