Recording-2025-04-15T19:57:21.624Z

Lungs and Breathing

• Function of Lungs:

  • Create an airstream that vibrates the vocal folds through the larynx.
  • Vital for gas exchange, primarily oxygenating the blood.

• Inhalation (Inspiratory Phase):

  • For lungs to inflate, pressure inside them must be less than atmospheric pressure.
  • Achieved by diaphragm contraction (pulling down) and interaction with rib muscles which enlarge the thoracic cavity.

• Exhalation:

  • Initially involves a quick inhalation followed by a longer exhalation when speaking.
  • Inhale approximately 1,000 cc of air when engaged in speech breathing compared to around 100 cc during restful breathing.
  • Use of abdominal muscles to control airflow and pressure vital for speech production.

Speech Breathing and Phonation

• Phonation:

  • The production of voice; requires air to flow through the larynx, utilizing the vibration of the vocal folds.

• Laryngeal Functions:

  • Biological Function: Protects the airway (e.g., prevents food/water from entering lungs).
  • Reflex actions such as coughing help to protect the airway.

• Vocal Folds:

  • Composed mostly of cartilage and muscle; they can be adducted (closed) or abducted (open).
  • Mnemonic Aid:
  • Adducted = ADD (together)
  • Abducted = Abduction (apart).

• Sound Production:

  • Airflow causes the vocal folds to vibrate, creating sounds.
  • Pitch changes based on the length of vocal folds: longer = higher pitch, shorter = lower pitch.

Frequency and Sounds

• Frequency of Vibration:

  • Measured in Hertz (Hz); e.g., 60 Hz for low sounds up to 3000 Hz for higher-pitched sounds.
  • Voiced sounds (like vowels) engage vocal fold vibration, while voiceless (like /s/) do not.

• Control of Vocal Folds:

  • Ability to change tension influences the amount of air pressure needed for vibration.
  • Tense vocal folds require more air to vibrate compared