Communication Sciences and Disorders 4411A/B Lecture Notes - Lecture 3: Rib Cage, Vocal Folds, Phonation

• School: Western University
• Department: Communication Sciences and Disorders
• Course: Communication Sciences and Disorders 4411A/B
• Professor: Ivan Culum

Document Summary

Laryngeal system: respiratory system, articulatory system, resonance. Respiratory system: breathing, allows exchange of gases to sustain life, o2 in, co2 out. 14-16 inspiration-expiration cycles per minute: speech 10% inhalation, 90% exhalation. Inhalation: active process, diaphragm contracts (moves down, rib cage expands (up and out, negative pressure created relative to outside air, air rushes in through mouth or nose (or both) to equalize air pressure. Lung volume increases: exhalation, generally, a passive process, diaphragm relaxes, chest wall returns to resting state, positive pressure relative to outside air, air rushes out. Lungs decrease in size: active (forced) exhalation, contraction of abdominal and ribcage muscles. Faster rate of vibration higher pitch: slower rate of vibration lower pitch, size and mass of vocal folds, anatomical, smaller higher pitch. Larger lower pitch: contraction of laryngeal muscles. Lengthened and tensed vocal folds higher pitch: relaxed and shortened vocal folds lower pitch. Loudness determined by changes in subglottal air pressure amplitude vs. intensity.