AAU28D: Set Reading 2- How does the larynx work to produce voice?

Crannell (2000) mentions that a voice is produced by the means of a vibrating agent. In the production of sound, we found that sound is in fact made by the combination of air passing through the vocal folds within the larynx. The vocal folds vibrate from the moving air and create sound waves that reverberate through the larynx and up towards the pharynx, nose and mouth.

We all know that sound travels the fastest through a solid because neighbouring atoms are closely packed in an orderly manner and form what we call a crystal lattice structure. A larynx is made of cartilage surrounded by fibrous tissue like the thickening and stretching muscles and contains the posterior cricoarytenoid, the transverse and oblique arytenoids, the thyroarytenoids and vocalis, and lastly the cricothyroid. Being physically linked side by side to each other, all these parts will thus receive the vibrations from the vocal folds, manipulate the vibrations and produce a variety of sounds.

Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. (2003). Larynx photo.

How do these parts manipulate sound? The posterior cricoarytenoid that widens during inhalation and narrows during exhalation gives us the ability to whisper. The transverse and oblique arytenoids open and close the vocal folds so that we may produce phonation. The thyroarytenoids and vocalis will loosen the vocal folds and allow us to talk at a lower pitch during exhalation. The cricothyroid does the reverse by stretching out the vocal folds with help from the stretching muscles and increase the pitch of our voice. The thickening muscles shorten and thicken the vocal folds so that the vibrations are suppressed, allowing us to produce low notes. Altogether, the larynx acts as a sum of all the different parts and is adequately known as the voice box.

Crannell, K.C. (2000). Voice and Articulation (4^th ed.). Belmont, CA: Wadsworth/Thomson Learning, pp. 35–42.

Larynx. (n.d.) Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. (2003). Retrieved 2018, November 13 from https://medical-dictionary.thefreedictionary.com/larynx