Articulation: Pharynx and Mouth
In the previous chapters, we saw how the current of air generated by the respiratory system could be transformed at the level of the larynx by various adjustments of the vocal folds. It is at the level of the supralaryngeal cavities that the articulatory organs give speech sounds their characteristics and definitive properties.
All the organs that have a role in this final stage of speech production have a primarily biological function: they enable the absorption, mastication and transport of food. Their utilization for speech is a secondary function. The property common to all these organs is their great mobility and thus the possibilities they offer for rapid modification of the vocal tract: changing the size of the oral cavity and the pharyngeal cavity, connecting with the nasal cavity, adding a labial resonance. The articulators act either by allowing air to pass relatively freely (vowel articulation) or, through a mesh of constrictions, creating phenomena of turbulence and frictional sounds (consonantal articulation). Finally, consonantal articulation can also be created when the articulators completely block the passage of air, as for plosives.
The bucco-pharyngeal cavity lies at the top of the larynx and extends to the lips (see Figure 3.1). It is bounded on top by the palatal bone, at the back by the pharyngeal wall and at the bottom by the jaw and the hyoid bone. We will examine in turn the articulatory roles of the different structures and organs of the oral cavity and the pharynx.