344 week 10

Onward to Cavities of the Vocal Tract

Cavities of the Vocal Tract

  • The vocal tract consists of several key cavities that play significant roles in speech production and resonance. These cavities include:

    • Oral Cavity

    • Buccal Cavity

    • Pharyngeal Cavity

    • Nasal Cavity

    • Pharyngeal Tonsil (Adenoids)

    • Orifice of the Eustachian Tube

    • Oropharynx

    • Laryngopharynx

    • Nasopharynx

    • Velum

Detailed Description of Vocal Tract Cavities

Oral Cavity

  • Definition: The oral cavity extends from the oral opening (mouth) at the front to the faucial pillars at the back.

  • Components:

    • Hard Palate:

    • Composed of rugae (folds) and the median raphe (a seam).

    • Soft Palate and Uvula:

    • The muscular extension of the hard palate in front of the palatine bone.

    • Faucial Pillars:

    • Function to trigger the swallow reflex; muscles elevate the tongue and pharynx.

    • Palatine Tonsils:

    • Masses of lymphoid tissue located in the oral cavity.

Buccal Cavity

  • Definition: The buccal cavity refers to the space between the teeth and cheeks.

  • Boundaries:

    • Lateral: Cheeks

    • Anterior: Lips

    • Medial: Teeth

    • Posterior Margin: At the third molar.

  • Functions:

    • Plays a role in speech resonance and swallowing.

Nasal Cavity

  • Anatomical Features:

    • Two chambers divided by the nasal septum.

    • Composition of Nasal Septum:

    • Made up of the vomer bone, parts of the ethmoid bone, and cartilage.

    • Borders:

    • Superior: Nasal bones and ethmoid bone internally

    • Lateral: Frontal process of the maxillae

    • Inferior: Hard palate formed by the paired palatine processes of the maxillae and palatine bones.

  • Nasal Conchae:

    • Function to increase surface area to create turbulent airflow.

Pharyngeal Cavity

  • Definition: Extends from the vocal folds (below) to the region behind the nasal cavities (above).

Subdivisions of the Pharyngeal Cavity

  • Nasopharynx:

    • Located above the soft palate.

    • Anteriorly bounded by the posterior opening of the nasal cavity.

    • Contains the Eustachian tube.

  • Oropharynx:

    • Located behind the oral cavity, bounded above by the velum.

    • Lower boundary is marked by the hyoid bone, which is the upper boundary of the laryngopharynx.

  • Laryngopharynx (Hypopharynx):

    • Anteriorly bounded by the epiglottis.

    • Inferiorly bounded by the esophagus.

Schematic Understanding of the Pharyngeal Cavity

  • Factors Influencing Layout:

    • Relationships with surrounding structures such as the nasopharynx, oropharynx, laryngopharynx, larynx, esophagus, trachea, and oral cavity.

  • dysarthria is the impairment for speech, slurred speech

  • another motor speech deficit is apraxia of speech: motor planning

  • aphasia is a language impairment