The tongue functions as a primary articulator in speech, shaping sounds through precise movements facilitated by its intricate muscle structure.
The tongue's role in speech production is crucial. It acts as a highly versatile and mobile organ within the vocal tract, capable of assuming a vast array of shapes and positions. This adaptability is essential for producing the diverse range of sounds that make up human language. This control comes from two sets of muscles: extrinsic and intrinsic.
Extrinsic Muscles
These muscles connect the tongue to structures outside of it, like the hyoid bone, mandible (jaw), and skull base. Their main function is to position the tongue within the mouth.
- Genioglossus: Protrudes the tongue and depresses its center.
- Hyoglossus: Depresses and retracts the tongue.
- Styloglossus: Elevates and retracts the tongue.
- Palatoglossus: Elevates the back of the tongue.
Intrinsic Muscles
These muscles are located entirely within the tongue and are responsible for changing its shape.
- Superior Longitudinal: Elevates the tongue tip and retracts the tongue.
- Inferior Longitudinal: Depresses the tongue tip and retracts the tongue.
- Transverse: Narrows and elongates the tongue.
- Verticalis: Flattens and widens the tongue.
Tongue's Articulatory Functions
The tongue's position and shape are key to creating various speech sounds, including:
- Vowels: The height of the tongue (high, mid, low) and its front-back position in the mouth (front, central, back) largely define vowel sounds.
- Consonants: The tongue is involved in the production of many consonants, creating constrictions or closures at different points in the mouth. Examples include:
- Alveolar sounds: Sounds like /t/, /d/, /n/, and /s/ where the tongue makes contact with the alveolar ridge (the area behind the upper teeth).
- Palatal sounds: Sounds like /ʃ/ (sh) and /ʒ/ (zh) where the tongue approaches the hard palate.
- Velar sounds: Sounds like /k/ and /ɡ/ where the back of the tongue makes contact with the soft palate (velum).
- Interdental sounds: Sounds like /θ/ (th in "thin") and /ð/ (th in "this") where the tongue is placed between the teeth.
- Diphthongs: During the production of diphthongs, the tongue moves from one position to another within a single syllable.
In summary, the tongue is an essential component of the organ of speech, actively shaping the vocal tract to produce a wide range of sounds through the coordinated action of its extrinsic and intrinsic muscles. Without the tongue's precise control and flexibility, intelligible speech would be impossible.
