Respiratory Muscles:
* Diaphragm: This dome-shaped muscle contracts to expand the chest cavity and draw air into the lungs.
* Intercostal Muscles: These muscles between the ribs help further expand and contract the chest cavity.
* Abdominal Muscles: These muscles assist in exhaling by pushing air out of the lungs.
Vocal Muscles:
* Vocal Cords: These folds of tissue in the larynx (voice box) vibrate as air passes over them, producing sound.
* Muscles of the Larynx: These muscles control the tension and position of the vocal cords, influencing pitch and volume.
Articulation Muscles:
* Tongue: The tongue is a highly flexible muscle that moves to shape the sounds of speech.
* Lips: The lips help form different sounds by opening, closing, and rounding.
* Cheeks: The cheeks assist in shaping the mouth and creating air pressure for certain sounds.
* Soft Palate: The soft palate rises to block the nasal cavity for certain sounds, preventing air from escaping through the nose.
* Jaw: The jaw muscles move the lower jaw to open and close the mouth, allowing air to pass through the vocal tract.
Other Muscles:
* Muscles of the face: These muscles help with facial expressions, which can subtly influence speech.
* Muscles of the neck: These muscles support the head and neck, ensuring stable positioning for speech.
It's important to note that the specific muscles used will vary depending on the word being spoken and the individual's speaking style. The brain controls all these muscles in a highly coordinated fashion to produce speech.