Anatomy of the Tongue

Tongue

• Thick, vascular, and voluntary muscle surrounded by a mucous membrane, anchored to the floor of the mouth by the lingual frenulum.
• Consists of symmetric halves divided by the median septum, with a deep tendinous band located within the midline.

Intrinsic Tongue Muscles

• 4 pairs of muscles:
  • Superior longitudinal muscle: most superficial, runs obliquely and longitudinally from base to apex, changes the shape of the tongue by shortening and thickening it.
  • Inferior longitudinal muscle: close to the ventral surface, runs longitudinally from base to apex, changes the shape of the tongue by shortening and thickening it.
  • Transverse muscle: deep to the superior longitudinal muscle, runs transversely from the median septum toward the lateral surface.
  • Vertical muscle: runs vertically from the dorsal surface to the ventral surface in the body.

Extrinsic Tongue Muscles

• 4 muscles:
  • Palatoglossus: forms the anterior faucial pillar in the oral cavity, elevates the base of the tongue, and depresses the soft palate.
  • Styloglossus: retracts the tongue, moving it superiorly and posteriorly.
  • Genioglossus: protrudes the tongue, depresses parts of the tongue surface.
  • Hyoglossus: depresses the tongue.

Muscles of the Pharynx

• Involved in speaking, swallowing, and middle ear function.
• Part of both respiratory and digestive tracts, connected to both the nasal and oral cavities.

Muscles of the Pharynx (continued)

• Stylopharyngeus muscle: paired longitudinal muscle, elevates and widens the pharynx.
• Pharyngeal constrictor muscles: 3 pairs (superior, middle, inferior), raise the pharynx and larynx, and help drive food inferiorly into the esophagus during swallowing.
• Superior pharyngeal constrictor muscle: originates from the hamulus of the medial pterygoid plate, mandible, and pterygomandibular raphe, and inserts into the pharyngeal raphe.
• Middle pharyngeal constrictor muscle: originates from the hyoid bone and stylohyoid ligament, inserts into the pharyngeal raphe.
• Inferior pharyngeal constrictor muscle: originates from the thyroid and cricoid cartilage, inserts into the pharyngeal raphe.

Muscles of the Soft Palate

• 5 pairs of muscles, all involved in speaking and swallowing.
• Soft palate forms the non-bony posterior part of the roof of the mouth or the oropharynx and connects laterally with the tongue.
• All muscles except the tensor veli palatini are innervated by CN X (pharyngeal plexus).
• Tensor veli palatini: innervated by the medial pterygoid nerve.
• Palatopharyngeus muscle: moves the palate posteroinferiorly and the posterior pharyngeal wall anterosuperiorly to help close off the nasopharynx (tenses soft palate).
• Levator Veli Palatini Muscle: raises the soft palate and helps bring it closer to the nasal cavity.

Explore the structure and function of the tongue, including its muscles, mucous membrane, and median septum. Learn about the intrinsic tongue muscles and their roles.