PMC

Muscles of the human tongue. (A) The superior longitudinal (SL) muscle spans the length of the tongue just beneath the mucosa of its superior surface, it is believed to shorten the tongue and curve the tip superiorly. The SL is the only unpaired muscle of the tongue. (B) The inferior longitudinal (IL) muscles span the length of the tongue just above the mucosa of its inferior surface, they are believed to shorten the tongue and curve the tip inferiorly. (C) The transverse and vertical (T/V) muscle group. Transverse muscles connect the medial septum to the lateral aspect of the tongue; they are believed to narrow the tongue. The vertical muscles connect the inferior surface to the superior surface; they are believed to flatten the tongue. (D) The hyoglossus (HG) muscles originate from the hyoid bone and also insert into the inferior-lateral margins of the tongue, they are believed to cause tongue retraction and depression. (E) The styloglossus (SG) muscles originate from the styloid processes and insert along the inferior-lateral margins of the tongue, they are believed to cause tongue retraction and elevation. (F) The genioglossus (GG) muscles are midline muscles which originate from the posterior surface of the mandible. The GG muscles are believed to cause tongue protrusion with a secondary effect of drawing the midline of the tongue inferiorly, such as seen in the tongue on the right in . As mentioned in the legend for the muscles are all rendered as separate objects for the sake of clarity, but in reality there is extensive overlap. One example is that the GG muscle becomes the vertical muscle in the medial third of the tongue. Therefore, the GG muscle actually passes between sheets of the transverse muscle and then between SL fascicles to insert into the dorsal surface of the tongue. The other example is that the T/V muscles are rendered as a single object.

Muscles of the human tongue. (A) The superior longitudinal (SL) muscle is the only unpaired muscle of the tongue which spans the length of the tongue just beneath the mucosa of its superior surface. (B) The inferior longitudinal (IL) muscle spans the length of the tongue just above the mucosa of its inferior surface. (C) The transverse and vertical (T/V) muscles. The T muscle connects the medial septum to the lateral aspect of the tongue. The V muscle connects the inferior surface to the superior surface. (D) The genioglossus (GG) muscle is midline muscle which originates from the posterior surface of the mandible. (E) The styloglossus (SG) muscle originates from the styloid processes and insert along the inferior-lateral margins of the tongue. (F) The hyoglossus (HG) muscle originates from the hyoid bone and also insert into the inferior-lateral margins of the tongue. The muscles are all rendered as separate objects for the sake of clarity, but in reality there is extensive overlap. One example is that the GG muscle becomes the vertical muscle in the medial third of the tongue. The other example is that the T/V muscles are rendered as a single object.

Gray-scale sonographic images of the normal oral tongue (A–C). Normal muscle striations can be seen in the paramedian oral tongue (A, sagittal) and in the midline dorsum of the tongue (B, transverse). Note that in the midline, the median fibrous septum is discernable as an echogenic line (arrow in B). At the lateral edge of the oral tongue, the parenchyma is mildly heterogeneous and hyperechoic (C, sagittal). D, Doppler sonography image of the lateral oral tongue shows fairly even distribution of blood flow throughout the parenchyma.

Tongue anatomy. (A) Drawing of the adult tongue showing the branchial arch (BA) derivation of the nerve supply of its mucosa. The anterior two-thirds are known as the oral part of the tongue, whereas the posterior third is called the pharyngeal part. (B) Drawing of a coronal section of the adult tongue with intrinsic and extrinsic muscles indicated. The CNCC-derived lingual septum is depicted. Abbreviations: 1st, first BA; 3rd, third BA; 4th, fourth BA.