The muscles surrounding the tongue on its underside have complex connections with the muscles of the floor of the mouth, soft palate, pharynx and other organs of the upper digestive tract. Largely due to this, the asymmetrical movement of the tongue in the horizontal plane is necessary for the participation of many muscles in the articulation of sounds of different pitches. These include the styloglossus muscle (mm. pterygoidei), the glossopharyngeal tract (vf. facious vagus) and the hypoglossal tract (vf. thyreo pharyngeus).
The muscle tissue of the tongue itself consists of superficial and deep muscle bundles. Deep bundles are the main muscles of the tongue, or the root of the tongue. The tendons of the main muscles are located at a depth of up to 25 mm. Its lateral parts are a continuation of the lateral wall of the pharynx, and from below they are parallel to the epiglottis.
The transverse muscle of the tongue (lat. Musculus transversus lingualis profundus) is the deepest muscle of the intrathick and the posterior deepest muscle of the root of the tongue. When contracting, it greatly stretches the side walls, making the mouth opening more open. It is a continuation of the chin muscle of the same name.
Contraction of the superficial muscle of the tongue produces a projection at its tip which forms the laryngeal tube when the tongue is opened, and thickens the projecting lateral edge of this muscular thickening in the same area if it is contracted, giving it a “V” shape.