Editing Tongue (section)

====Muscles====
The eight muscles of the human tongue are classified as either ''intrinsic'' or ''extrinsic''. The four intrinsic muscles act to change the shape of the tongue, and are not attached to any bone. The four extrinsic muscles act to change the position of the tongue, and are anchored to bone.

=====Extrinsic=====
[[File:Hyoglossus.png|thumb|right|220px|Lateral view of the tongue, with extrinsic muscles highlighted]]
The four extrinsic muscles originate from bone and extend to the tongue. They are the [[genioglossus]], the [[hyoglossus]] (often including the [[chondroglossus]]) the [[styloglossus]], and the [[palatoglossus]]. Their main functions are altering the tongue's position allowing for protrusion, retraction, and side-to-side movement.<ref name="GRAYS2005">{{cite book|title=Gray's anatomy for students|date=2005|publisher=Elsevier|isbn=978-0-8089-2306-0|location=Philadelphia, Pennsylvania |pages=989–995|first1=Richard L. | last1 = Drake | first2 = Wayne | last2 = Vogl | first3 = Adam W. M. | last3 = Mitchell}}</ref>

The genioglossus arises from the [[mandible]] and protrudes the tongue. It is also known as the tongue's "safety muscle" since it is the only muscle that propels the tongue forward.

The hyoglossus, arises from the [[hyoid bone]] and retracts and depresses the tongue. The chondroglossus is often included with this muscle.

The styloglossus arises from the [[Temporal styloid process|styloid process]] of the [[temporal bone]] and draws the sides of the tongue up to create a trough for swallowing.

The palatoglossus arises from the [[palatine aponeurosis]], and depresses the [[soft palate]], moves the ''palatoglossal fold'' towards the midline, and elevates the back of the tongue during swallowing.

=====Intrinsic=====
[[File:Gray1020.png|thumb|right|240px|Coronal section of tongue, showing intrinsic muscles]]
Four paired intrinsic muscles of the tongue originate and insert within the tongue, running along its length. They are the [[superior longitudinal muscle of tongue|superior longitudinal muscle]], the [[inferior longitudinal muscle]], the [[vertical muscle of tongue|vertical muscle]], and the [[transverse muscle of tongue|transverse muscle]]. These muscles alter the shape of the tongue by lengthening and shortening it, curling and uncurling its apex and edges as in [[tongue rolling]], and flattening and rounding its surface. This provides shape and helps facilitate speech, swallowing, and eating.<ref name=GRAYS2005 />

The superior longitudinal muscle runs along the upper surface of the tongue under the mucous membrane, and functions to shorten and curl the tongue upward. It originates near the [[epiglottis]], at the [[hyoid bone]], from the median fibrous septum.

The inferior longitudinal muscle lines the sides of the tongue, and is joined to the styloglossus muscle. It functions to shorten and curl the tongue downward.

The vertical muscle is located in the middle of the tongue, and joins the superior and inferior longitudinal muscles. It functions to flatten the tongue.

The transverse muscle divides the tongue at the middle, and is attached to the [[mucous membrane]]s that run along the sides. It functions to lengthen and narrow the tongue.