Editing Pyramidal tracts (section)

==Function==
The nerves within the corticospinal tract are involved in [[Motor system|movement]] of [[muscle]]s of the body. Because of the crossing-over of fibres, muscles are supplied by the side of the brain opposite to that of the muscle.<ref name=GUYTONHALL2005 /> The nerves within the corticobulbar tract are involved in movement in muscles of the head. They are involved in swallowing, [[phonation]], and movements of the tongue.<ref name=YOUNG2007 /> By virtue of involvement with the [[facial nerve]], the corticobulbar tract is also responsible for transmitting [[facial expression]].<ref name=Arslan2001>{{cite book|last1=Arslan|first1=Orhan|title=Neuroanatomical Basis of Clinical Neurology|date=2001|publisher=CRC Press|isbn=1439806136|page=368|url=https://books.google.com/books?id=x3Gmj9_m1D0C&q=corticobulbar&pg=PA368|url-status=live|archive-url=https://web.archive.org/web/20180503163021/https://books.google.com/books?id=x3Gmj9_m1D0C&pg=PA368&dq=corticobulbar#v=onepage&q=corticobulbar&f=false|archive-date=2018-05-03}}</ref> With the exception of lower muscles of facial expression, all functions of the corticobulbar tract involve inputs from both sides of the brain.<ref name=Arslan2001 />

The [[extrapyramidal system]] refers to tracts within the spinal cord involved in involuntary movement but not part of the pyramidal tracts.<ref name=GUYTONHALL2005 /> Their functions include the control of posture and [[muscle tone]].{{citation needed|date=June 2014}}