Original Editor - Venus Pagare
Musculus splenius capitis is one of the deep (or intrinsic) muscles of the back. It is a broad strap-like muscle in the back of the neck. Deep to Sternocleidomastoid at the mastoid process.
Dorsal ramus of spinal nerves C3-C6
Muscular branches of the occipital artery from the external carotid artery. 
Acting bilaterally: extension of the head and cervical spine
Acting unilaterally: lateral flexion of the head and neck and rotation the head to the same side. 
It also assists in supporting the head in the erect position
Effective management of neck pain should include exercises that focus on activating Semispinalis Cervicis as well as stretching and myofascial release of the splenius capitis .
- Gray's Anatomy of Human Body, Bartleby.com edition. New York: 2000.fckLRhttp://www.bartleby.com/107/115.html
- Wheeless`textbook of orthopedic, splenius capitis , available from:http://www.wheelessonline.com/ortho/splenius_capitis (24july 2019 )
- J Schomacher, J Erlenwein, A Dieterich, F Petzke, F Petzkeb, D Falla. Can neck exercises enhance the activation of the semispinalis cervicis relative to the splenius capitis at specific spinal levels? Manual therapy, October 2015:20: 694-702.