Â© 2000 John Wiley & Sons, Inc. An inverse relationship between household income and violence exposure in youth hasbeen reported in numerous studies (e.g., Garbarino & Crouter, 1978; Gelles, 1992; Gelles& Straus, 1979; Steinberg, Catalano, & Dooley, 1981).
The head, attached to the top of the vertebral column, is balanced, moved, and rotated by the neck muscles (). When these muscles act unilaterally, the head rotates. When they contract bilaterally, the head flexes or extends. The major muscle that laterally flexes and rotates the head is the sternocleidomastoid.
Splenius Capitis Muscle. The splenius capitis muscle is a broad, strap like muscle located in the back of the neck. It connects the base of the skull to the vertebrae in the neck and upper thorax. When one muscle acts singly, it causes the head to rotate and bend toward one side; together, these muscles bring the head into an upright position. Anatomy Explorer.