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.
These include the buccinator, masseter, temporalis and pterygoid muscles. Below the muscles of your face are neck muscles that help support and move your head. These include the sternocleidomastoid muscles, which flex your neck, move your head from shoulder to shoulder and turn your face from side to side. Moving around to the back, we have axial muscles of the spinal column.