Final answer:
The head is moved and rotated by the axial muscles of the neck, with the sternocleidomastoid being a major muscle for lateral flexion and rotation. Other muscles like the infrahyoid group help in swallowing and speech, and posterior neck muscles manage head extension. These muscles work together to provide stability and flexibility to the head and neck region.
Step-by-step explanation:
Muscles That Move the Head
The muscles that enable the movement of the head are primarily axial muscles of the neck, including both superficial and deeper layers. One of the major muscles involved is the sternocleidomastoid, which is responsible for the lateral flexion and rotation of the head. When this muscle acts on one side, it causes the head to rotate; when it contracts on both sides, it brings about the flexion of the head. Additionally, the sternocleidomastoid muscle divides the neck into anterior and posterior triangles, which can be identified when observing the neck from the side.
Apart from the sternocleidomastoid, there are other muscles such as the infrahyoid group that include the omohyoid, sternohyoid, and thyrohyoid, which are associated with depressing the hyoid bone and influencing voice by positioning the larynx. The posterior neck muscles primarily manage the extension of the head. These collective efforts of various muscles support head movements, stabilize the hyoid bone, and are integral for actions such as swallowing and speaking.
All muscles of the head and neck are considered axial muscles, with some like the muscles of facial expression integrating with the skin rather than bone, which allows for facial movements. Moreover, this complex muscle structure ensures the stability and movement of the head and shoulders, adhering to their crucial roles in both posture and mobility.