Head and Neck Muscles

Orbicularis oculi

• a circular muscle that surrounds the eye

• It is responsible for closing the eyelids and protecting the eye from external stimuli

Orbicularis oris

• a circular muscle located around the mouth

• It is responsible for puckering and closing the lips, as well as controlling the movements of the mouth during speech and facial expressions

Buccinator

• a thin, flat muscle located in the cheeks

• It plays a crucial role in chewing and helps to compress the cheeks against the teeth, allowing for actions such as blowing, whistling, and sucking

Masseter

• a powerful muscle located in the jaw

• It is the primary muscle responsible for closing the jaw during chewing and biting

• It helps to elevate the mandible and is one of the strongest muscles in the human body

Temporalis

• a large muscle located on the side of the head, above the ear

• It is responsible for the movement of the jaw, including chewing and biting

• It works in conjunction with the masseter muscle to elevate and retract the mandible

Occipitalis

• located at the back of the head

• It works in conjunction with the frontalis muscle to move the scalp backward and raise the eyebrows

Frontalis

• located on the forehead and extends from the eyebrows to the hairline

• It is responsible for raising the eyebrows and wrinkling the forehead, allowing for various facial expressions such as surprise or concern

Mentalis

• a small muscle located on the chin

• It allows for various movements of the lower lip and chin, including protrusion and wrinkling

• It plays a role in facial expressions such as pouting or expressing doubt

Stylohyoid

• a slender muscle that runs from the styloid process of the temporal bone to the hyoid in the neck

• It helps in the movements of the hyoid bone during swallowing and speaking

Mylohyoid

• a flat, triangular muscle located in the floor of the mouth

• It forms the base of the oral cavity and assists in swallowing, elevating the hyoid bone, and controlling the position of the tongue

Sternohyoid

• a thin, strap-like muscle located in the neck

• It runs from the sternum to the hyoid bone and depresses the hyoid bone and larynx, aiding in actions such as swallowing and speaking

Thyrohyoid

• a small muscle located in the neck

• It connects the thyroid cartilage to the hyoid bone and helps in the movements of the larynx during swallowing and speaking

Sternocleidomastoid

• a large muscle located in the neck

• It runs diagonally from the sternum and clavicle to the mastoid process behind the ear

• It allows for the rotation and flexion of the head and neck and also assists in raising the sternum during deep inhalation

Platysma

• a thin, sheet-like muscle located in the neck and upper chest

• It covers the front of the neck and assists in various facial movements, such as lowering the jaw or pulling the corners of the mouth in expressions of sadness or tension