In general, what are
functions of the
muscles of the face,
neck & head?
The muscles of the head and neck perform many important tasks, including movement of the
head and neck, chewing and swallowing, speech, facial expressions, and movement of the eyes.
These diverse tasks require both strong, forceful movements and some of the fastest, finest, and
most delicate adjustments in the entire human body.
The muscles of the face are unique among groups of muscles in the body. While most muscles
connect to and move only bones, facial muscles mostly connect bones to skin.... These muscles,
including the zygomaticus major and orbicularis oris, pull on the skin to produce a seemingly
infinite number of facial expressions and to move the lips and cheeks during speech and eating.
Producing the body’s ability to close the mouth, bite, and chew food, the muscles of mastication
move the mandible relative to the rest of the skull. These muscles, including the masseter and
temporalis, elevate the jaw forcefully during chewing and gently during speech.
An extensive complement of tightly interlaced muscles allows the tongue a range of complex
movements for chewing and swallowing, as well as the important function of producing speech.
Of these, four extrinsic muscle sets (connecting the tongue to the surrounding bones) move the
tongue in virtually any direction, with fine shape changes (such as for speech) the province of the
four intrinsic tongue muscles.
As for the eye, six extrinsic eye muscles provide superior, inferior, lateral, and medial motion, as
well as rotation of the eyeball. These muscles produce extremely fine movements almost
constantly throughout the day with tremendous speed and accuracy. Located inside the eye, the
intrinsic eye muscles work tirelessly to dilate the pupils and focus the lens of the eye to produce
clear vision.
Even the middle ear takes part in the muscular system of the head and neck. In fact, the smallest
muscle of the skeleton is the stapedius, which measures around 1 millimeter (1/20th of an inch)
in length. The muscles of the middle ear contract to dampen the amplitude of vibrations from the
eardrum to the inner ear.
The neck muscles, including the sternocleidomastoid and the trapezius, are responsible for the
gross motor movement in the muscular system of the head and neck. They move the head in
every direction, pulling the skull and jaw towards the shoulders, spine, and scapula. Working in
pairs on the left and right sides of the body, these muscles control the flexion and extension of
the head and neck. Working individually, these muscles rotate the head or flex the neck laterally
to the left or right. Neck muscles contract to adjust the posture of the head throughout the course
of a day and have some of the greatest endurance of any muscles in the body.