Muscle |
Origin |
Insertion |
Action |
1. Platysma
|
Fascia over deltoid and pectoralis major muscles. |
Mandible, blends with muscles around the angle of the mouth, and skin of the lower face. |
Draws outer part of lower lip inferiorly and posteriorly as in pouting; depresses mandible.
|
2. Mentalis |
Mandible.
|
The skin of the chin.
|
Elevates and protrudes lower lip and pulls skin of chin up, as in pouting. |
3. Orbicularis oris |
Muscle fibers that surround the opening of the mouth. |
The skin at the corner of the mouth.
|
Closes and protrudes lips, as in kissing; compresses lips against teeth; and shapes lips during speech. |
4. Corrugator supercilii
|
The medial end of the superciliary arch of the frontal bone. |
Skin of eyebrow.
|
Draws eyebrow inferiorly and wrinkles skin of forehead vertically as in frowning. |
5. Orbicularis oculi |
The medial wall of the orbit.
|
Circular path around an orbit. |
Closes eye. |
6. Occipitofrontalis (Frontal belly) |
Epicranial aponeurosis.
|
Skin superior to supraorbital margin.
|
Draws scalp anteriorly, raises eyebrows, and wrinkles forehead skin horizontally as in a look of surprise. |
Reference: Tortora & Derrickson. (2012). Chapter 11: The Muscular System. Principles of anatomy and physiology. (13th ed.).