1. Platysma
a. Origin: Fascia over deltoid and pectoralis major muscles.
b. Insertion: Mandible, blends with muscles around the angle of the mouth and the skin of the lower face.
c. Action: Draws the outer part of the lower lip inferiorly and posteriorly, as in pouting; depresses the mandible.
2. Mentalis
a. Origin: Mandible
b. Insertion: Skin of chin
c. Action: Elevates and protrudes lower lip and pulls the skin of chin up
3. Orbicularis oris
a. Origin: Muscle fibers surrounding the opening of the mouth
b. Insertion: Skin at the corner of the mouth
c. Action: Closes and protrudes lips, as in kissing; compresses lips against teeth and shapes lips during speech
4. Corrugator supercilii
a. Origin: Medial end of superciliary arch of the frontal bone
b. Insertion: Skin of eyebrow
c. Action: Draws eyebrow inferiorly and wrinkles skin of the forehead vertically as in frowning
5. Orbicularis oculi
a. Origin: Medial wall of the orbit
b. Insertion: Circular path around the orbit
c. Action: Closes eye.
6. Occipitofrontalis
a. Origin: Occipital belly (occipital bone) and frontal belly (epicranial aponeurosis)
b. Insertion: Skin superior to supraorbital margin
c. Action: Draws scalp anteriorly, raises eyebrows, and wrinkles skin of forehead horizontally as in the look of surprise.