Item 1:
muscle: platysma
origin: fascia over deltoid and pectoralis major
insertion: mandible, blends with muscles around angle of mouth, and skin of lower face
action: draws outer part of lower lip inferiorly and posteriorly as in pouting; depresses mandible
Item 2
muscle: mentalis
origin: mandible
insertion: skin of chin
action: elevates and protrudes lower lip and pulls skin of chin up, as in pouting
Item 3
muscle: orbicularis oris
origin: muscle fibers surrounding opening of mouth
insertion: skin at corner of mouth
action: closes and protrudes lips, as in kissing; compresses lips against teeth; and shapes lips during speech
Item 4
muscle: corrugator supercilii
origin: medial end of superciliary arch of frontal bone
insertion: skin of eyebrow
action: draws eyebrow inferiorly and wrinkles skin of forehead vertically as in frowning
Item 5
muscle: orbicularis oculi
origin: medial wall of orbit
insertion: circular path around orbit
action: responsible for eye closure
Item 6
muscle: frontal belly
origin: Epicranial aponeurosis
insertion: Skin superior to supraorbital margin
action: draws scalp anteriorly, raises eyebrows, and wrinkles skin of forehead horizontally as in look of surprise
Reference:
Tortora, G. J., & Derrickson, B. (2017). Principles of anatomy and physiology (15th ed.). Wiley Custom Learning Solutions. https://handoutset.com/wp-content/uploads/2022/05/Principles-of-anatomy-and-physiology-Wiley-2017-Derrickson-Bryan-H._-Tortora-Gerard-J..pdf