Name the muscle that may cause the following facial expression and write down its origin, insertion, and action.
|
Facial expression |
Muscle responsible |
Origin |
Insertion |
Action |
|
1. |
Platysma |
Subcutaneous tissue of infraclavicular and supraclavicular regions |
Base of mandible; skin of cheek and lower lip; angle of mouth (modiolus); orbicularis oris |
Depresses mandible (against resistance); tenses skin of interior face and neck (conveying tension and stress) |
|
2.
|
Mentalis |
Body of mandible (anterior to roots of inferior incisors) |
Skin of chin (mentolabial sulcus) |
Elevates and protrudes lower lip; elevates skin of chin (showing doubt) |
|
3.
|
Orbicularis oris (oral sphincter) |
Medial maxilla and mandible; deep surface of perioral skin; angle of mouth (modiolus) |
Mucous membrane of lips |
Tonus closes oral fissure; phasic contraction compresses and protrudes lips (kissing) or resists distension (when blowing) |
|
4.
|
Corrugator supercilii |
Medial end of superciliary arch |
Skin superior to middle of supraorbital margin and superciliary arch |
Draws eyebrow medially and inferiorly, creating vertical wrinkles above nose (demonstrating concern or worry) |
|
5.
|
Orbicularis oculi |
Medial orbital margin; medial palpebral ligament; lacrimal bone |
Skin around margin of orbit; superior and inferior tarsal plates |
Closes eyelids: palpebral part does so gently; orbital part tightly (winking) |
|
6.
|
Occipitofrontalis |
|
|
|
|
Epicranial aponeurosis |
Skin and subcutaneous tissue of eyebrows and forehead |
Elevates eyebrows and wrinkles skin of forehead; protracts scalp (indicating surprise or curiosity) |
|
|
Lateral two-thirds of superior nuchal line |
Epicranial aponeurosis |
Retracts scalp; increasing effectiveness of frontal belly |