Notes
Muscles of the Scalp, Eyes, & Nose
Nasalis:
- Originates on the maxilla and inserts on the nasal cartilage at the midline; it flares the nostrils.
Corrugator supercilii muscles:
- Originates on the frontal bone (specifically, from the medial supraorbital margin) and insert on the medial half of the eyebrows and laterally on the supraorbital margin on the frontal bone; they depress the eyebrows (and pull them medially).
Orbicularis oculi:
- Originates on the medial margin of the orbit (specifically, from the maxillary, frontal, and lacrimal bones), and inserts into the rim and skin of the orbit and eyelids; it moves the eyelids and surrounding skin to squint and close the eyes.
Frontalis:
- Originates on the frontal bone and skin of the eyebrows, and inserts into the galea aponeurotica (aka, the epicranial aponeurosis); it elevates the eyebrows, which wrinkles the forehead horizontally.
Additional Information:
- Cranial nerve VII (the facial nerve) innervates these muscles.
- Bell's palsy occurs when CN VII is damaged; Belly's palsy results in asymmetrical paralysis of the muscles of facial expression.