Corpus: Procerus muscle
from Latin: procerus - slender, tall
1. Definition
The procerus muscle is a small muscle located in the glabella region, part of the mimic musculature.
Some sources consider it not an independent muscle but rather a division of the occipitofrontalis muscle.
2. Course
The procerus muscle originates from the fascia above the base of the nasal bones. Its fibers run steeply upward, inserting into the skin of the glabella. Some fibers intermix with those of the frontal belly of the occipitofrontalis muscle.
3. Innervation
The procerus muscle is innervated by the temporal branches of the facial nerve (cranial nerve VII).
4. Function
The procerus muscle pulls the skin of the forehead and the medial area of the eyebrows downward. Like other muscles in the facial expression group, it is closely attached to the underlying skin, causing the skin to move with the muscle. Along with the depressor supercilii muscle, it creates a horizontal fold between the root of the nose and the glabella, commonly known as the frown line.