Corpus: Corrugator supercilii muscle

The corrugator supercilii muscle is a small, pyramid-shaped muscle located near the palpebral fissure, and is part of the facial expression muscles.

The corrugator supercilii muscle originates from the superciliary arch (arcus superciliaris) of the frontal bone. Its fibers run obliquely upward and laterally beneath the occipitofrontalis muscle and partly beneath the orbicularis oculi muscle. The fibers insert into the skin of the lateral eyebrow.

The corrugator supercilii muscle is innervated by the temporal branches of the facial nerve (cranial nerve VII).

The corrugator supercilii muscle draws the eyebrow medially and downward. This action causes the overlying skin to follow the muscle, creating vertical wrinkles between the eyebrows, commonly known as frown lines or glabellar lines. The muscle also contributes to expressions that convey a "suffering" or concerned appearance.