Corrugator supercilii muscle

The corrugator supercilii is a small, narrow, pyramidal muscle close to the eye.
It is located at the medial end of the eyebrow, beneath the frontalis and just above orbicularis oculi muscle.
It arises from the medial end of the superciliary arch; and its fibers pass upward and laterally, between the palpebral and orbital portions of the orbicularis oculi muscle, and are inserted into the deep surface of the skin, above the middle of the orbital arch.
The name "corrugator supercilii" is Latin, meaning "wrinkler of the eyebrows".
Action.
The corrugator draws the eyebrow downward and medially, producing the vertical wrinkles of the forehead. It is the "frowning" muscle, and may be regarded as the principal muscle in the expression of suffering. It also contracts to prevent high sun glare, pulling the eyebrows toward the bridge of the nose, making a roof over the area above the middle corner of the eye and typical forehead furrows.
The muscle is sometimes surgically severed or paralysed with botulinum toxin as a preventive treatment for some types of migraine or for aesthetic reasons.