The occipitofrontalis muscle (also known as the epicranius muscle) is a facial muscle of the calvaria region consisting of occipital belly and frontal belly, which are connected to each other by the epicranial aponeurosis.

Occipital belly (Occipitalis muscle)

Origin: superior nuchal line (occipital bone).

Insertion: epicranial aponeurosis.

Action: moves the scalp posteriorly.

Innervation: posterior auricular nerve, a branch of the facial nerve (CN VII).

Blood supply: branches of the posterior auricular artery and occipital artery.

Frontal belly (Frontalis muscle)

Origin: epicranial aponeurosis.

Insertion: skin of the eyebrow.

Action: lifts the eyebrow and the upper eyelid, thus producing horizontal wrinkles of the forehead. Contractions of the muscle produce the facial expression of astonishment.

Innervation: temporal branch of the facial nerve (CN VII).

Blood supply: branches of the superficial temporal artery and ophthalmic artery.