The epicranial muscle, also called the epicranius, consists of two sections and covers the forehead, top, and upper-rear portion of the skull.
The frontalis section controls movement of the forehead and eyebrows, thus enabling forehead wrinkling. The occipitalis controls backward movement of the scalp, which raises the eyebrows. The occipitalis and frontalis sections of the epicranial muscle coordinate movement with the help of a tendon that connects them.
The frontalis section of the epicranial muscle is connected to the fascia (connective tissue) of the facial muscles and facial skin above the nose and eyes. The occipitalis section of the epicranial is attached to the occipital bone at the base of the skull and the temporal bones, which are located on both sides of the skull.
Blunt trauma or other damage to the epicranial muscle can cause facial paralysis, impacting the ability to move the eyebrows and forehead. A sudden onset of facial paralysis requires a medical diagnosis because facial paralysis can be caused by underlying disease or injuries that affect both the epicranial muscle and related nerves.