Epicranius is a term used to describe the muscle that covers the top of the head and connects with the muscles of the forehead. There are several synonyms that can be used to describe this muscle, including occipitofrontalis, frontalis muscle, and occipitalis muscle. The occipitofrontalis muscle is a thick, flat muscle that covers the top of the head and is also responsible for raising the eyebrows and wrinkling the forehead. The frontalis muscle is located in the forehead and raises the eyebrows, while the occipitalis muscle is located at the back of the head and is responsible for pulling the scalp back. Regardless of their differences, all of these muscles work in harmony to enable us to display a range of facial expressions.