The occipitalis is a muscle located at the back of the head. It is part of the epicranius muscle group, which covers the top and back of the skull. The primary function of the occipitalis is to help move the scalp backward, contributing to facial expressions and overall head movement. This muscle works in conjunction with the frontalis, which is located at the front of the head. Together, they form the galea aponeurotica, a fibrous tissue that connects them. The occipitalis plays a role in various activities, such as raising the eyebrows and expressing surprise.