The facial expression is created by a complex interaction of different facial muscles/muscle groups, which are harmoniously coordinated with each other. A facial expression is therefore never created only by the contraction of one muscle, but by a "concert of different muscles". Each muscle has its own "vector", i.e. its own traction direction, contractile ability (strength of muscle shortening), muscle amplitude (shortening path), and its influence on the facial skin as an overlying layer.
The visible movements of the facial surface are called facial expressions. In most cases, an overall impression is created from individual mimic facets, as the individual movements of the facial muscles take place in fractions of a second. Facial expression is a part of the expressive behavior of humans as well as animals capable of it. In humans, together with other behaviors and actions such as gestures, it is an important component of non-verbal communication.
Facial expression is essentially based on the contraction of the mimic muscles and is produced particularly by the eyes and mouth as the most mobile parts of the face. There are about three thousand variations.
Our friends from ANATOMYNEXT support this site with their excellent 2D and 3D teaching models. With these models, you can interactively learn the tasks and functions of individual muscles that are important for the facial expression. You can rotate the 3D models by holding down the left mouse button and view them from all sides. When you rotate your mouse wheel, you can zoom in and out. On some models, you can click on additional numbers and directly call up the anatomical designation of individual muscles or estimate their topographical position relative to neighboring structures. In addition to other functions, you can switch to full screen mode by pressing the "Full screen” key (bottom right of the image).