Human Anatomy

Depressor anguli oris

A muscle that plays a key role in facial expressions, particularly in frowning and the downward movement of the corners of the mouth.

Located in the lower part of the face, the depressor anguli oris is a small but significant muscle that originates from the mandible and inserts into the skin at the angle of the mouth. It is part of the group of muscles known as the facial muscles, which are primarily responsible for controlling facial expressions.

Terminologia Anatomica

depressor-anguli-oris

System

Muscular system

Function

The primary function of the depressor anguli oris is to facilitate the depression of the corners of the mouth, contributing to facial expressions associated with sadness or displeasure. When this muscle contracts, it pulls the corners of the mouth downward and outward, enhancing the ability to communicate emotions non-verbally. This muscle also supports the functionality of other facial muscles during expressive actions, such as frowning or grimacing. In addition, its role in expression can impact interpersonal communication and social interactions, highlighting the importance of facial anatomy in conveying human emotions.

Location

Situated in the lower facial region, the depressor anguli oris is positioned at an angle to the mandible, specifically at the outer surface of the body of the mandible. It begins at the mental protuberance, which is located in the center of the mandible, and extends upward to blend with the skin and the orbicularis oris muscle at the angle of the mouth. This strategic location enables it to efficiently pull down the corners of the mouth, making it a pivotal player among other facial muscles in the overall range of movement and expression.

Did You Know?

The depressor anguli oris is often referred to as the 'frowning muscle' due to its primary role in expressing sadness.
This muscle is one of several that work together to create complex facial expressions that can indicate a wide range of emotions.
Despite its small size, the depressor anguli oris can significantly influence how others perceive a person's emotional state.