Zygomaticus major

A muscle that plays a key role in facial expression, particularly in smiling.

Zygomaticus major is a paired muscle located in the facial region. It extends diagonally from the zygomatic bone (also known as the cheekbone) to the corners of the mouth. This muscle is instrumental in elevating the corners of the mouth and is primarily responsible for the human smile. It enables an array of facial expressions, reflecting emotions and social cues.

Terminologia Anatomica

musculus zygomaticus major

System

Muscular system

Function

The primary function of zygomaticus major is to facilitate facial expressions, specifically those associated with joy and happiness. When this muscle contracts, it pulls the corners of the mouth upwards and outwards, creating the characteristic shape of a smile. This extension and elevation are essential not just for personal expression, but also for effective non-verbal communication. The movement of the zygomaticus major can influence emotional states, as it is linked to the release of endorphins and can contribute to a positive feedback loop of emotional well-being. Beyond the smile, it assists in other facial movements, lending dynamism to expressions of laughter or excitement, thereby enhancing social interactions and connections among people.

Location

Zygomaticus major is located in the mid-facial region. It originates from the lateral part of the zygomatic bone, which is situated in the upper cheek area, and it courses downwards and forwards to insert into the skin at the angle of the mouth, specifically at the modiolus, a point where several facial muscles converge. This strategically advantageous position allows the muscle to play a pivotal role in altering the contour of the face as well as the position of the mouth, enabling a range of expressive movements. Its proximity to other facial muscles, such as the buccinator and risorius, also contributes to the overall aesthetics and functionality of facial expressions.

Did You Know?

The zygomaticus major is sometimes referred to as the 'smiling muscle' due to its significant role in creating smiles.
This muscle is one of the key muscles involved in non-verbal communication, indicating happiness or enthusiasm.
The tone and strength of the zygomaticus major can influence the perceived authenticity of a smile, distinguishing between genuine and polite smiles.
Injuries or conditions affecting the zygomaticus major can lead to facial asymmetry or difficulties with expression, affecting emotional communication.