The muscle most responsible for smiling is the zygomaticus major. This muscle is located in the cheek and connects to the corner of the mouth and the cheekbone. When it contracts, it pulls the corner of the mouth upwards and outwards, creating a smile.
While the zygomaticus major is considered the primary "smiling muscle," other muscles also contribute to the formation of a smile. These include the risorius, which pulls the corners of the mouth laterally (outwards), and the orbicularis oculi, which contracts to form wrinkles around the eyes, creating a "crinkle-eyed" smile.
A genuine smile, also known as a Duchenne smile, involves both the zygomaticus major and the orbicularis oculi muscles, resulting in a more authentic and expressive smile.
