Bifid Zygomaticus Major In faces with dimples, the bundles of the zygomaticus major separate into two bundles so that the skin gets pulled inward as the muscle contracts.

It turned out that the activity of zygomaticus major (the ‘smiling muscle’), heart rate variability and EEG indicators can tell us most about the viewer’s impression of the movie.

Each smile hinges on an anatomical feature known as the zygomaticus major, straps of facial muscle below the cheekbones that pull up the corners of the mouth. But it's not the only muscle at work.

Muscles that are made up of more “slow-twitch” fibres are better for longer, sustained facial movements. ... and the zygomaticus major muscle, which is around the mouth.

The first group is associated with the corners of the mouth – where, for example, the risorius (from the Latin to smile) draws the corners outward and the zygomaticus major muscle lifts them.

The first group is associated with the corners of the mouth – where, for example, the risorius (from the Latin to smile) draws the corners outward and the zygomaticus major muscle lifts them.