Scientists Pinpoint Zygomaticus Major Muscle as Key to Human Smiles
Scientists have identified the zygomaticus major muscle, also known as the greater zygomatic muscle, as a key player in human facial expressions. This muscle, located in the cheek, plays a crucial role in forming smiles.
The zygomaticus major muscle originates at the zygomatic bone near the zygomaticotemporal suture, at the base of the skull. It extends to the corner of the mouth, drawing the mouth's angle upward and outward when activated. This action is responsible for the upward curve of the lips during a smile.
This muscle, part of the muscles of facial expression, is innervated by the facial nerve, specifically cranial nerve VII. It is susceptible to various conditions, including myalgia strains, neuromuscular diseases, lacerations, contusions, Bell's palsy, infectious myositis, and myopathy. These conditions can affect its function and cause facial asymmetry or weakness.
The zygomaticus major muscle's primary function is to control facial expression, specifically the upward and outward movement of the mouth's corners. Its variation can result in dimples. Understanding this muscle's anatomy and potential afflictions can aid in diagnosing and treating facial muscle disorders.
