This is called essential blepharospasm or hemifacial spasm. The entire set of muscles may be involved or half may be affected (mehifacial).
mentralis buccula
orbicularis oris
buccinator muscle
They are called circular. Examples include the orbicularis oris and orbicularis oculi.
The antagonist of the orbicularis oris muscle is the depressor anguli oris muscle. It is responsible for depressing the angle of the mouth, which opposes the action of the orbicularis oris muscle that closes and puckers the lips.
orbicularis oris
orbicularis oris
The arrangement of the fascicles in orbicularis oris is circular.
Muscles that are used for kissing are 34 facial muscles, and 112 postural muscles. The most important one is orbicularis oris muscle, which encircles mouth.
orbicularis oris
orbicularis oris
The eyes' muscle group is the orbicularis oculi