Post date: May 8, 2013 3:40:47 PM
Have you ever met a person who felt an overwhelming need to tell you to be happy, and then, in an attempt and justify their own ambitions, tell you that "it takes less muscles to smile than to frown" and so you should choose to be happier all the time (like an insane person). Well fear no more, now you can say that science is on your side! the pessimist's side!
Muscles involved in a "zygomatic" (genuine) smile:
Zygomaticus major and minor. These muscles pull up the corners of the mouth. They're bilateral (one set on either side of the face). Total number of muscles: 4.
Orbicularis oculi. One of these muscles encircles each eye and causes crinkling. Total: 2.
Levator labii superioris. Pulls up corner of lip and nose. Bilateral. Total: 2.
Levator anguli oris. Also helps elevate angle of mouth. Bilateral. Total: 2.
Risorius. Pulls corner of mouth to the side. Bilateral. Total: 2.
Grand total for smiling: 12
Principal muscles involved in a frown:
Orbicularis oculi (again). Total: 2.
Platysma. Pulls down lips and wrinkles skin of lower face. Bilateral (though joined at midline). Total: 2.
Corrugator supercilii (bilateral) and procerus (unilateral). Furrow brow. Total: 3.
Orbicularis oris. Encircles mouth; purses lips. Unilateral. Total: 1.
Mentalis. Depresses lower lip. Unilateral. Total: 1.
Depressor anguli oris. Pulls corner of mouth down. Bilateral. Total: 2.
Grand total for frowning: 11