Anatomy and Physiology series: Facial musculature

So...facial muscles...yeah.  I was debating with myself on whether or not I was going to write on the facial musculature that is part of our articulatory system (not all our facial muscles...that would just get way too long.)  To be honest, I'm really eager to get to the nervous system since that's where I feel the really important physiology comes in (and it's the system that is usually ignored in voice pedagogy texts and classes), but I decided, in an effort to be thorough, to include these muscles here just so folks know what they are and what they do.

The first muscle is the orbicularis oris.

This muscle basically makes up your lips (along with a mucus membrane and epithelial layer), and it's your oral sphincter muscle.  Some folks classify this muscle as two separate parts:  The obicularis oris superior and inferior, which makes sense, because the function of the orbicularis oris is to close your mouth.  For reals.  It also serves as a point of insertion for a lot of other facial muscles and moves in conjunction with those other muscles to form a lot of facial gestures.

The risorius muscle (which I always felt is a funny-sounding name for a muscle) comes from the masseter, and inserts into the orbicularis oris.

This guy retracts the lips from the corners.  

Another muscle that also pulls the lips back is the buccinator, which lies deep to the risorius.  

It originates from a ligament (specifically, the pterygomandibular ligament) on the bottom jaw, or mandible, and inserts into the orbicularis oris.  It also helps out a lot during chewing.  

The levator labii superious comes from the upper jaw bone, or maxilla, and inserts into the middle-side of the upper lip. 

This muscle elevates the upper lip when contracted.  

Then we have the zygomatic major and zygomatic minor muscles.  

Zygomatic Major

Zygomatic Minor

Zygomatic major originates from the zygomatic bone and inserts into the corner of the orbicularis oris.  It elevates the upper lip and also pulls back the angle of the mouth.  Zygomatic minor also comes from the surface of the zygomatic bone and inserts into the mid-side of the upper lip. It elevates the upper lip.  

The depressor labii inferioris originates from the mandible and inserts into the lower lip.  

This muscle pulls the lips down and out, which also happens to open the lips up a bit (you can also think of this as the "pouting" muscle).

The depressor anguli oris comes from the mandible and inserts into the orbicularis oris at the upper corners.  

This guy lowers the corners of the mouth and helps to compress the upper lip to the lower lip.  

The mentalis comes from the mandible and inserts into the skin of your chin. 

This muscle pulls the lower lip out, as well as elevating and wrinkling the chin...so this could be thought of as the "pout" muscle's accomplice.  

Also, the platysma, which was mentioned here, makes another appearance, since it lowers the mandible and has a lot to do with jaw movement during speech...along with all the other jaw muscles, that is.  

Okay, so that'll be my last post on musculature for a while.  Now, I can get to what I consider the "fun stuff," the nervous system, physiology of articulation (which follows a bit of nervous system introduction) and a bit of the physics of sound.  Where is this all going?  I suppose I'm building up to my little theory of the relationship between vocal science and vocal pedagogy, what's sometimes missing from that relationship, and how this knowledge has really, really helped my singing along by quite a bit.

*Seikel, J. A., King, D. W., & Drumright, D. G. (2010). Anatomy and physiology for speech, language, and hearing. Clifton Park, NY: Delmar.