I don't have anything witty to say about the jaw and its role in communication so we'll simply be direct in this post.

Jaw Function - What Does the Jaw Do?

Your jaw opens and closes using muscles.

Sure, you can shift your jaw left and right a bit BUT for speech, the main function of interest is jaw opening and closing.

The condyle of the mandible or jawbone acts as the hinge point where the jawbone swivels. Depending on the direction of swivel, it shifts your mouth from a closed mouth position to an open mouth position or vice versa.

This function is of interest for many things including:

speaking,
chewing,
yawning,
and mouth-breathing

How Does Jaw Opening & Closing Impact Speech?

So your jaw opens and closes.

Big deal.

Why is that important for speech?

1. Vowels.

Vowel production is largely dependent on jaw opening in addition to breath support and vocal cord vibration. Mouth opening (based on how wide or narrow your jaw opening is) along with lip shape and tongue position impact the final vowel produced. The jaw, lips and tongue are the articulating components that can shape the sound.

Consider the sounds when you say the letter "E" and the letter "A". Notice how different the jaw position is for those two sounds.

"E" "A"

Notice how closed the mouth is when you say "E" but how wide your mouth is when you say "A". You cannot say "A" without opening your mouth wider and you cannot see "E" without keeping your mouth fairly closed. Without knowing the relative amount of jaw opening needed for vowels, it can be extremely hard for you to produce the correct sound

2. Loudness

Do you ever sing, act in a play, or speak for formal presentations?

By opening the mouth and projecting your voice, you are allowing the sound to come out. If you do not move your mouth much or you tend to keep your mouth closed more, then you are stifling or reducing your vocal projection. The concept is similar to a musical mute used to soften or alter the tone of an instrument like a trumpet or trombone.

People who are shy or quiet often mumble their words more because they are not using their diaphragm to actively exhale their breath with force or they are not projecting their voice through manipulation of their articulators such as jaw opening enough.

Look at this opera singer, Paul Potts, and how wide open his mouth is when he is singing. The visual of his wide open mouth and the rounded lips does wonders for his vocal projection.

3. CLARITY & OVER-ENUNCIATION

By over-exaggerating or over-enunciating your sounds by taking your time with your jaw opening (along with your tongue and mouth shapes), you are making the clearest sounds. If you speak too quickly or mumble, you don't achieve the optimal mouth shape for those sounds. Sure, you may get close to the correct sound or good enough that people can understand, but it isn't optimal. Achieving optimal mouth shape by taking the time to get to the right amount of jaw opening helps you achieve the clearest sound.

Taking the time to over-enunciate is also a strategy to pace yourself better because of the extra time required. By focusing on over-enunciating, you are subconsciously slowing your pace down, which can help with nervousness in presentations, command attention and improve your communicative success.

By practicing grading your jaw movements and becoming more precise with the amount of jaw opening needed to achieve the correct sound, you can precisely articulate your sounds. Too much jaw opening can entirely change the sound you want. Too little jaw opening can also muffle or distort the sound you want. Knowing the relative jaw opening needed for an "E" or "A" as well as the jaw opening needed for a "U" or O" matters.

Try reading aloud or speaking aloud in front of a mirror. Watch how wide or how narrow your mouth opening is. Think about the feedback you have gotten in the past about your pronunciation, volume, or pace. Jaw positioning may be the unlock for you to take your communication skills to the next step. And if not, at least you now know a little more about jaw involvement in your communication.

Let me know down below if you already knew all this information already. Am I being redundant or thinking I’m helping when I’m simply repeating things you already know?

Jaw 😮 (can’t make this Face Without jaw control)