A grin, which is made up mostly of sagging muscles on either side of the mouth, is a type of facial expression. A Duchenne smile, for example, is a tightening of the muscles around the eyes.
Smiles are used to conveying joy to people. It differs from an anxiety grimace in that it expresses pleasure rather than concern.
Throughout the world, studies show that smiling is a way to communicate, although there are many cultural differences in how often and why people smile.
For example, some cultures may use smiles when they are feeling embarrassed or confused.
What are the muscles of facial expression?
There are 17 muscles in the human face. These muscles move the skin and underlying structures, such as the eyes, nose, and mouth.
The muscles of the face can be divided into two main groups:
The muscles of facial expression
These are the muscles that control the movement of the skin and underlying structures, such as the eyes, nose, and mouth.
The muscles of facial expression include:
- Orbicularis oculi
- Zygomaticus major
- Levator labii superioris alaeque nasi
- Depressor labii inferioris
- Depressor anguli oris
The muscles of the head and neck
These are the muscles that control the movement of the head and neck.
The muscles of the head and neck include:
- Splenius capitis
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How many muscles does it take to smile?
The muscles used in smiling are not very large, and they don’t require a lot of effort to activate. In fact, it takes only the contraction of two facial muscles to produce a smile.
The zygomaticus major is a muscle that originates at the cheekbone and inserts into the corners of the mouth. This muscle is responsible for the upturning of the lips when we smile.
The other muscle involved in smiling is the orbicularis oculi, which encircles the eye. When this muscle contracts, it pulls the lips upward and to the side, which creates the “crinkling” around the eyes that are often seen in genuine smiles.
The zygomaticus major and orbicularis oculi are both activated by the facial nerve (the seventh cranial nerve). This nerve also innervates other muscles of the face, such as the muscles used in frowning.
In addition to the facial nerve, smiling is also controlled by the motor cortex of the brain.
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Is it harder to frown or smile?
It takes more effort to frown than it does to smile. This is because smiling uses the muscles in a way that they are not used when we frown.
When we frown, our brows contract and pull our lips down, this action uses the same muscles that we use to squint, so it doesn’t require much extra effort.
Smiling, on the other hand, uses a different set of muscles. The zygomaticus major muscle pulls the corners of our mouths up, while the orbicularis oculi muscle contracts around our eyes.
This combination of muscle movements is what gives a smile. It is characteristic of “crinkling” around the eyes.
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The takeaway from all of this is that smiling is a universal way to communicate joy, but the facial muscles used to produce a smile are not very large.
It takes only the contraction of two facial muscles, the zygomaticus major and orbicularis oculi, to create a smile. These muscles are controlled by the facial nerve and the motor cortex of the brain.
All of this information is important to know because it helps us understand how we can create a genuine smile that will be sure to put a smile on someone else’s face as well.
Now go out there and spread some joy!