The primary function of the cervical branch of the facial nerve is to innervate the platysma muscle in the neck.
Cervical Branch of the Facial Nerve: Key Function
The cervical branch, originating from the facial nerve (VII), is crucial for controlling the platysma muscle. Let's explore this further:
The Platysma Muscle
The platysma is a broad, thin muscle located in the superficial fascia of the neck. It extends from the upper chest and shoulder area up to the jawline.
- Function: The platysma's primary functions include:
- Depressing the mandible (lowering the jaw)
- Tensing the skin of the neck
- Drawing down the corner of the mouth
How the Cervical Branch Works
The cervical branch of the facial nerve transmits motor signals that cause the platysma to contract. This allows for a variety of facial expressions and movements related to the neck and lower face. The reference provided states that it "supplies the platysma muscle".
- Clinical Significance: Damage to the cervical branch can result in weakness or paralysis of the platysma muscle, affecting facial expression and neck movement.
Table: Overview of the Cervical Branch Function
| Feature | Description |
|---|---|
| Nerve | Cervical branch of the facial nerve (VII) |
| Target Muscle | Platysma muscle |
| Primary Function | Innervation of the platysma muscle, controlling its contraction and relaxation. |
| Related Actions | Depressing the mandible, tensing neck skin, drawing down mouth corners |
Therefore, the cervical branch of the facial nerve plays a vital role in controlling neck muscle movements, especially the platysma.
