ACTIVITY 4
Affected Muscles and Actions:
- Orbicularis Oculi Muscle:
- Action: Responsible for closing the eyelids, blinking, and squinting.
- Orbicularis Oris Muscle:
- Action: Involved in closing and pursing the lips, contributing to facial expression.
- Frontalis Muscle:
- Action: Elevates the eyebrows and plays a role in forming forehead wrinkles.
- Buccinator Muscle:
- Action: Compresses the cheeks against the teeth, aiding in activities like blowing and whistling.
- Zygomaticus Major Muscle:
- Action: Elevates the corners of the mouth, facilitating smiling.
Mechanism of Muscle Weakness:
- Bell's palsy is associated with damage or disease of the facial (VII) nerve. Potential causes include inflammation of the facial nerve due to factors such as ear infection, ear surgery affecting the facial nerve, or infection by the herpes simplex virus. The condition results from compression of the facial nerve within the narrow facial canal, disrupting the nerve's ability to transmit signals to the affected facial muscles.
Other Potential Symptoms:
- Altered taste sensation on the front two-thirds of the tongue.
- Increased tearing or dryness of the eye on the affected side.
- Heightened sensitivity to sound in one ear on the affected side.
- Difficulty fully closing the eye on the affected side, potentially leading to eye dryness and corneal damage.
- Difficulty articulating sounds and words due to involvement of muscles around the mouth.
References:
The Facial Paralysis Institute. (2023, May 29). Bell’s Palsy - Bell’s Palsy symptoms and treatment. https://www.facialparalysisinstitute.com/conditions/bells-palsy/
Tortora, G., & Derrickson, B. (2012). Principles of ANATOMY & PHYSIOLOGY (13th ed.). John Wiley & Sons, Inc.