5 Affected muscles and actions:
- Frontalis: Raises eyebrows and creates wrinkles on forehead
- Orbicularis oculi: Closes eyelids
- Orbicularis oris: Closes, protrudes, and compresses lips
- Platysma: Depresses mandible and tenses neck skin
- Occipitofrontalis: Lifts eyebrows, pulls scalp, creates horizontal lines on forehead forward.
Mechanism of muscle weakness: Bell's palsy causes the nerve responsible for facial control, which functions through a narrow canal to the face, to swell, usually from infection, affecting tears, saliva, taste, and other bones and muscles.
Other symptoms:
- Drooling
- Difficulty in smiling
- Difficulty in eating/drinking
- Headache
- Loss of taste