Muscle 1: Orbicularis Oculi
Action: Closes eye
Effect: Difficulty in closing eye
Muscle 2: Orbicularis Oris
Action: Closes and puckers lip that are needed in speaking
Effect: Lips droop, difficulty in speaking
Muscle 3: Zygomaticus Major
Action: Elevates corner of mouth
Effect: Asymmetric smile, other side of the face is not elevated properly
Muscle 4: Buccinator
Action: Compress cheeks against teeth; essential in chewing
Effect: Difficulty in chewing, may bite cheek more often
Muscle 5: Occipofrontalis
Action: Elevation of eyebrows and wrinkles the forehead
Effect: Flattened forehead and difficulty in raising the eyebrow
Mechanism: Bell's palsy is also known as facial paralysis. It is due to the damage of the facial (VII) nerve. Possible causes may include inflammation of the facial nerve due to infection.
Other symptoms: It is similar to the symptoms of stroke. Patient may also experience eye issues, difficulty in eating/drinking, drooling, and loss of taste/appetite. This is all due to the malfunction and disorders manifested in the targeted muscles.