- Muscle: Occipitofrontalis
- Action: draws scalp anteriorly, raises eyebrows, and wrinkles skin of forehead
- Muscle: Orbicularis oculi
- Action: closes eye
- Muscle: Buccinator
- Action: presses cheeks against teeth and lips, as in whistling, blowing, and sucking; draws corner of mouth laterally; and assists in mastication (chewing) by keeping food between the teeth (and not between teeth and cheeks)
- Muscle: Zygomaticus major
- Action: draws angle of mouth superiorly and laterally
- Muscle: Orbicularis oris
- Action: closes and protrudes lips, as in kissing; compresses lips against teeth; and shapes lips during speech.
Bell's palsy or facial paralysis is caused by the damage or disease of facial (VII) nerve. Possibly caused by inflammation of the facial nerve or infection by the herpes simplex virus, this causes the entire side of the face to droop.
John Hopkins Medicine states that aside from this, other symptoms of Bell's palsy include headache, tearing, drooling, loss of sense of taste on the front of the tongue, and hypersensitivity of affected ear.