Central facial palsy

Central facial palsy (colloquially referred to as central seven) is a symptom or finding characterized by paralysis or paresis of the lower half of one side of the face. It usually results from damage to upper motor neurons of the facial nerve.

The facial motor nucleus has dorsal and ventral divisions that contain lower motor neurons supplying the muscles of the upper and lower face, respectively. The dorsal division receives bilateral upper motor neuron input (i.e. from both sides of the brain) while the ventral division receives only contralateral input (i.e. from the opposite side of the brain).