Posterior auricular nerve
The posterior auricular nerve arises from the facial nerve close to the stylomastoid foramen and runs upward in front of the mastoid process; here it is joined by a filament from the auricular branch of the vagus and communicates with the posterior branch of the great auricular as well as with the lesser occipital.
As it ascends between the external acoustic meatus and mastoid process it divides into auricular and occipital branches.