Queston #13883Note

The facial nerve (CN VII) innervates the stapedius muscle in the middle ear. The stapedius muscle dampens acoustic signals across the stapedius bone. Paralysis of this muscle leads to hyperacusis. The branch to the stapedius muscle is one of the first branches of CN VII. Thus, when hyperacusis is seen secondary to facial nerve dysfunction, it is indicative of a very proximal lesion.