Which cranial nerve controls the muscles for facial expressions?

The facial nerve is responsible for controlling the muscles of facial expression. It innervates the muscles that allow for a variety of expressions, including smiling, frowning, and raising the eyebrows. This nerve also plays a role in the sensation of taste from the anterior two-thirds of the tongue and provides some autonomic functions, such as tear and saliva production.

Understanding the functions of other cranial nerves provides clarity in distinguishing their roles. The vagus nerve primarily affects involuntary functions throughout the body, such as heart rate and digestion, rather than facial muscle movements. The oculomotor nerve controls pupil constriction and most eye movements, focusing on the orbit rather than facial expression. The trigeminal nerve mainly handles sensation in the face and motor functions like mastication, rather than the muscles associated with facial expressions. Therefore, the facial nerve is specifically tasked with the complex activity of facial musculature.