Which nerve is involved in taste sensation from the anterior two-thirds of the tongue?

The facial nerve, also known as cranial nerve VII, is primarily responsible for taste sensation from the anterior two-thirds of the tongue. It innervates taste buds located in this region through its chorda tympani branch, which joins the lingual nerve, a branch of the mandibular division of the trigeminal nerve. This connection allows sensory information regarding taste to be conveyed to the brain.

In addition to its role in taste, the facial nerve also serves other functions, including motor control of facial expressions and secretion from glands such as the lacrimal and salivary glands. Understanding this relationship is crucial for grasping how cranial nerves interact with sensory functions.

The glossopharyngeal nerve primarily handles taste from the posterior one-third of the tongue, contributing to the broader sensory perception of taste but not the anterior portion where the facial nerve is active. The abducens nerve is involved in eye movement and has no role in taste sensation. Similarly, the vagus nerve, while it has diverse functions including innervation of the throat and digestive system, does not participate in taste sensation specifically from the tongue. Therefore, the significance of the facial nerve in taste sensation is clear and distinct.