What combination of functions does the Glossopharyngeal nerve control?

The Glossopharyngeal nerve is crucial for both swallowing and certain sensory functions. It primarily plays a significant role in the process of swallowing by innervating the muscles of the pharynx, which are essential for the action of swallowing. Additionally, it is responsible for providing sensory information from the oropharynx and the posterior third of the tongue, including the perception of taste in that area.

Furthermore, the Glossopharyngeal nerve contributes to the gag reflex and the sensation of the mucous membranes of the throat. Its sensory functions encompass not only taste but also the detection of carotid body and carotid sinus inputs, which are vital for regulating blood pressure and respiratory function.

In contrast, while salivation and speech involve different cranial nerves, the functions of tongue movement and balance are primarily regulated by other nerves. Hearing pertains to the auditory system, primarily controlled by the vestibulocochlear nerve. Hence, the combination of swallowing and sensory functions accurately encapsulates the primary roles of the Glossopharyngeal nerve.