Which cranial nerve is responsible for controlling tongue movements?

• A. CN IX (Glossopharyngeal Nerve)
• B. CN VII (Facial Nerve)
• C. CN X (Vagus Nerve)
• D. CN XII (Hypoglossal Nerve)

Answer: (D)

The cranial nerve that is responsible for controlling tongue movements is the Hypoglossal Nerve, which is designated as cranial nerve XII. This nerve innervates the majority of the intrinsic and extrinsic muscles of the tongue, enabling it to perform various functions such as movements for speech, swallowing, and manipulation of food within the mouth. Proper functioning of the Hypoglossal Nerve is essential for articulating sounds and coordinating the complex movements required for effective communication as well as safe swallowing.

In contrast, the other cranial nerves listed have different primary functions. The Glossopharyngeal Nerve (CN IX) is primarily involved in taste from the posterior one-third of the tongue and contributes to swallowing and salivation but does not directly control tongue movements. The Facial Nerve (CN VII) is key for facial expressions and conveys taste sensations from the anterior two-thirds of the tongue but does not innervate the muscles responsible for movement. The Vagus Nerve (CN X) plays a significant role in autonomic functions and also has some involvement in swallowing but does not control the movements of the tongue itself. Thus, the specific role of the Hypoglossal Nerve in maneuvering the tongue solidifies its status as the