Which cranial nerve controls tongue movement (motor)?

• A. Glossopharyngeal (IX)
• B. Hypoglossal (XII)
• C. Vagus (X)
• D. Accessory (XI)

Answer: (B)

Tongue movement is driven by a nerve that provides motor innervation to all intrinsic tongue muscles and most of the extrinsic ones, enabling actions like protrusion, retraction, and shaping for speech and swallowing. This nerve originates in the medulla and reaches the tongue to activate muscles such as genioglossus, hyoglossus, and styloglossus. Other cranial nerves have different roles: one mainly handles a muscle of the throat and salivation, another governs pharyngeal and laryngeal muscles (and the palatoglossus), and another supplies neck muscles—none of these directly control tongue movement. Therefore, the nerve that controls tongue movement is the hypoglossal nerve.