Which of the following are extrinsic tongue muscles?

• A. Hyoglossus
• B. Hyoglossus and Genioglossus
• C. Genioglossus
• D. Styloglossus

Answer: (B)

Extrinsic tongue muscles are those that originate outside the tongue and insert into it, moving the tongue as a whole within the mouth. Genioglossus starts on the mandible and fans into the tongue to protrude it, while hyoglossus comes from the hyoid bone and inserts into the tongue to depress and flatten its sides. These two muscles exemplify the extrinsic group because of their outside-origin, inside-insertion arrangement and their roles in positioning the tongue. Styloglossus and palatoglossus are also extrinsic and contribute by retracting/elevating the tongue or elevating the posterior part, respectively, so the concept is clear: muscles that originate outside the tongue and insert into it are the extrinsic movers.