Which nucleus involved in tongue movements is located in the upper medulla?

Which nucleus involved in tongue movements is located in the upper medulla?

• A. Hypoglossal nucleus
• B. Abducens nucleus
• C. Trochlear nucleus
• D. Facial nucleus

Answer: (A)

Tongue movements are controlled by the hypoglossal nerve, whose motor nucleus sits in the upper part of the medulla along the midline near the floor of the fourth ventricle. This medial, rostral medullary location is characteristic for the nucleus that innervates the intrinsic and extrinsic tongue muscles. The other nuclei are located elsewhere: the abducens nucleus is in the caudal pons and drives lateral eye movement; the trochlear nucleus is in the midbrain for the superior oblique; the facial nucleus is in the caudal pons for facial expression muscles. So the nucleus linked to tongue movements and located in the upper medulla is the hypoglossal nucleus.

Tongue movements are controlled by the hypoglossal nerve, whose motor nucleus sits in the upper part of the medulla along the midline near the floor of the fourth ventricle. This medial, rostral medullary location is characteristic for the nucleus that innervates the intrinsic and extrinsic tongue muscles. The other nuclei are located elsewhere: the abducens nucleus is in the caudal pons and drives lateral eye movement; the trochlear nucleus is in the midbrain for the superior oblique; the facial nucleus is in the caudal pons for facial expression muscles. So the nucleus linked to tongue movements and located in the upper medulla is the hypoglossal nucleus.