Intermediate Medulla Oblongata Quiz

Q1. Where does the pyramidal decussation occur?

• Midbrain tectum
• Rostral pons
• Thalamus
• Caudal medulla

Q2. What happens to fibers arising from the gracile and cuneate nuclei?

• They leave through the hypoglossal nerve
• They enter the optic tract
• They cross as internal arcuate fibers and form the medial lemniscus
• They form the corticospinal tract

Q3. Which nucleus is responsible for branchial motor output carried mainly by cranial nerves IX and X?

• Solitary nucleus
• Nucleus ambiguus
• Gracile nucleus
• Inferior olivary nucleus

Q4. Which medullary nucleus receives visceral sensory information, including taste and cardiopulmonary afferents?

• Solitary nucleus
• Abducens nucleus
• Red nucleus
• Hypoglossal nucleus

Q5. Which nucleus provides parasympathetic preganglionic fibers through the vagus nerve?

• Trochlear nucleus
• Nucleus gracilis
• Dorsal motor nucleus of the vagus
• Inferior salivatory nucleus only

Q6. Which medullary nucleus contains somatic motor neurons for the tongue?

• Cuneate nucleus
• Vestibular nucleus
• Solitary nucleus
• Hypoglossal nucleus

Q7. What is the principal role of the inferior olivary nucleus?

• It directly innervates tongue muscles
• It produces cerebrospinal fluid
• It provides major climbing fiber input to the cerebellum
• It carries visual information to the cortex

Q8. Which structure forms part of the floor of the fourth ventricle in the rostral medulla?

• Optic chiasm
• Rhomboid fossa
• Septum pellucidum
• Corpus callosum

Q9. What distinguishes the closed medulla from the open medulla?

• The closed medulla surrounds the central canal, while the open medulla borders the fourth ventricle
• The closed medulla contains no cranial nerve nuclei
• The closed medulla lies superior to the pons
• The open medulla lacks ascending tracts

Q10. Which major sensory tract carries pain and temperature information through the medulla toward the thalamus?

• Spinothalamic tract
• Fornix
• Corticospinal tract
• Optic radiation