cranial nerve| medulla oblongata

CN IX Glossopharyngeal Nerve

The small mixed (both) cranial nerve

what does the CN IX Glossopharyngeal Nerve provide

• Glosso function: Sensory fibers from the posterior one-third of the tongue for taste sensation

• Pharyngeal function: Motor axons to the muscles of the pharynx (throat) involved in swallowing

what is the origin and passage of CN IX Glossopharyngeal Nerve

• Origin: It originates from the superior and lateral side of the medulla oblongata, superior to CN X

• Passage: It's 1st of the 3 cranial nerves that passes through the jugular foramen

where is the CN IX Glossopharyngeal nerve located

CN IX GLOSSOPHARYNGEAL NERVE

CN X Vagus Nerve

This mixed (both) nerve is the only cranial nerve that “wanders” outside of the head and neck (“vagus” means “wanderer”)

whats in and outside of the head of CN X Vagus Nerve

In the head and neck, it provides:

• Some sensory innervation from the skin of the head and pharynx

• Motor axons to muscles involved in speech and swallowing

• Motor axons to certain salivary glands

Outside the head and neck it:

• Innervates most of the thoracic and abdominal viscera as the main nerve of the parasympathetic (rest and digest) nervous system

• Becomes the:

  • Right recurrent laryngeal nerve, which loops around the right subclavian artery

  • Left recurrent laryngeal nerve, which loops around the aortic arch

what is the origin and the passage of CN X Vagus Nerve

• Origin: It originates from the lateral portion of the medulla oblongata and inferior to the CN IX 

• Passage: It's 2nd of the 3 cranial nerves that passes through the jugular foramen

CN XI Accessory Nerve

It is a motor nerve

CN XI Accessory Nerve has 2 cranial nerves

• A cranial component originating from the brainstem 

• A spinal component originating from the spinal cord

what is the origin and passage of the CN XI Accessory Nerve

• Origin: It originates from the lateral portion of medulla oblongata (cranial component) and from C1-C6 of the spinal cord (spinal component), it has a bracket like appearance to it

• Passage: It's 3rd of the 3 cranial nerves that passes through the jugular foramen

where is the CN XI Accessory Nerve

CN XI ACCESSORY NERVE

CN XII Hypoglossal Nerve

It is a small motor nerve

what does CN XII Hypoglossal Nerve innervate

• The muscles that move the tongue

• It does not provide any taste sensation to the tongue

what is the origin and passage of CN XII Hypoglossal Nerve

• Origin: It originates from the anterior and inferior portion of the medulla oblongata

• Passage: It enters through the hypoglossal canal found in the occipital bone

where is the CN XII Hypoglossal nerve located at

CN XII HYPOGLOSSAL NERVE