Medulla at the sensory decussation

Medial Longitudinal Fasciculus

A medial bundle that includes the tectospinal and medial vestibulospinal tracts, both extrapyramidal tracts from the brainstem to the cervical spinal cord.

Sensory

Gracile and cuneate fasciculi and nuclei, spinal nucleus of CN V Internal arcuate fibers Medial Lemniscus Medial Longitudinal Fasciculus Accessory Cuneate Nucleus Solitary Nucleus and Tract

This level looks like a

Moose head

Motor parts at this level

Pyramids medial longitudinal fasciculus Hypoglossal Nucleus Principal (inferior) olivary nucleus

Posterior Spinal Artery

Supplies nucleus Gracilis and cuneatus

Anterior Spinal Artery

Supplies the pyramid, the medial lemniscus, and medial structures all the way up to the center (hypoglossal nucleus)

PICA and Vertebral artery

Supply the lateral structures

Internal Arcuate Fibers

decussation the axons of second order neurons located in the gracile and cuneate nuclei. Once crossed, these fibers form the contralateral *Medial lemniscus.* *Medial longitudinal fasciculus* is deep to the medial lemniscus

Accessory Cuneate Nucleus

second order neurons carrying *non-conscious proprioception.* These cells *project to the cerebellum.* The nucleus receives fibers from the cuneocerebellar tract. These fibers will go up through cerebellar peduncle into the cerebellum

Solitary Nucleus and Tract

the inferior part of nucleus solitarius is located lateral to CN XII nucleus. It *contains GVA neurons and receives fibers for CNs IX and X*. The nucleus is surrounding the tract

Hypoglossal Nucleus

the lower part of the hypoglossal (CN XII) nucleus is located near the midline. These are LMNs that innervate the tongue (hypoglossal nerve)

Principal (inferior) olivary nucleus

this motor nucleus supplies major input to the contralateral cerebellum. The fibers cross and enter the contralateral inferior cerebellar peduncle. The nucleus receives fibers from numerous motor centers