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NEUROLOGY 





the vagus and glossopharyngeal nerves, and is associated with the vestibular pan; 

 of the acoustic nerve and the sensory root of the facial nerve. Still higher, it forms a 

 mass of pigmented cells the locus caeruleus in which some of the sensory fibers 

 of the trigeminal nerve appear to end. The head of the posterior column forms a 

 long nucleus, in which the fibers of the spinal tract of the trigeminal nerve largely 

 end. 



Auditory radiation 

 Medial geniculate 



Inferior coUiculus 



N. V 

 Nucleus incertus 



Vestibular nucleus 

 Cochlear nucleus 



Stria terminalis 



Lateral lemniscus 



Inferior peduncle 



Dorsal external 

 arcuate fibers 



External arcuate 

 fibers 



Nucleus cinerea 

 Nucleus cuneatus \ !& 



Nucleus gracilis 



Nucleus spinal 

 tract, trigem- 

 inal 



FIG. 691. Dissection of brain-stem. Dorsal view. The nuclear masses of the medulla are taken from model by 



Weed, Carnegie Publication, No. 19. 



The dorsal spinocerebellar fasciculus (fasciculus cerebellospinalis; direct cerebellar 

 tract) leaves the lateral district of the medulla oblongata ; most of its fibers are carried 

 backward into the inferior peduncle of the same side, and through it are conveyed 

 to the cerebellum; but some run upward with the fibers of the lemniscus, and, 

 reaching the inferior colliculus, undergo decussation, and are carried to the 

 cerebellum through the superior peduncle. 



The proper fasciculi (basis bundles) of the anterior and lateral funiculi largely 

 consist of intersegmental fibers, which link together the different segments of the 

 medulla spinalis; they assist in the production of the formatio reticularis of the 

 medulla oblongata, and many of them are accumulated into a fasciculus which 

 runs up close to the median raphe between the lemniscus and the rhomboid fossa ; 



