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INTRODUCTION TO NEUROLOGY 



V motor 



Nuc. sal. sup. 



Nuc. sal. inf. 



VII motor 



VII pars. int. 



VIII 



IX motor 



X motor 



XI pars bulbaris 



XI pars spinalis 



Nuc. dorsalis X 



Nuc. ambigu 



V sensory 

 Nuc. sensory V 



VII motor 



VII pars. int. 



VIII 



IX sensory 



X sensory 



Ala cinerea 

 Fasciculus solitarius 

 Nuc. commissuralis Cajal 



Nuc. spinalU V 



Fig. 114. Diagram of the visceral afferent and efferent connections in 

 the medulla oblongata, based on Fig. 71; compare also Figs. 77 and 86. 

 The afferent roots and centers are indicated on the right side ; the efferent, 

 on the left. Visceral sensory fibers enter by the VII nerve (pars intermedia 

 of Wrisberg, VII pars, int.) and by the IX and X nerves. These root-fibers 

 include both general visceral sensory and gustatory fibers, all of which enter 

 the fasciculus solitarius. (Fibers of the IX and X nerves also enter the 

 spinal V tract ; but since these are somatic sensory fibers from the auricular 

 branch they are not included in the diagram. For further details on the 

 composition of these cranial nerves see the table on pp. 146, 147.) 



On the left side of the figure the general visceral efferent nuclei are indi- 

 cated by small dots and the special visceral nuclei by large dots. The 

 latter comprise the motor V nucleus for the jaw muscles, the motor VII 

 nucleus for the muscles related to the hyoid bone and the general facial 

 musculature, and the nucleus ambiguus supplying striated muscles of the 

 pharynx and larynx by way of the IX and X nerves. Three general visceral 

 efferent nuclei are indicated the dorsal motor nucleus of the vagus under 

 the ala cinerea and the superior and inferior salivatory nuclei. The superior 

 nucleus (nuc. sal. sup.) supplies the sublingual and submaxillary salivary 

 glands by way of the VII nerve (pars intermedia of Wrisberg), and the in- 

 ferior nucleus (mic. sal. inf.) supplies the parotid salivary gland by way of 

 the IX nerve. All of the general visceral efferent fibers are preganglionic 

 sympathetic fibers (see p. 229) which end in sympathetic ganglia, whence 

 postganglionic fibers carry the nervous impulses onward to their respective 

 destinations. 



