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INTRODUCTION TO NEUROLOGY 



Faac. 



Faac. cuneai 



Fasc. scpto-marg. 



Fasc. inter-fascie. 



Tr. cortico-spin. lat 



Tr. rubro-epin. 



Nuc. dorso-lat. 



Nuc. ventro-med. 



Nuc. ventro-lat. 



Tr. cortico-spin. ven . 



Tr. olivo-spinalis 



Tr. tecto-spinalis 



Tr. vestibulo-spin. 



Radix ventralis 



Radix dorsalis 

 Fasc. dorso-lat. 

 Tr. spino-cereb. dor. 

 Columna dorsalis 

 Fasc. proprius dors. 

 Fasc. proprius lat. 

 Tr. spino-cereb. ven. 

 Tr. gpino-thalam. lat. 

 Columna ventralis 

 Tr. gpino-tectalis 

 Tr. spino-thalam. ven. 

 Tr. spino-olivaris 

 Fasc. proprius ven. 

 Fasc. sulco-marg. 



Fig. 59. Diagram of a cross-section through the human spinal cord at 

 the level of the fifth cervical nerve, to illustrate arrangement of the fiber 

 tracts in the white matter and of the nerve-cells in the gray matter of the 

 ventral column. On the right side the area occupied by the dorsal gray 

 column (posterior horn) is stippled; on the left side some of the groups of 

 cells of the ventral gray column (anterior horn) are indicated. In the white 

 matter the outlines of some of the more important tracts are schematically 

 indicated, ascending fibers on the right side and descending fibers on the 

 left. The same area of white matter is in some cases shaded on both sides 

 of the figure. This indicates that ascending and descending fibers are 

 mingled in these regions. A list of the tracts here illustrated follows. The 

 names here employed in some cases differ from those of the official German 

 Anatomical Society list (see p. 115), the B. N. A. terms here being italicized. 



ASCENDING TRACTS 



Fasciculus gracilis (column of Goll) and fasciculus cuneatus (column of 

 Burdach.) These are mixed bundles which in the aggregate make up the 

 greater part of the dorsal funiculus (old term, posterior columns). They are 

 made up chiefly of the ascending branches of dorsal root fibers (see Fig. 61 ), 

 those in the gracilis from the sacral, lumbar, and lower thoracic nerves (S, 

 L, T5-12), and those in the cuneatus from the upper thoracic and cervical 

 nerves (Tl-4, C), as indicated in the figure. These fasciculi terminate 

 respectively in the nuclei of the fasciculus gracilis (clava) and cuneatus 

 (tuberculum cuneatum) at the lower end of the medulla oblongata (cf. Fig. 

 83), and conduct chiefly impulses of the proprioceptive reflexes and those 

 concerned with sensations of posture, spatial discrimination, and the co- 

 ordination of movements of precision (see pp. 137, 175). 



Fasciculus dorse-lateral is (tract of Lissauer, Lissauer's zone), made up 

 chiefly of unmyelinated fibers from the dorsal roots, together with myelin- 

 ated correlation fibers of the fasciculus proprius system. 



Tractus spino-cerebellaris dorsalis (fasciculus cerebeUo-spinalis, direct 

 cerebellar tract, Flechsig's tract) . These fibers arise from the neurons of the 

 nucleus dorsalis (Clarke's column of gray matter between the dorsal and 

 ventral gray columns in the thoracic region, also called Stilling's nucleus) 

 of the same side and enter the cerebellum by way of its inferior peduncle 

 (corpus rcstiforme). 



Tractus spino-cerebellaris ventralis (part of Cowers' tract, or the fascicu- 

 lus anlero-lateralis superficialis of the li. N . A .). These fibers also arise from 

 the nucleus dorsalis of the same side (A. N. Bruce) in the lower levels of the 



