The anatomy of the nervous system, from the standpoint of development and function . cic region of the spinal cord. Just before terminating thesefibers cross in the anterior white commissure. They end like those of the lateralcorticospinal tract, either directly or perhaps through an intercalated neuron,in relation to the motor cells in the anterior column. The crossing of theselibers is only delayed, and it will be apparent that all of the corticospinal fibersarising in the right cerebral hemisphere terminate in the anterior column of theleft side of the cord, and conversely, those from the l
The anatomy of the nervous system, from the standpoint of development and function . cic region of the spinal cord. Just before terminating thesefibers cross in the anterior white commissure. They end like those of the lateralcorticospinal tract, either directly or perhaps through an intercalated neuron,in relation to the motor cells in the anterior column. The crossing of theselibers is only delayed, and it will be apparent that all of the corticospinal fibersarising in the right cerebral hemisphere terminate in the anterior column of theleft side of the cord, and conversely, those from the left hemisphere end on theright side. It is along these fibers that impulses from the motor portion of thecerebral cortex reach the cord and bring the spinal motor apparatus undervoluntarv control. Fasciculus septomarginalis Fasciculus gracilis Fasciculus inlerfasciciilaris Fascicillus proprius , Sensory fibers of thesecond orderLateral corticospinal_tract Rubrospinal tract— Tectospinal tract - Fasciculus proprius- Bulbospinal trad —Vestibulospinal tract ,,-Fasciculus cuneatus. -Dorsolateral fasciculus _^s Dorsal spinocerebellartrad \ Fasciculus proprius Ventral spinocere-bellar spinothalamictract Spinotectal trad — Ventral root Ventral spinothalamic trad Sulcomarginal fasciculusVentral corticospinal trad Fig. 78.—Diagram showing the location of the principal fiber tracts in the spinal cord of tracts on the right side, descending tracts on the left. It is stated by some authors, although on the basis of rather unsatisfactory evidence,that the fibers of the lateral corticospinal tract ramify in the formatio reticularis (Mona-kow. 1895) and the nucleus dorsalis (Schafer, 1899). The corticospinal path is from thestandpoint of phylogenesis a relatively new system and varies a great deal in differentmammals. It is found in the ventral funiculus in the mole, while in the rat it occupies theposterior funiculus. In the mole it is almost completely un
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectnervoussystem, bookye
