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TEXT-BOOK OF PHYSIOLOGY 



to prove that the nerve impulses cross the median line of the cord immedi- 

 ately or very shortly after entering and then ascend the corresponding half 

 of the cord on their way to the thalamus. At the same time, muscle sen- 



FIG. 233. DIAGRAM OF THE SENSOR PATHWAYS IN THE SPINAL CORD ENLARGED ABOVE BY 

 FIBERS OF THE SENSOR CRANIAL NERVES AND NERVES OF SPECIAL SENSE. 



sibility is abolished on the same below the injury. This would seem to 

 prove that the fibers of the posterior roots that enter and cross the 

 column of Burdach and ascend in the column of Goll to terminate around the 

 cells of the gracile and cuneate nuclei are derived mainly from the muscles. 



