Archives of neurology and psychiatry Volume 7

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1922 Excerpt: ...out the posterior funiculi and any part of the posterior gray columns as the pathway for the conduction of this type of visceral afferent impulse. This is in contradistinction to the findings of Ranson and von Hess, working-with somatic nerves, since they found the pressor pathway within the cord to be situated in the apexes of the posterior horns. Neither does complete lateral hemisection cause a disappearance of the pressor response to thoracic sympathetic stimulation. This is true whether the nerve on the side of the lesion or on the opposite side is stimulated. This strongly suggests that whatever the pathway within the cord, it obviously must be one which ascends partly on the homolateral and partly on the contralateral side. Section of the lateral funiculi, including a portion of one of the anterior gray columns, has resulted in a slight decrease in the height of the pressor response; but the characteristic rise still remains. A lesion of the anterior funiculi had no influence on the blood pressure curve. The only lesion produced which destroyed this pressor response from stimulation of the thoracic sympathetic nerve was a complete transverse section of the spinal cord. It is reasonable to presume, therefore, that the impulses arising from the viscera, transmitted through the thoracic sympathetic nerve and giving rise to vasomotor and respiratory responses, are conducted upward by relays of short spinal paths with synapses in the gray matter of the spinal cord. If this be true, they resemble fibers which convey pain sensation in the cat from the periphery. Since complete transection of. the spinal cord at the level of the second thoracic segment eliminated the pressor response, it is obvious that the reflex arc is not complete within the spinal cord a...