The Place of Incidence of Reflex Fatigue

Abstract

The APS Journal Legacy Content is the corpus of 100 years of historical scientific research from the American Physiological Society research journals. This package goes back to the first issue of each of the APS journals including the American Journal of Physiology, first published in 1898. The full text scanned images of the printed pages are easily searchable. Downloads quickly in PDF format.

Post-Tetanic Potentiation of Response in Monosynaptic Reflex Pathways of the Spinal Cord

“…Post-tetanic increments of response have been encountered too in the study of spinal reflex mechanisms (5,14,36,38). However, it is widely recognized that analysis of mechanism in the central nervous system at once is confronted with a new factor, the activity of internuncial chains.…”

Reflex mechanisms and the physiology of nerve.

“…If, now, when a unilateral stimulation H 1 to afferent nerve has set up ipsilateral flexion and contralateral extension in two symmetrical limbs, the symmetrical afferent nerve of the opposite side be stimulated, the new stimulus commonly breaks through the effect of the old, the flexed limb is extended and the extended limb is now flexed-a step has been taken. The results attained by similar compounding of stimuli have been discussed at length by Sherrington (30,31,32), Brown (6,7,8,10,11,12), and Forbes (13,14). The striking point now is that if two opposing reflex stimuli, as above described, are given continuously and simultaneously (faradic stimulation) each reflex will alternately inhibit the other, and a rhythmical movement of progression results.…”

“…The reviewer does not see how it solves the difficulty.) The essential feature of this view lies in the "inhibitory fatigue," which Sherrington and Forbes (14) locate at synapses.…”

“…However these phenomena are to be explained, there seems to be little doubt (Baglioni, 3, to the contrary notwithstanding) that their mechanisms lie within the spinal levels and not far from the motor roots. Sherrington (30), Brown (7, 10), Forbes (14), Satake (29), Beritoff (4), Veszi (38), and Henkel (17) all emphasize this point. The last two investigators, on the basis of work with the strychninepoisoned cord, speak of an "autonomous" rhythm of the nerveganglion.…”

“…It should be mentioned, finally, that if the inhibition of nerve-impulse is due to interference, this inhibition would be chiefly manifested where nerve-impulses meet, i. e., at the synapses: and this would accord with Sherrington's view that the synapses are the seat of inhibition. There might be some question, too, as to how far the "fatigue" of synapses is an interference phenomenon (Forbes, like Sherrington, places fatigue at the synapses: 14).…”