THE PROCESSES OF DEPRESSION 251 



the foregoing experiments, the processes of disintegration can 

 continue to anoxydatively take place during narcosis, the prob- 

 lem arises, if this anoxydative breaking down can be further 

 increased by excitating stimuli. This question has been answered 

 likewise by means of experiments on the nerve made by Heaton. 1 

 The two sciatic nerves of the same frog were drawn through 

 a double glass chamber of the form previously described so that 

 each nerve lay on an electrode and with the central stump pro- 

 truding out of the chamber hanging likewise over an electrode. 

 As in the former instances the muscle contraction of the shank 

 again served as indicator. Both nerves were then subjected to 

 the same current of nitrogen-ether. When, as a result of the 

 narcosis, their irritability has sunk to the level of "stromschleifen" 

 the central stump of the one nerve was continuously stimulated 

 with faradic shocks during a prolonged period, while the other 

 nerve remained at rest. Finally, by displacement of the current 

 of nitrogen-ether with one of pure nitrogen, cessation of narcosis 

 was brought about. It was then seen that the irritability of the 

 continuously stimulated nerve showed a much greater decrease 

 than that of the nonstimulated. The control made by introduc- 

 tion of air demonstrated that both nerves recovered in an oxygen 

 supply. There can, therefore, be no doubt, by comparative exper- 

 iments we find, that during narcosis anoxydative disintegration 

 can be still further increased by the action of stimuli. 



In view of this knowledge of the influence of narcotics on 

 oxygen exchange it may be considered as a firmly established 

 fact, that a process of depression is developed during narcosis, 

 which can be classified with the large group of depressions, re- 

 sulting from deficiency of oxygen. This is followed by the impor- 

 tant problem, is it possible to attribute the whole series of altera- 

 tions, produced by the narcotic, solely to this one factor? In other 

 words, is narcosis the result of acute suppression of the oxyda- 

 tive processes? 



If the individual symptoms which characterize narcosis are 

 investigated from this point of view, one must indeed confess 

 that they are all readily understood when regarded as the results 



1 Heaton: 1. c. 



