CHAPTER V 



THE ANALYSIS OF THE PROCESS OF EXCITATION 



Contents: Indicators for the investigation of the process of excitation. 

 Latent period. The question of the existence of assimilatory excita- 

 tions. Dissimilatory excitations. Excitations of the partial compo- 

 nents of functional metabolism. Production of energy in the chemi- 

 cal splitting up processes. Oxydative and anoxydative disintegration. 

 Theory of oxydative disintegration. Dependence of irritability on 

 oxygen. Experiments on unicellular organisms, nerve centers and 

 nerve fibers. Restitution after disintegration by metabolic self- 

 regulation. Organic reserve supplies of the cell. The question of a 

 reserve supply of oxygen of the cell. Metabolic self-regulation as a 

 form of the law of mass effect, and metabolic equilibrium as a con- 

 dition of chemical equilibrium. Functional hypertrophy. 



If it is true that all primary effects of stimulation consist either 

 in an excitation or depression of the metabolism, and that all other 

 effects of stimulation secondarily follow this primary alteration 

 of the metabolism of rest, then every thorough analysis of the 

 mechanics of reaction must have its beginning in the investiga- 

 tion of these primary processes. I desire to adopt this method 

 here and will analyze somewhat further the primary process of 

 excitation and its immediate and remote sequences. This will be 

 followed later by the analysis of the process of primary depres- 

 sion and its results. 



The investigation of the more obscure processes in the living 

 substance places us in a difficult position, for their details cannot 

 be observed by the unaided senses. That which we can perceive 

 is merely the grosser vital action, consisting of a complex combi- 

 nation of the individual processes, the total result of a multitude 

 of different components. For this reason the conception of exci- 

 tation can only be established by observations based upon the 

 combined vital actions, which are produced by the effect of stimu- 



