Fatigue of Excitation and Fatigue of Depression etc. 55 



probability of undiminished intensity (italics mine), tend to be blocked 

 in the passage from nerve to muscle." 



Is it too much to say that only the caution of deference to the 

 old, old idea of susceptibility of the central nervous system to fatigue 

 is the main restraining factor in the way of leaving it entirely out 

 of account? One is led to feel that in the ideas that have resulted 

 from Weichardt's (1904) claim of the discovery of a specific toxin 

 of fatigue. It becomes a question of immunity! Thus Stadlinger (1908) 

 says: ". . . . es konnte keinem Zweifel mehr unterliegen, class ,Er- 

 müdung' und ,Erholimg' zum grossen Teile auf einer Wechselwirkung 

 von Ermüdungstoxin und Ermüdungsantitoxin beruhen." The endurance 

 from training rests upon the development of a power of resistance 

 to the toxic fatigue substances, in other words, an immunity. Then 

 where does the cell come in, with its functional growth and over- 

 growth? Let us come back to it. Far be it from me to deny the 

 existence even of very specific fatigue by-products or that the body 

 is perfectly capable of neutralizing them and of increasing that 

 power. Still, is it strange that when in analogy with true immunity 

 the power should have reached its height, from weeks and months 

 of accustomance, there occurs the "nervous prostration" and the 

 athlete goes stale? 



The proof of the nerve cell's exhaustibility must be anatomical, 

 being a matter of the unit, and is conclusively afforded. For the 

 details of the development of this proof the reader is referred to its 

 appropriate place of discussion. Here only certain salient features 

 will be mentioned and the discussion will be devoted mainly to the 

 reasons for the lack of appreciation from the physiological side. No 

 other evidence of the exhaustibility is really needed other than that 

 the process of activity ends with an absolute dechromatinizatioii of 

 the cell. By this is meant not merely the total consumption of the 

 Nissl substance, extra-nuclear functioning nuclear material though it 

 be instead of a food material as by some lowly estimated. The 

 chromatin of the nucleus, chromatin in its strictest, most conventional 

 sense, disappears from the nucleus as the last phase of activity. No 

 one could deny that this represents a climax of organic disturbance 



