CHAPTER XV 



THE PHYSICO-CHEMICAL BASIS OF TRANSMISSION 

 IN NERVE AND OTHER PROTOPLASMIC - 



SYSTEMS 



The view that the transmission of the excitation- 

 state from the active region of an irritable protoplasmic 

 element to the adjacent resting region is the result of 

 secondary electric stimulation by the local bioelectric 

 current between the two areas is one which is supported 

 by general theoretical considerations and by a variety 

 of direct and indirect evidence. In a general sense there 

 is nothing novel about this hypothesis, which, like most 

 scientific conceptions, has had its historical background 

 and development; it was expressed tentatively by Du 

 Bois-Reymond^ and in a more definite form by Hermann;'' 

 more recently Kiihne, Cremer, Gotch, Keith Lucas, 

 and others have supported it on various grounds.^ The 

 absence in nerve of any observable accompaniment of 

 the local excitation process, other than the electric 

 variation, which could conceivably serve as a stimulus 

 to the resting region adjoining the active area, is in 



^ Gesammelte Ahhandlungen ztir allgemeinen Musket und Nerven- 

 physik, II, p. 698; cf. p. 733. 



2 See especially the clear statement by Hermann in his Handbuch, 

 II, 194, cited in Cremer's comprehensive article on nerve physiology in 

 Nagel's Handbuch der Physiologie, IV, 2d half (1909), 929. 



3 Kiihne, Croonian Lecture, Proceedings of the Royal Society, XLIV 

 (1888), 446; Cremer, loc. cit.; Gotch, article on nerve in Schafer's text- 

 book, cf. pp. 458, 557 ff.; Keith Lucas, Journal of Physiology, XXXIX 

 (1909), 207. 



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