22 



CHEMICAL MECHANISM 

 OF NERVOUS ACTION 



DAVID NACHMANSOHN, research associate, department of 



NEUROLOGY, COLLEGE OF PHYSICL^NS AND SURGEONS, 

 COLUMBIA UNIVERSITY 



r\ VIEW of the dominating role of the brain and of the 

 central nervous system in the body, the problem of the 

 mechanism of nervous action has always attracted general interest. 

 When, from Galvani's experiments it became clear that nerves generate 

 electricity, the news was received with great enthusiasm, not only 

 throughout the scientific world, but also among all educated people. 

 For more than a century the analysis of the electric changes constituted 

 the only means of studying nervous action. And yet, 150 years later, 

 Herbert S. Gasser, one of the leading electrophysiologists of our time, 

 compared the electric spikes to the ticks of the clock (5). Both are 

 only signs of activity in an underlying mechanism: "It follows then that 

 if spikes are but manifestations of activity in the inherent mechanism 

 of nerve fibers, the story of nerve is by no means told when the spikes 

 are described. We need to know something about the mechanism 

 which produces them — how it is maintained, its capacity for work, 

 and when and how the work is paid for." In spite of all the valuable 

 information obtained by the study of the physical aspect, knowledge 

 of the molecular changes, /. ^., of the chemical reactions involved, is 

 necessary for the understanding of the mechanism of nerve activity. 



The special function of the nervous system, which is tliat of 

 carrying messages from one distant point of the body to another, may 



335 



