CHAPTER 10 



Biophysical Studies on 

 Nerve and Muscle 



I had dissected a frog . . . and had placed it upon a table on which there 

 was an electric machine . . . . I took up the scalpel and moved its point close 

 to one or the other of the crural nerves of the frog, while at the same time 

 one of my assistants elicited sparks from the electric machine .... Strong 

 contractions took place in every muscle of the limb, and at the very moment 

 when sparks appeared the animal was seized as it were with tetanus .... 

 (Luigi Galvani, anatomist, surgeon, and obstetrician; 1781.) 



This chapter presents an outline of some recent studies on nerve, and 

 shows how these are related to motion effected beyond the nerve endings by 

 excitable tissue in muscle. In the next chapter these facts are interpreted as 

 part of the enveloping concept of the human physical system. Then some 

 generalizations about this system are made which develop the framework in- 

 troduced in Chapter 1 and upon which the various parts of this book are 

 strung. 



First, however: What is the nature of the physical apparatus — nerve and 

 muscle? 



TRANSIENT BIOELECTRICS IN NERVE 



In Chapter 7 the rest-condition of tissue was shown to exhibit voltage dif- 

 ferences in living membranes between the points at which solute activities 

 differ — and even in normal bulk tissue (Chapter 8) if bioelectric currents are 

 driven through it. Transient, or sudden, changes in voltages or currents are 



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