Chapter XI 



NERVOUS INTEGRATIONS IN MAN 



J. F. Fulton and C. S. Sherrington 



IT has to be remembered that of the cells, which in their 

 multitudes compose the body, whether animal or 

 human, each one leads its individual Hfe, is individually 

 born, feeds and breathes for itself, and is destined for 

 individual death. This book has described already these 

 microscopic hving units, and their arrangement and com- 

 bination into differentiated systems and aggregates called 

 tissues and organs. These pages have also told how from those 

 systems and organs is constructed the unified individual, 

 for instance the human being. With the differentiation of the 

 cell systems have gone division of labor and specialization 

 of function, and a crowning part in the integration of the 

 total individual is played by the system of differentiated 

 nerve cells, the nervous system. 



NERVOUS integration 



The system provides speedy communication between one 

 part of the body and another part, by message sending. 

 One of its main offices is to "operate" the muscles. It has 

 been commonly and permissibly hkened to an electric 

 installation with connected central exchanges whither run 

 wires from receiving stations and whence issue wires to 

 outlying motor machines. Through it a single receiving 

 station has touch with many of the motor machines. The 

 exchanges are the nerve centers in spinal cord and brain; 

 the motor machines are the muscles, the receiving stations 

 are the sense organs, and the wires are the nerve fibers 

 connecting all these into a system. The central exchanges 

 are so contrived that a wire from a receiving station can 

 put these or those motor machines into action and likewise 

 stop or restrain others which would impede or conflict with 

 them. 



The receiving stations are commonly called sense organs; 

 through them light, sound, or other external stimuh excite 



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