XXVI. THE NERVOUS SYSTFM (continued). 

 Function. 



From the nervous system we gain control of the 

 organs of the body, and to its action we owe our 

 power to adjust ourselves to our surroundings in general 

 and to maintain relations with other human beings and 

 objects. In securing to us this adjustment to our envi- 

 ronment, the nervous system manifests many forms of 

 activity. For example, the interconnection of the fibers 

 permits the transmission of messages of control and super- 

 vision. The end organs of various forms give rise to 

 special kinds of impulses, and when these are transmitted 

 to the centers, the structures found there are able to trans- 

 late them into sensations and thus furnish information 

 in regard to our surroundings which is of vital importance 

 in determining the character of the control impulses. 

 Finally, the nerve centers are the origin of those mental 

 operations which we call will, emotion, thought, etc. 

 In short, the verj^ individuality of a man is a function of 

 his nervous S3'stem. 



The explanation of the many actions which we group 

 under the common name of mind activities is properly 

 the province of a science called psychology. In the study 

 of the physiology of nerve action we are concerned only 

 with the changes which take place in the nervous ele- 

 ments of structure in giving rise to these operations and 

 the manner in which these changes occur. Owing to the 



411 



