326 POPULAR SCIENCE MONTHLY. 



powerless area from the other cortical areas, which were under excite- 

 ment. 



Now we know with certainty that increased intensity of the 

 stimulation is followed by increased area of neural excitement. A 

 spreading of the nervous processes on which the initiation of motor 

 impulses depends — whatever the chemico-physical character of those 

 processes may be — would, then, necessarily take place in the center 

 of the N. facialis, in answer to the increased demands made upon it 

 by the more intense stimulation from various higher areas. This 

 spreading would, it is likely, have the double effect of enabling the 

 center to use hitherto unused paths between itself and the center of 

 the accessory nerve; and it might also compel the immature nerve- 

 elements to myelinate themselves in preparation for the discharge of 

 their new functions. When this enlarging area occupied, during its 

 excitement, by the center of the facial nerve, had broken over, so to 

 say, into the center of the accessory nerve, and had made good and 

 useful the newly established connection between the two, then it could 

 virtually resume its old functions of control, although now by a new 

 and more roundabout path. 



The assumptions previous to the last would all seem to be helpful, 

 if not needful, to explain some of the features of this case of nerve- 

 anastomosis and sequent recovery from facial paralysis. The last as- 

 sumption is absolutely essential in order to make any satisfactory 

 progress toward explaining it at all. The other assumptions very 

 speedily bring us to the hitherto impenetrable veil of mystery which 

 is met when any attempt is made to explain the facts of experience by 

 our theories of cerebral physiology or of experimental and physio- 

 logical psychology. But the last assumption seems somewhat to 

 lengthen the distance to the veil. The picture of the unity in variety 

 of the histological elements, and collections of elements, and of the 

 physiological functions, which belong to the nervous system, offered by 

 such experiences as that of this patient, assists in confirming the views 

 arrived at experimentally by Professor Sherrington and other ex- 

 plorers in this field. But the unity and the variety of this infinitely 

 complex system are not so much matters of wholly predetermined 

 and, so to say, ' made-up ' sort, dependent upon unchangeable 

 histological peculiarities externally combined into a whole; they are, 

 the rather, a growth, changeful, adaptable to varying conditions, de- 

 pendent upon need and use, and conditioned' chiefly, if not wholly, upon 

 the possibility of establishing the necessary connections amongst the 

 differently located elements. 



Many of the more important and interesting problems of psychology 

 are suggested by this case of anastomosis. No other group of muscles 

 is so expressive, so responsive to ideas and emotions, as those which 



