SUGGESTIVE CASE OF NERVE-ANASTOMOSIS. 323 



Fig. 7. 



supplied properly by the spinal accessory. Following this in a few 

 weeks there is some power of volitional movement in the paralyzed 

 muscles of the face, without association of shoulder movements. Last 

 of all comes — if it comes at all — the emotional movements over which 

 the patient has no conscious volitional control." 



This case which I have now presented in barest outline (and all 

 similar cases of recovery of voluntary and emotional control of 

 paralyzed muscles after anastomosis) raises a number of questions 

 of interest to students both of cerebral physiology and of psychology 

 from the physiological and experimental points of view. Among these 

 the chief is, perhaps, the problem as to what takes place in the 

 cortical centers that is brought about by the changes in the peripheral 

 tracts through which the centers control the different groups of 

 muscles. No completely satisfactory answer to this problem seems at 

 present to be anywhere in sight. But there are three or four tenable 

 hypotheses which may — probably with at least some factors taken from 

 each — contribute toward the better understanding of the problem. 



Of such hypotheses the first which I will mention suggests that a 

 more or less nearly complete substitution of function took place be- 

 tween the center of the N. facialis and that of the N. accessorius. 

 Their proximity would be favorable to this — the two centers being 

 not more than about one inch apart. That the cortical center of the 

 accessory nerve did exercise some control over the facial muscles 

 through the united accessory and facial nerves is apparent from the 

 effect produced upon those muscles by raising the arm or shrugging 

 the shoulder. With the general fact of a certain power of substitution 

 of new cerebral areas for disused or injured ones, cerebral physiology is 

 familiar. But how centers so unlike in the character and variety of the 

 muscular functions which they control as are the center for the facial 

 muscles and the center for the trapezius muscle could substitute for 

 each other, is difficult to imagine. Inasmuch, however, as the cortical 



