564 THE POPULAR SCIENCE MONTHLY 



The constant and urgent request of the patient for relief, at all 

 risks, from his distressing condition, induced the doctors to attempt 

 the fourth operation; and when this was unsuccessful even to the ex- 

 tent of revealing the abnormal conditions, to the fifth operation, which 

 was without anesthetics and which is the one chiefly interesting from 

 the psychological point of view. 



This fifth operation was performed March 26, 1907. The bone 

 flap was for the fifth time reflected; the dura was incised some dis- 

 tance outside the largest previous incision; an incision was made into 

 the gyrus centralis posterior, which appeared somewhat flattened and 

 yellowish in color; and about one centimeter below the surface the top 

 of a thin-walled cyst came into view. By enlarging the incision until 

 it measured 5 centimeters this cyst was removed; but below it a still 

 larger cyst was disclosed, which was " in turn shelled out of its bed 

 by pushing the brain away from it, and was in this way removed un- 

 ruptured." The entire procedure lasted about three hours. 



But what about the mental condition of the patient during this 

 long-continued and extensive exploration and cutting and pulling of 

 the brain and its integuments ? We are informed that he was " in- 

 terested," asking questions and conversing with the doctors most of 

 the time. Although perfectly conscious, he "experienced no sensory 

 impressions whatever, even when the dura was incised." The only 

 discomfort, not to say pain, given to him by these extensive explora- 

 tions of his brain, was when the edge of the incision of the dura was 

 caught in a clamp and the membrane dragged upon. The patient 

 himself called the attention of the surgeons to an otherwise unnoticed 

 phenomenon which consisted of a slight twitching of the muscles of 

 the left side and shoulder. 



In his report Dr. Gushing expresses his regret that this rare op- 

 portunity was not seized in order to test the effects of stimulating the 

 posterior and post-central convolutions upon the experience of con- 

 scious sensation. In a subsequent case of cerebral surgery without 

 anesthetics, however, these convolutions were stimulated and distinct 

 impressions of sensations were obtained which were localized by the 

 subject in the extremities and not at all in the cortex itself.^ No such 

 sensory impressions were obtained by stimulating the pre-central area, 

 or " motor strip," although the customary motor results were obtained. 

 Further details of the second case were not at my disposal at the time 

 of writing this paper. 



The following remarks upon these surgical results as viewed from 

 the psychological point of standing are intended as suggestions rather 

 than as definitely established conclusions. 



^ Still more recently, as I have learned in conversation, in a third case of 

 cerebral surgery without anesthetics, the same operator obtained similar resulta 

 of conscious sensations by faradizing the same region of the cerebral surface. 



