6 14 THE POPULAR SCIENCE MONTHLY. 



be true — the one to which the anatomical arrangement and the physio- 

 logical experiments point — that each part of the brain has its own work 

 to do, a limited area of disease will interfere with the work of the part 

 diseased — will produce a loss or impairment of one function, and will 

 not affect all the powers. 



The following instance shows that pathology supports anatomy 

 and physiology, and that the localization of functions and memories is 

 no longer a matter of question among scientists : 



Not long ago a man was brought into Bellevue Hospital, in this 

 city, suffering from fever, headache, delirium, and stupor, which had 

 developed after a blow upon the head. In addition to these symptoms, 

 he had a paralysis of the muscles on the back of the fore-arm, so that 

 he could not raise his left hand. The general symptoms indicated the 

 presence of an abscess in the brain. To the surgeon, familiar with the 

 anatomy and with the physiological experiments upon animals, the 

 paralysis of the arm-muscles indicated that the abscess was situated in 

 that part of the brain whose function it was to raise the hand. He 

 therefore sawed through the skull over the supposed site of the ab- 

 scess, and, although the hole which he made was only large enough to 

 admit his little finger, the abscess was found lying just beneath it, and 

 was emptied. 



Such a case shows that the study of localization may aid in saving 

 life. The following cases of loss of a definite kind of memory, occur- 

 ring suddenly, and accompanied by symptoms which indicated the sit- 

 uation of the disease in the brain, remind one very forcibly of the 

 physiological experiments described, and afford positive proof that 

 powers of sensation and memory, as well as the power of motion, may 

 depend upon the integrity of definite regions of the brain : 



An intelligent gentleman, while playing billiards, suddenly became 

 aware of the fact that he could see but one half of the ball at which 

 he was aiming. He had become blind in the right half of both eyes. 

 Soon after, on attempting to read, he found, much to his surprise, that 

 he could not read. He could see the letters and words, but they con- 

 veyed no meaning to his mind, and appeared to him as so many forms 

 — ^just as a set of Chinese letters do to us. He had lost the power to 

 recognize written and printed language. Singularly enough, he could 

 write as well as ever, but it was impossible for him to read what he 

 had just written. The memory of the motion involved in producing a 

 letter remained, the memory of its appearance was gone. The memory 

 of the motion served to take the place to some degree of the lost mem- 

 ory-pictures, for, when asked to read a word, he would bring up bis 

 hand to the page and with his finger trace the form of the letter, and 

 then name it. It was evident that the only means he had of recalling 

 a letter was by going through the motion necessary to write it — in 

 other words, by calling into play his motor-memories. As he was 

 more accustomed to trace written than printed letters, it took him a 



