632 CEREBRAL CONVOLUTIONS. [BOOK in. 



response; and though before the operation he became violently 

 excited when the laboratory servant dressed in a fantastic garb was 

 presented to him, he remains after the operation perfectly in- 

 different to the same image. Another striking character of this 

 imperfection of vision is that recovery from it to a considerable 

 extent is, under certain circumstances, possible by means of 

 educational exercise; the dog, which at first could not recognize 

 his food by sight and was indifferent to the whip, learns after 

 a while to know the one and to respect the other. It would 

 be hazardous however to insist upon the view that in such a case 

 the failure was of distinctly psychical origin, due to the want 

 of intelligent power to fully appreciate the crude sensations. It 

 might be that the sensations were themselves imperfect, and 

 unable to give rise to sufficiently definite perceptions, all things 

 possibly appearing to the dog as if seen through a gauze with 

 all their colours washed out. With such an imperfect vision a dog 

 might readily fail to recognize meat by sight and might easily 

 regard with unconcern any figure however fantastically dressed. 



According then to the views advocated by Goltz, barring some 

 possible difference in the extent to which the intellect or the 

 emotions are respectively affected according to the part of the 

 brain operated on, removal of the brain gives no evidence as to 

 any part of the mind (using that word in a wide sense) being 

 connected with any particular part of the cerebral cortex. 

 According to the views advocated by Munk, all the sensations 

 which form the basis of psychical activity, are very definitelv 

 associated with distinct areas of the convolutions; and nearly 

 all those, Ferrier and others, who have urged the doctrine of 

 localization of function in the cerebral cortex have been led to 

 entertain conceptions more or less similar to those of Munk. 

 The time is not yet ripe to decide dogmatically between these 

 conflicting views, though it appears to us that of the two, the 

 former one is the nearer the truth. All the more so since there 

 are some reasons for thinking that in these operations which appear 

 to be confined to the cortex and the white matter immediately 

 beneath this, damage is not unfrequently done to more central 

 parts of the brain, such as the corpora striata and optic thalami ; 

 and it is quite possible that where blindness becomes a prominent 

 symptom after these operations, the immediate cause of that blind- 

 ness is not in the cortex but in the optic thalami. 



But if we accept Goltz's conclusions there still remains at least 

 an apparent contradiction between these and the conclusions 

 we reached just now concerning the results of stimulation of the 

 surface ; but this we must leave for further inquiries to clear up. 



Before leaving the subject of the cerebral convolutions we wish 

 to call attention to certain remarkable results which have been 

 observed to follow upon stimulation of the cerebral cortex, under 

 various circumstances, more particularly in different stages of the 



