THE LIFE AND WORKS OF BROWN-SEQUARD. 693 



The sensory transmission was thought to take place exclusively by the 

 posterior columns, motor transmission by the anterior columns. 



This was a very simple and clear doctrine, that appeared to be well 

 established. But in the sciences, especially in these that relate to life, 

 well-defined limitations of this kind are not often found. Brown- 

 Sequard reopened the whole question by his experiments, especially by 

 showing that the transmission of sensory impressions may take place 

 through the gray matter of the cord quite as well as or better than by 

 the posterior column. 



At the same time he investigated another idea that had been 

 casually referred to by the brothers Weber — that of inhibition; to 

 this Brown-Sequard returned again and again during thirty years, 

 giving to it immense developments. 



The statements of Brown-Sequard were at first received with some 

 distrust, as often happens with those who oppose generally accepted 

 ideas and dominant schools. The official professors of the universities 

 often have their course of instruction fixed and do not like to have the 

 trouble of changing their teaching. Brown finally triumphed, for he 

 pursued his experiments without relaxation, giving them increasing 

 variety and attraction of form. He found that a transverse section of 

 one-half of the cord caused a paralysis of movement on the same side 

 and a paralysis of sensation on the opposite side in regions which receive 

 their nerves from the part of the cord situated above the section. This 

 is what Brown calls a unilateral paralysis. The experimental fact 

 corresponded with various pathological observations made on man and 

 was of use in diagnosing certain lesions of the spinal cord. 



This was not all. The reflex power of the cord, almost abrogated at 

 the moment it is separated from the brain, afterwards gradually 

 increases and the section of the posterior columns is followed by 

 hyperesthesia. In a report read on the 21st of July, 1885, to the 

 Society of Biology, Broca confirmed the exactitude of these experiments, 

 causing a profound revolution in the doctrine of Bell. The discussion 

 continued, none the less heated and active, from 1850 to 1860, without, 

 however, causing Brown, whoever might contradict him, to have resort 

 to those personalities which too often envenom scientific discussions. 



A similar question of this sort, yet more complex, separated Brown- 

 Sequard aud Charcot in 1871. This was that of the central localiza- 

 tion of functions. The paradoxical mind of Brown Sequard was always 

 ready to raise objections to accepted theories. He gave three lectures 

 to the Boyal College of Physicians in London to show that there is no 

 relation between a given cerebral lesion and a concomitant paralysis. 

 The question is indeed a complex one, the simple relations which seem 

 so evident a priori being often contradicted by certain secondary effects 

 of a reflex nature, in which intervene some inhibitory symptoms. A 

 local lesion of the cord or brain may thus cause congestions and hemor- 



