848 



THE SPINAL CORD. 



dystrophy," l due to the permanent withdrawal from the spinal cells of 

 influences they are normally accustomed to receive from other portions 

 of the central nervous system. The most favourable time for the 

 examination of the independent capabilities of the spinal cord is that 

 when the sum of " shock " and " isolation-dystrophy " together is of 

 smallest amount. That time, compounded as it is of two such variable 

 factors, is itself extraordinary variable. In the monkey, " shock " lasts 

 longer and the "isolation dystrophy" comes on earlier than in other 

 animals commonly observed in the laboratory. It is the conjunction of 

 the periods of these two phenomena which I imagine renders so difficult 

 and so largely defeats attempts at observations of the proper spinal 

 reactions of the monkey. If the overlap of the two is great, then no 

 spinal reflexes or only the merest traces of them may be elicitable. In 

 man it is natural to suppose that even more than in the monkey will 

 spinal " shock " be severe and " isolation dystrophy " arrive speedily. 

 Clinical observation supports and confirms this supposition. 2 After 

 total transverse lesions of the cord in man, the depression of function 

 of the skeletal musculature is profound and practically permanent. On 

 the other hand, the depression of visceral function seems hardly greater 

 in man and the ape than in the rabbit and frog. 



By his sense organs and their nerves the individual is put en rapport with 

 the material universe. His sense organs constitute between his mind and that 

 universe the only go-between. That universe for each individual is made up 

 of two portions, one a part beyond his body, termed his environment, the other 

 a part consisting of his own body, or more strictly of all that part of it that 

 can affect his afferent end-organs. This latter part constitutes his " material 

 me." It is divisible. Taking its sensibility as basis for its subdivision, it 

 is a compound of skin, of motor apparatus, and of viscera. With the first 

 of these are concerned perceptions obtained through the projecting as well 

 as through the non-projecting senses. The senses concerned with the motor 

 and visceral apparatus are solely non-projecting. The higher nervous centres 

 are built, especially where most perfected, on the projecting senses far more 

 than on the non-projecting. Of the non-projecting, the muscular much more 

 closely than the visceral is linked with the powers of the great motor organ, 

 the skeletal musculature, itself arisen chiefly as a machine for reacting to the 

 projicient senses. Hence comes it that after destruction of the higher nervous 

 centres, e.g. brain, the competence remaining to the spinal centres is found greatest 

 for visceral reactions. From this point of view the visceral reflexes present the 

 most perfect nervous reactions of the spinal animal. The bulbo-spinal animal, 

 receiving as it does the afferent impulses of the vagus as well as of the thoracic 

 and sacral nerves, may indeed be considered, as regards visceral function, a 

 fairly perfect animal. The purely spinal animal does, however, exhibit some 

 amount of damage to the nervous regulation of its viscera ; this is chiefly of 

 the nature of " shock," and temporary. The visceral shock appears to be little 

 if at all greater in the ape and man than in the rabbit and frog, whereas in the 

 two former the shock to the spinal mechanisms of the skeletal musculature 

 is enormously greater than in the two latter types. The significance of the 

 deeper depression of reaction into which the higher animal, as contrasted with 

 the lower, sinks when made " spinal," appears this, that in the higher types 

 more than in the lower the great projecting senses actuate the motor organ, 

 and impel the motions of the individual. The deeper depression shows that 

 as the individual ascends the scale of being, the more cognisant does it become 

 of a circumambient universe that is "not me," and that that latter acquires a 



1 Sherrington, Phil. Trans., London, 1897. 



2 Bastiau, Med.-Chir. Trans., London, 1891 ; Bruns, Neural. CentralbL, Leipzig, 1893. 



