28 STUDIES ON THE CENTRAL NERVOUS SYSTEM 



nerves in man and studied their recovery. We have seen 

 many of the facts described by Head. Om- investigations 

 however, did not convince us, that the theory of the existence 

 of two distinct pathways for protopathic and epicritic 

 sensibility has yet been proved. But we felt that this work 

 is a great advance in science, especially because phylogeneti- 

 cal ideas have been introduced into the doctrine of clinical 

 sensibility and that autonomic sensibility has been brought 

 to the foreground. Protopathic sensibility namely, is the 

 primitive form of peripheral sensibility and must be very 

 old in phylogenesis. Epicritic sensibility is a higher and 

 more complex form and develops later. In Head's opinion 

 protopathic sensibility is closely connected with centripetal 

 sympathetic fibres. 



In discussing the autonomic nervous system many 

 physiologists and neurologists consider only the centrifugal 

 side, that is, they speak about the sympathetic nervous 

 system in so far as it has been analysed by Langley. But in 

 my opinion, this is too narrow. We know there are also 

 many sympathetic fibres, for instance, in the intestines, 

 which send impulses in the direction of the central nervous 

 system. This is also the case in the vagus, which belongs to 

 the parasympathetic system of Langley. We are aware 

 that many stimuli from the lungs, the larynx etc. are sent 

 to the brain along this nerve. 



It is true, that this centripetal side of the autonomic 

 nervous system has not been so clearly analysed as was the 

 centrifugal by Gaskell, Langley and others. But still we 

 know sufficient facts to work with in physiology and in 

 clinical examination. Huber has proved that in the walls of 

 the blood vessels there are many unmedullated sensory fibres. 

 When stimulated by pinching the blood vessels during an 

 operation under local anaesthesia, severe pain is often felt by 

 the patients. Recently Leriche and Tournay in France 

 have shown that sensory impulses may indeed be conducted 

 by sympathetic fibres. 



