674 Or THE FUNCTIONS OP THE NERVOUS SYSTEM. 



hair of the head, or tickling the chin, would occasion violent spasmodic actions 

 in them. Spontaneous convulsions of the palsied parts, which occurred at other 

 times, were more frequent and more powerful after the use of strychnia. On 

 the first return of voluntary power, the patient was enabled to restrain in some 

 measure the excited movements : but this required a distinct eifort of the will ; 

 and the first attempts to walk were curiously affected, by the persistence of the 

 susceptibility to excited involuntary movements. When he first attempted to 

 stand, the knees immediately became forcibly bent under him ; this action of 

 the legs being excited by contact of the soles with the ground. On the 95th 

 day this effect did not take place, until the patient had made a few steps ; the 

 legs then had a tendency to bend-up, a movement which he counteracted by 

 rubbing the surface of the belly ; this rubbing excited the extensors to action, 

 and the legs became extended with a jerk. A few more steps were then made; 

 the manoeuvre repeated, and so on. This susceptibility to involuntary move-- 

 ments from impressions on the soles, gradually diminished ; and on the 141st 

 day, the patient was able to walk about, supporting himself on the back of a 

 chair which he pushed before him; but his gait was unsteady, and much 

 resembled that of chorea. Sensation improved very slowly : it was on the 

 53d day that he first slightly perceived the heat of the metal plate. Now in 

 this case, the abolition of common sensation was not so complete as in the for- 

 mer instance ; but of the peculiar kind of impression, which was found most 

 efficacious in exciting reflex movements, no consciousness whatever was experienced. 

 Not less interesting was the circumstance, that convulsions could be readily ex- 

 cited by impressions on surfaces above the seat of injury : as, by pulling the 

 hair of the scalp, a sudden noise, and so on. This proves two important points : 

 first, that a lesion of the cord may be such as to intercept the transmission of 

 voluntary influence, and yet may allow the transmission of that reflected from 

 incident nerves. Secondly, that all influences from impressions on incident 

 nerves are diffused through the cord ; for, in the instance adduced, the reflected 

 influence was undoubtedly not made to deviate into the cord by the morbid con- 

 dition of that organ, but followed its natural course of diffusion, being rendered 

 manifest in this case by the convulsions which were excited, in consequence of 

 increased activity of the motor function of the cord. It is further interesting 

 to remark, that, in the foregoing case, the reflex actions were very feeble during 

 the first seven days, in comparison with their subsequent energy ; being limited 

 to slight movements of the feet, which could not always be excited by tickling 

 the soles. In another case of very similar character, it was three days after the 

 accident before any reflex actions could be produced. It is evident, then, that 

 the spinal cord must have been in a state of concussion, which prevented the 

 manifestation of its peculiar functions, so long as this effect lasted ; and it is 

 easy, therefore, to perceive, that a still more severe shock might permanently 

 destroy its power, so as to prevent the exhibition of any of the phenomena of 

 reflex action. 



709. So many cases of this kind have now occurred, that it may be consid- 

 ered as a demonstrated fact, that the Spinal Cord, or insulated portions of it, 

 may serve in Man, no less than in the lower animals, as the centre of very en- 

 ergetic reflex actions, when the Encephalic power which ordinarily operates 

 through it is suspended or destroyed, or when it is prevented from influencing 

 the Spinal nerves by such an injury to the Cord above their points of connection 

 with it, as prevents the transmission of nervous polarity : and it is further evi- 

 dent that these movements are not more dependent upon sensation, than they 

 are upon the will, since they may be excited without the consciousness of the 

 individual, even when this is fully directed to the part. 1 And we thus have 



1 The Author is informed by his friend Mr. Paget, that among the notes left by John 

 Hunter (which furnished some of the materials for the admirable Catalogue of the Pa- 



