633 



fall out, because tlie eyes cannot give direction (o (he intended 

 movements and therefore it is comprehensible that the nncertaintv 

 of the gait augments. 



However on the other hand i( can be said that as the e(|uilibrium 

 in particular is only regulated by proprioceptive stimuli, disturbances 

 in gait will occur, when a part of those fall out, but the distur- 

 bances will be partially improved by the exteroceptive stimuli, 

 which by means of the eyes can convey their stimuli. 



The above mentioned is known, but it is most important, that 

 when to such a tabes patient, either with opened, or shut eyes, 

 contact is given through persons walking alongside of him, the gait 

 greatly improves, even so, that the ataxia nearly altogether disa|)pears. 



As such a patient is not supported, but as he has only contact 

 with persons walking alongside of him, I think it may be assumed 

 that the equilibrium sensation of the upper limbs is |)ut into action. 

 The equilibrium-sensation orientales itself along this new path, brings 

 in this way new afferent proprio-ceptive impulses towards the 

 central nervous system and therefore it can better control the move- 

 ments of the lower limbs. The equilibrium sensation of the arms, 

 in the tabes patient, thus takes over the function of the equilibrium 

 sensation of the lower limbs and trunk (this only of course when 

 the tabes is prcbent in the caudal part of the spinal cord), which 

 for a great part has disappeared. 



Therefore we can sa^' the following: 



a. a tabes patient walks b}' his eyes,- by the vestibular organ 

 and the rests of the equilibrium sensation of the trunk and the legs. 



b. if such a patient has contact-sensation with persons wal king- 

 alongside of him, then he moreover walks by the equilibrium sen- 

 sation of the arms. 



In case a he lacks afferent e(piilibrium inqmlses on a great scale 

 and therefore lie walks atactic, in case A the amount of these equi- 

 librium-impulses is very considerably augmented and the ataxia there- 

 fore is improved, nay it even has entirely or almost disappeared. 



If we have a patient suffering from a vestibular alfection, then we 

 see on the whole the same effect. 



In this sort of patients the central nervous system loo receives 

 the exteroceptive impulses by way of the eyes, and moreover the 

 proprioce|)tive ones of the trunk and the legs, tln-ough the posterior 

 roots of the spinal cord, but none or only paitially from the proprio- 

 ceptive ones of ilie vestilndar organ. 



The I'e.^ult of this is, Ihal the amount of etpiilibrium inqmlses is 

 not suflicient, therefore the patient walks atactic. 



