Anatomy. — "Experimental cerebellar-atactic phenomena in diseases 

 lying extra-cerebellar'. By D. J. Hulshoff Pol. (Communicated 

 by Prof. Winkler). 



(Communicated in the meeting of March 23, 1918). 



In a previous communication^) I pointed out that our equilibi-ium- 

 organ has not to be exclusively looked for in the vestibular organ 

 as GoLTZ °) writes, and wishes, but that tiiis organ has its arborisations 

 through the whole of the body and that the vestibular apparatus 

 has to be considered only as a subdivision of it. 



The equilibrium tracts, which i-un centripetalwards as tracts of 

 Flfx'Hsig and Gowrr, possess exactly the same function as those 

 fibres of the vestibular apparatus, which too provide for our equilibrium. 



Further investigations ') then taught me, that sensory cerebellar 

 ataxia must take place, when the above-mentioned afferent tracts in 

 their course through the cerebellum, are damaged. 



Should this supposition be true, then from it can be deduced, 

 that cerebellar ataxia can be called forth by interruption of these 

 afferent paths, before they reach the cerebellum. 



I therefore put before me the question, whether it should be 

 possible to provoke cerebellar ataxia, l""' by interrupting totally or 

 partially the afferent tracts, which conduct from the mednlla spinalis 

 towards the cerebellum, before they reach the corpus restiforme, 

 and 2"^' io injure more or less the vestibular nerve, before it arrives 

 within the dura. 



In reference to the former, a transsection distally from the resti- 

 form body is necessary, because in it also other fibres are found, 

 which do not originate from the medulla spinalis. In reference to 

 the lattei-, destroying of the vestibulai- fibres is necessary before they 

 arrive within the scull, because the injuries due to the operation, 

 within the scull, might provoke a matter of complications less 

 wished for. 



') On our equilibrium-organ. Verslag Kon. Akad. v. Wet. Nov. 1917. 

 3) See H. Zwaardemaker, Physiology. 11 Vol. p 286. 



3) Cerebellar ataxia as disturbance of the ec[uilibrium sensation. Verslag. Kon 

 Ak. van Wet. Jan. 1918. 



71 

 Proceedings Royal Acad. Amsterdam. Vol. XXI. 



