Vestibular compensation 

Scientists were persuaded to destroy common truths and acknowledged authorities in science by Maxwell. I paid a huge price for such a conduct but I did not fear to do it in the name of progress. This time it concerns vestibular compensation, which so far has been considered the most important phenomenon in the field of the clinical otoneurology.

According to my discoveries of the principles of operation of the vestibulocerebellar system, the term "vestibular "compensation" does not have its raison d’être in the clinical otoneurology. All hallmarks of vestibular compensation completely exhaust the phenomenon of vestibular habituation. This should complete the description of this phenomenon. Yet I will come back to the textbook to which I was sent back several times. I was constantly instructed that all problems which I had been dealing with had already been well explained in this textbook. The evidence to prove that nothing has ever been explained may be provided by several quotations from the chapter "Vestibular compensation" edited by Bień (1) - quotation: -"Summing up the above mentioned results it can be concluded that after the compensation of the unilateral destruction of the vestibular organ, the approximate compensation of the functional activity of both complexes of vestibular nuclei occurs on the level which is clearly lowered in relation to the norm. Regardless of retuning the activity of the vestibular nuclei for full compensation of the reflexive functions there must exist a number of structures of the central nervous system, producing a new model of integration of stimuli from the remaining receptors participating in controlling the equilibrium and the stabilization of the field of vision".

quotation: "Trying to to explain the processes occurring during vestibular compensation, Magnus (1924) put forward a hypothesis that during this process there occurs formation of new complexes of synaptic connections within the structures of the central nervous system responsible for maintaining the equilibrium".

quotation: There remains Precht's pure academic discussion (46) whether in the process of compensation the leading role should be credited to the "reorganization" of the structures in the central nervous system (first of all in the vestibular nuclei) or to widely understood mechanisms of "substitution" on the part of the remaining two senses - the sight and the proprioception".

quotation: "It may seem paradoxical but although the issue of vestibular compensation is one of the key issues of the clinical otoneurology, our information in this range is less exact from that concerning experiments on laboratoty animals. In the clinical practice it is difficult to find a proper model, which could be used for tracing the vestibular compensation process without participation of numerous additional determinants, such as age, co-existing illnesses, the influence of medicines, emotional determinants, etc.".

quotation: "The slow changes taking place in the chronic phase are characterized, on one hand, with a variable level of the central inhibition of the vestibular nuclei complex and on the other hand, compensation (recruitment) within the complex of the nuclei in the damaged side. Therefore, a measurable exponent of compensation in this period will be the assessment of the degree of inhibition (the absolute values of the reaction) in induced tests and the assessment of the directional predominance in these tests".

quotation: "Bechterew’s phenomenon is also indirectly associated with the phenomenon of overcompensation and the so-called recovery nystagmus (Erholungsnystagmus) which consists in the appearance of nystagmus or (in a more subtle form) the directional predominance of induced reactions towards the damaged labyrinth, after the period of partial compensation of the ensuing damage. At present there is a conformity of views with the opinion of Stenger (56), who claims that this process results from a partial or an entire restoration of the function in the damaged vestibular receptor. While summing up the restoration of the receptor activity and the increased during compensation activity of the vestibular nuclei complex on that side, there occurs a functional predominance of the side with the damage. However, because it is difficult to produce an experimental model of such a damage, there is lack of detailed research into this form of vestibular disturbances".

REFERENCES

1. Bień S.:  Vestibular compensation. Texbook "Clinical Otoneurology" ed. by G. Janczewski. Warsaw 1986. PZWL