Die kleine Nystagmusschrift und Hypoxie der vestibul�ren Zentren

[Investigation of the influence of vigilance on the nystagmic reaction (author's transl)]

A modification of mental arithmetic (MMA) combined with a key press technique was used to raise the patient's level of vigilance during routine investigation of vestibular function. The effect of MMA is studied by comparing succeeding pendular tests under different conditions. Group I: 81 patients had the first pendular test without and the second with MMA. Control group II: 31 patients had the tests in opposite order. The nystagmograms were analysed by computer. The application of the MMA-method resulted in a significantly increased average reaction intensity with differences up to 20% and more, according to the considered nystagmus parameter. This effect does not depend on the chronological order of the tests with or without MMA. On the other hand, in both groups a higher level of vigilance is correlated with less nystagmic beats (5-8%). Therefore, the number of beats does not show the characteristics of typical intensity parameters. The comparison of the absolute values of the analysed parameters shows good reproducibility of the average results under identical circumstances. In the last 4 years the MMA-method turned out to be easily applicable. For all these reasons, this method was included into the routine examination of vestibular system function to raise and keep constant the level of vigilance.

Effects of adenosine diphosphate administration on the vestibulo-oculomotor reflex of rabbits

Adenosine diphosphate (ADP) injection into a unilateral vertebral artery in rabbits decreased per-rotational nystagmus; the nystagmus beating toward the injected side was predominantly suppressed. This influence became obvious when the animal's blood pressure was low. Field potentials were recorded in the vestibular nuclei upon electric stimulation of the vestibular labyrinth. ADP administration into the vertebral artery also suppressed the amplitude of vestibular evoked potentials (VEPs). Effects of ADP upon the vestibulo-ocular reflex and VEP were considered to be due to regional ischemia induced by the microemboli, which consisted of platelet aggregation.

[Irritation of vestibular center and "ecriture centrale" (author's transl)]

To confirm the value of the écriture centrale during the pendular test clinical and animal experiments were performed. The écriture centrale was recorded in 12% of 710 subjects otoneurologically examined, mainly in groups with commotio or contusio cerebri, diseases of the brain and vertebrobasilar insufficiency. Also écriture centrale was a sign of functional disturbacne after lumbar occiptal puncture without organic lesion and in boxers. In six rabbits écriture centrale was observed after occipital puncture.