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[Migraine and the vestibular apparatus (author's transl)].

Thirty patients with simple or ophthalmic migraine had an otoneurological examination. 13% complained of vertigo during attacks of migraine, 17% of giddiness and 6.7% of tinnitus. The usual tests for equilibrium were normal. On electronystagmographical examination 17% of the patients showed only pathological spontaneous nystagmus, 33% only disturbances of caloric response and 7% a combination of both. Audiological testing was normal. The incidence of vestibular disturbances, particularly sensitivity differences of the labyrinths, was significantly greater in the group of patients with migraine than in a control group of 30 healthy persons (P less than or equal to 0.025). On the average, the sensitivity differences, in terms of duration of reactive nystagmus, were greater for these than for the healthy persons (P less than or equal to 0.01). Patients with vestibular disturbances did not show a greater frequency of pathological EEG readings than patients with normal vestibular function. Some hypotheses concerning the pathogenesis of vestibular symptoms as found in migrainous patients are mentioned.

Adult↗

[Ultrastructural changes in the receptor portion of the vestibular apparatus in response to noise].

The experiments have been performed on 24 guinea pigs (48 labyrinthes), 6 of them--control and 18 have been subjected to noise (one octava) with the average geometrical in diaposone of 2,000 Hz, at intensity level 100 dB. Six animals are subjected to a single effect for 6 h and 12--to repeated effect during 6 days running, 4-6 h daily. Isolation of both the vestibular and the cochlear parts of the membranous labyrinth is performed simultaneously. This gives a possibility to study all the receptors of the internal ear as a whole. Certain ultrastructural changes in all the vestibular receptors both at a single and repeated effects are revealed. Dilatation of the granular endoplasmic reticulum is observed, situating mainly in the basal part of the cell; swelling of mitochondria is accompanied with a sharp clearance of their matrix. In some mitochondria there is a local destruction of their external and internal membranes. Moreover, in cytoplasm of the receptory cells sharply osmiophilic fibrillar structures are revealed, they resemble crists and are arranged in bundles. In some cells they are not numerous and localize mainly in mitochondria, in others--their number is greater, and they localize not only in mitochondria, but in the surrounding cytoplasm, too. Similar structures are observed in some preganglionic myelin fibers. These phenomena can be considered as development of calcification processes. The changes described, evidently, form the basis of the vestibular disorders under the noise effect.

Animals↗

[The behavior of sensory and ganglia cells of the vestibular apparatus of the guinea pig in response to inadequate stimulations].

The behaviour of the sensory- and the ganglia cells in response to inadequate stimuli was studied at 12 adult guinea pigs. The sensory cells of the three Cristae ampullares dont respond remarkably to acoustic stimulation. At the range of 1000 Hz a recognizable increase in the size of the sensory cells at the upper ampulle was noticed. Of no account was the rest of the volume variations. At the range of 5000 Hz the sensory cells of the Maculae staticae responded with a considerable increase in the size of their sensory nuclei up to 38%. The cells of the Ganglion vestibulare react upon acoustic stimulation throughout with an increase in their nuclei up to between 16% and 54%. It was noticed that the volume enlargement increases from the lower to the higher frequencys. The cells of the Ganglion geniculi nervi facialis react upon acoustic impulses too with an increase in their nuclear volume. In low tone acoustic range and in high tone acoustic range the growth rates are more than 50% beyond the standard. Thos cells respond to frequency of 1000 Hz remarkably intensive. It was noticed that the maximum volume increase of their nuclei was in the average up to 103%. All the sensory and ganglia cells react upon rinsing the external auditory canal with 12 degrees C water, with a shrinkage of their nuclei. Besides that the sensory cells of the Cristae and the Maculae show a volume decrease between 8% and 19%. The cells of the Ganglion vestibulare et geniculi respond with a considerable volume decrease of their nuclei from 32 to 41% under the average.

Acoustic Maculae↗

Does the vestibular apparatus play a role in the development of the visual system?

1. The receptive field properties of visual cortical neurones were investigated in kittens that had been subjected to either unilateral or bilateral labyrinthectomy shortly after birth.2. Two kittens were reared in a normal visual environment. Another two were reared in the dark with recurrent exposures to vertically oriented black and white stripes, which in normal kittens is known to bias the distribution of receptive field orientations.3. For both normally reared and stripe-reared labyrinthectomized kittens, no differences were detected in cell types, preferred orientations, binocularity, columnar organization, or any other neuronal properties, compared with similarly reared intact kittens.4. The failure to detect deficits in visual development after labyrinthectomy is discussed in relation to other reports of vestibular influences on the visual system of the adult cat.

Journal Article↗