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Presentation of a posturographic test with loading of the proprioceptive system

Postural control is maintained by sensory feedback from visual, vestibular and somatosensory receptors. Recently several methods for evaluating postural control have been devised, utilizing an imposed perturbation. Most of these methods use stimuli which simultaneously affect more than one of the sensory feedback loops. In the present paper a posturographic technique is presented with specific loa

Clinical aspects of eye tracking test

The eye tracking test is today a well established part of clinical otoneurological examination. In the present paper some applications of the test in evaluating of the level of lesion within the vestibular system are reviewed.

Pharmacological treatment of vertigo

A review of the treatment of vestibular disorders with drugs is presented. In animal experiments, administration of certain drugs, e.g. alcohol, barbiturates and chlorpromazine, retards the vestibular compensation, while others, e.g. caffeine, amphetamine and ACTH, accelerate the compensation. In compensated animals, some drugs produce overcompensation and some decompensation. A double-blind, rand

Evaluation of optokinetic nystagmus in differentiating between peripheral vestibular and infratentorial lesions

Optokinetic nystagmus (OKN) was studied in ten patients with vestibular neuritis, and in seventeen patients with unilateral and thirteen patients with bilateral infratentorial lesions and compared with OKN in fifty healthy subjects. Mean and maximum slow phase velocity of OKN was calculated as well as the asymmetry of responses. The efficiency of the different variables in OKN, in discriminating b

An identification technique for the spike artefact of saccadic eye movements

Many subjects have a negative spike in the beginning of a saccade in electro-oculographic signals. The amplitude of the spike depends on the location of the electrodes. The spike distorts the saccades and causes errors in the parameters. The saccade spike can assist in the identification of small saccades. A syntactic technique based on formal languages and parsing is presented which looks for spi

Neural activity, alertness and visual orientation in intact and unilaterally labyrinthectomized rabbits

Electrical brain activity and eye movements were recorded in 10 intact and 6 unilaterally labyrinthectomized rabbits, each with implanted electrodes. The frequency of optokinetic nystagmus (OKN) and a 10-second aggregate of theta waves in the dorsal hippocampus were determined after exposure of the animals to sound, vibration and optokinetic stimulation. Each stimulus used caused significant incre

Effect of alertness on the vestibulo-ocular reflex and on the slow rise in optokinetic nystagmus in rabbits

The effect of alertness on the time constant of the vestibulo-ocular reflex (VOR) and the time constant of the slow rise of the optokinetic nystagmus (OKN) was studied in nine pigmented rabbits. When the rabbits were alerted by vibration, the time constant of the VOR was prolonged, and that of the slow rise in OKN was shortened, whereas the gain of VOR and OKN remained largely unaffected. These fi

Velocity and asymmetry of optokinetic nystagmus in the evaluation of vestibular lesions

Optokinetic nystagmus (OKN) at a constant stimulus velocity of 90 degrees/s was studied in 50 healthy subjects and three different groups of patients: 10 with vestibular neuritis (VN), 17 with unilateral infratentorial lesion (UI) and 13 patients with bilateral infratentorial lesion (BI). Among healthy subjects, OKN decreased with age in those over 42 and 44 years for maximum and mean velocity, re

The relationship of optokinetic nystagmus to pursuit eye movements, vestibular nystagmus and to saccades in humans. A clinical study

The relationship of mean velocity of optokinetic nystagmus (OKN) to pursuit eye movements (PEM), to vestibular nystagmus and to voluntary saccades was analysed in 10 patients with peripheral vestibular lesions and in 30 patients with central vestibular lesions. PEM and vestibular nystagmus were significantly correlated to OKN, suggesting that a common neural pathway is used in the generation of th

Effect of alertness and visual attention on optokinetic nystagmus in humans

The effect of alertness and visual attention on optokinetic nystagmus (OKN) and optokinetic after-nystagmus (OKAN) was studied in 20 volunteers. Electroencephalographic (EEG) activity was recorded over the occipital lobe. Exposure to sound and vibration caused a significant increase in the mean slow-phase velocity of OKN, whereas its maximum slow-phase velocity remained unaffected. Vibration tende

Detection of saccadic eye movements using a non-recursive adaptive digital filter

Saccadic eye movements provide important information about the neuron system at several levels. In recent years computer analysis of saccades has been adapted for use in clinical work. The most common detection methods do not always function without the user's control and aid. In the present paper a digital filter is described for the detection of saccades. This non-recursive filter unscrambles sa

The effects of TTS-scopolamine, dimenhydrinate, lidocaine, and tocainide on motion sickness, vertigo, and nystagmus

The effects of TTS-scopolamine, dimenhydrinate, lidocaine, and tocainide on motion sickness and vertigo and on caloric and postrotatory nystagmus were evaluated in healthy volunteers. TTS-scopolamine was administered transdermally (delivering approximately 10 micrograms X h-1 scopolamine base) and 100 mg dimenhydrinate orally. Lidocaine and tocainide were administered intravenously (average plasma

Intra-individual variation in oculomotor performance in man

Peak velocity of saccade, maximum velocity of smooth pursuit, and peak velocity of slow phase of vestibular and optovestibular nystagmus were measured three times daily on three separate days in 6 healthy subjects in order to estimate the intra-individual variation of the results of oculomotor tests. Analysis of variance revealed that the oculomotor performance of the individual subjects varied sy

A reduction of vestibulo-visual integration during transdermally administered scopolamine and dimenhydrinate. A presentation of gain control theory in motion sickness

The effect of transdermally administered scopolamine (TTS scopolamine) (release rate 5 micrograms/h) and dimenhydrinate (100 mg) was examined on optovestibular nystagmus in 16 volunteers in a randomized double-blind trial. A statistically significant decrease in the optokinetic part of nystagmus was observed during all treatments. Most profound reduction was found during treatment with two TTS sco

Visually evoked slow eye movements, visual-vestibular interaction, and infratentorial lesions

The maximum velocity gain of smooth pursuit and optokinetic, vestibular, and optovestibular slow phases was examined in 15 patients with pontine, 10 with medullary, 10 with cerebellar, and 5 with combined cerebello-brain stem disorders. Marked dissociations were observed between smooth pursuit and optokinetic slow phases, especially in medullary disease. A cerebellar deficit enhanced slow phase ve

Utopology : A Re-Interrogation of the Utopian in Architecture

Utopia – the word is simultaneously evocative of hope and dread. As a concept it is stupendously problematic, and yet despite its alleged passing into irrelevance, utopia still remains a household word. Why is this so?Utopia has been reduced to a category. We place a solution in the category of the utopian or, conversely, the not-utopian. Without fail, discussions involving utopia will eventually

A short history of chromosome rearrangements and gene fusions in cancer

The molecular characterization of recurrent chromosome aberrations in the early 1980s laid the foundation for gene fusion detection in cancer. This approach remained the unrivalled method to identify fusion genes for a quarter of a century and led to the detection of more than 700 neoplasia-associated fusion genes. The advancement of deep sequencing in the mid-2000s revolutionized the search for c