• Journal of the Korean Academy of Clinical Electrophysiology
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• v.2 no.3
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• pp.65-73
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• 2004

In experimental method, this study was that galvanic vestibular stimulation in vestibular system influenced the excitability of spinal neuron through. H-reflex was measured by galvanic vestibular stimulation of binaural(right-negative pole and left-positive pole) at left head turning and prone position in sixteen normal subjects in their twenties age were selected. The summary of the comparison results were obtained below. 1. In the change of H reflex according to galvanic vestibular stimulation(GVS), Hmax amplitude(p<.05) increased significantly after stimulation. 2. In the change of H reflex according to galvanic vestibular stimulation(GVS), Hmax/Mmax ratio(p<.05) increased significantly after stimulation. In the conclusion, galvanic vestibular stimulation influenced the excitability of vestibulospinal tract and spinal neuron.

• Annals of Clinical Neurophysiology
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• v.7 no.1
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• pp.1-6
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• 2005

Loud click or tone burst sound can activate vestibular receptor and evoke reflex changes in tonic electromyographic activity within the stenocleidomastoid muscles. This reflex is assumed to originate in the saccule, the afferent pathways being the inferior vestibular nerve, and the efferent pathways the vestibulospinal tract. Averaging these muscular responses allows vestibular evoked myogenic potentials (VEMP) to be obtained. The earliest response ipsilateral to a loud click, p13n23, is dependent upon vestibular activation, specifically saccular afferents. These new techniques are beginning to be applied clinically in the patient of vestibular neuritis, Meniere's disease, acoustic neuromas, Tullio phenomenon, etc. VEMP recording will provide both a straightforward non-invasive exploration of each vestibule independently and an attractive method by which to explore otolithic receptors and vestibulospinal pathways.

• Annals of Clinical Neurophysiology
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• v.22 no.2
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• pp.67-74
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• 2020

Vestibular-evoked myogenic potentials (VEMPs) are useful for evaluating the vestibulocollic reflex arising mostly from the saccule and the vestibuloocular reflex originating from the utricle. VEMPs can vary with the characteristics of the applied stimuli and the effects of aging and diseases. VEMPs have been found to be useful for diagnosing superior canal dehiscence, but their usefulness for other clinical disorders remains unclear. This review discusses the principles of VEMP tests and summarizes the findings for VEMPs in common vestibular disorders.

• The Korean Journal of Physiology and Pharmacology
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• v.1 no.3
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• pp.275-284
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• 1997

Unilateral labyrinthectorny (ULX) causes autonomic symptoms, ocular and postural asymmetries, which disappear over tune in the process of equilibrium recovery known as vestibular compensation. In the present study in order to elucidate mechanisms responsible for the effects of electrical stimulation on vestibular compensation and investigate the relationship between vestibular compensation and c-Fos expression in the medial vestibular nuclei following ULX, we measured spontaneous nystagmus, eye movement induced by sinusoidal rotation and c-Fos expression or to 72 hs after ULX in Sprague-Dawley rats. Experimental animals were divided into two groups: ULX group with ULX only, and electrical stimulation (ES) group with electrical stimulation of $-2{\sim}-5V$, 1.0ms, 100 Hz to the lesioned vestibular system for 4 hs/day. Spontaneous nystagmus following ULX disappeared by 72 hs in ULX group and 36 hs in ES group. In eye movement induced by sinusoidal rotation, normal pattern of eye movement by rotation toward the lesioned side was recovered 24 hs after ULX at rotation of 0.1 Hz and 6 hs after at 0.2 Hz, 0.5 Hz in ULX group. In ES group, the eye movement recovered after 12 hs at 0.1 Hz, 6 hs at 0.2 Hz, and 4 hs at 0.5 Hz. Directional Preponderance which represents the symmetry of bilateral vestibular functions showed significantly early recovery in ES group compared with that of ULX group. Expression or c-Fos immunoreactive cells in the bilateral medial vestibular nuclei was severely asymmetrical till 36 hs in ULX group, and then it became a symmetry and disappeared after 72 hs. However, ES group showed the symmetry of c-Fos expression after 6 hs, which was significantly early recovery in 25 group. All these findings suggest that electrical stimulation ameliorates recovery of vestibuloocular reflex following ULX by the restoration of the balance of the resting activity between bilateral medial vestibular nuclei. In addition, c-Fos expression in the medial vestibular nuclei could be used as a marker of vestibular compensation since c-Fos expression is closely related to the course of recovery following ULX.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.4
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• pp.423-428
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• 2017

Vestibular compensation is a recovery process from vestibular symptoms over time after unilateral loss of peripheral vestibular end organs. The aim of the present study was to observe time-dependent changes in long-term potentiation (LTP) at Schaffer collateral-CA1 synapses in the CA1 area of the hippocampus during vestibular compensation. The input-output (I/O) relationships of fEPSP amplitudes and LTP induced by theta burst stimulation to Schaffer's collateral commissural fibers were evaluated from the CA1 area of hippocampal slices at 1 day, 1 week, and 1 month after unilateral labyrinthectomy (UL). The I/O relationships of fEPSPs in the CA1 area was significantly reduced within 1 week post-op and then showed a non-significant reduction at 1 month after UL. Compared with sham-operated animals, there was a significant reduction of LTP induction in the hippocampus at 1 day and 1 week after UL. However, LTP induction levels in the CA1 area of the hippocampus also returned to those of sham-operated animals 1 month following UL. These data suggest that unilateral injury of the peripheral vestibular end organs results in a transient deficit in synaptic plasticity in the CA1 hippocampal area at acute stages of vestibular compensation.

• The Journal of Korean Physical Therapy
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• v.23 no.6
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• pp.71-76
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• 2011

Purpose: We investigated a better method to enhance the vestibular system including balancing by comparing the vestibular stimulation exercise (VSE) and galvanic vestibular stimulation (GVS). Methods: The study was performed with 40 subjects randomized into four groups, including a control group, a VSE group, a GVS group, and a VSE with GVS group. The subjects of VSE performed a forward and backward roll, a right side and left side roll, and an equilibrium board in vestibular stimulation training. GVS was applied for 10 minutes and the cathode and anode side were then changed and GVS was then applied for the remaining 10 minutes. GVS was applied for 20 minutes to the subjects of this group after completion of the VSE program. Results: In the control group, all conditions were significantly decreased (p<0.05) compared to the VSE with GVS group. Also, the center of pressure (CoP) surface was more significantly decreased (p<0.01) and the CoP speed was significantly decreased in the one legged stance (p<0.05) in the control group compared to the GVS group. Conclusion: These findings suggested that GVS training increases balance ability in a narrow width. VSE with GVS training is therefore recommend as the superior method. Using GVS or VSE with GVS training is considered to clinically improve balance ability by stimulating the vestibular system.

• The Korean Journal of Food & Health Convergence
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• v.5 no.6
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• pp.1-4
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• 2019

Wernicke korsakoff syndrome is caused by thiamine deficiency in the body. Thiamine not available in the body, is a substance to be taken from outside with foods. There are some conditions that reduce the metabolism of thiamine taken from the body and cause a vital risk. The most important factor is alcoholism. Wernicke Korsakoff syndrome produces both neurological and vestibular symptoms. At the same time, the damage of these symptoms to the patient psychology cannot be ignored. The aim of this study is to investigate the damage and mechanism of the syndrome in the vestibular system. In this study, we investigated vestibular symptoms of Wernicke Korsakoff syndrome due to thiamine deficiency, differences of vestibular system according to individuals and mechanism of damage caused by syndrome in vestibular system. Thiamine deficiency is caused by Wernicke Karsokoff syndrome with some external factors. This syndrome shows the most important effects of alcoholism. It causes neurological, vestibular and psychological symptoms. In this context, we can say that thiamine deficiency is a disease that causes damage in the vestibular system due to nystagmus formation and imbalance. The most important detail in the treatment stage is the detailed evaluation of symptoms associated with each other.

• The Korean Journal of Physiology and Pharmacology
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• v.10 no.3
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• pp.131-135
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• 2006

Coeruleo-vestibular pathway which connects locus coeruleus and vestibular nuclei is noradrenergic. This study was designed to elucidate the effects of phenylephrine on the spontaneous activity of acutely isolated medial vestibular nuclear neurons of rat by whole-cell patch-clamp technique. Sprague-Dawley rats, aged 14 to 16 days, were used. After enzymatic digestion, dissociated medial vestibular neurons were transferred to a recording chamber mounted on an inverted microscope, and spontaneous action potentials were recorded by standard patch-clamp techniques. In current-clamp mode, the frequency of spontaneous action potential of medial vestibular nuclear neurons was decreased by phenylephrine (n=15). Phenylephrine increased the amplitude of afterhyperpolarization without changes in the resting membrane potential and spike width. In voltage-clamp mode, the whole potassium currents of the medial vestibular nuclear neurons were increased by phenylephrine (n=12). These experimental results suggest that ${\alpha}-receptor$ mediates the inhibitory effects on the neuronal activity of the medial vestibular nuclear neuron.

• Korean Journal of Acupuncture
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• v.25 no.3
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• pp.117-135
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• 2008

Objectives: It is known that the vestibular imbalance leads to vestibular symptoms such as nausea, vomiting, vertigo and postural disturbance. Since the non-labyrinthine inputs from the limbs and viscera converge on the vestibular nucleus neurons receiving signal from peripheral vestibular endorgan, acupuncture to the periphery may influence the activities of vestibular nuclear neurons and produce a therapeutic effect on the vestibulacr symptoms. The present study was to examine a modification and characteristics of the static and dynamic activities of medial vestibular nucleus (MVN) neurons following electroacupuncture (EA) of GB43' acupoint. Methods: In 54 Sprague-Dawley adult male rats weighing 250${\sim}$300g, spontaneous firing discharges and dynamic responses induced by sinusoidal whole body rotation about vertical axis at 0.2 Hz were observed in MVN of rats during EA of GB43' acupoint, located between the left 4th and 5th toe, which is the territory of sural and peroneal nerves, with 0.2 ms, 40 Hz and 600${\pm}$200 ${\mu}A$. Results: EA of the left GB43' acupoint induced modifications of spontaneous firing rates in 45% of MVN neurons recorded, and the percentage of modified neurons was 44% in type I, 52% in type II and 46% in non-type neurons. The excitatory or inhibitory responses of spontaneous firing discharges were predominant in the ipsilateral MVN neurons during EA. The excitatory response was abolished after EA but the inhibitory response was prolonged after EA in the ipsilateral MVN. The neurons of MVN showing modified spontaneous firing discharges by EA showed lower frequency (${\geq}$10 spikes/sec) of mean spontaneous firing rates than non affected ones. Conclusion: These results suggest that the neuronal activities of MVN neurons were influenced by EA of GB43' acupoint and the effects of EA may be related to the convergence of the peripheral vestibular inputs and ascending somatosensory inputs on MVN.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.8 no.2
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• pp.19-24
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• 2010

Purpose : This study aims to examine the influences of galvanic vestibular stimulation on autonomic reaction of normal adults. Methods : Participants in this research totaled 28 (14 men and 14 women). Galvanic vestibular stimulation was conducted with a binaural electrode configuration for 60 sec. Galvanic vestibular stimulation measurements were conducted with the subjects in a prone position. Measured items included skin conductance, blood flow, pulse rate, and respiratory rate. Measurements were repeated for a total of five times, before application, during application, after application, 5 minutes after application and 10 minutes after application. Results : Skin conductance reaction showed statistically significant differences in changes depending on time after galvanic vestibular stimulation and there were statistically differences in changes of blood flow, pulse rate and respiratory rate after galvanic vestibular stimulation. Conclusion : Blood flow, pulse rate and respiratory rate of autonomic reactions were not influenced by galvanic vestibular stimulation, but skin conductance reaction was influenced by it and it was found that it was reduced during and after stimulation rather than before stimulation. Consequently, it was considered that galvanic vestibular stimulation affected the autonomic reaction.