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Sample records for vestibular neuronitis

  1. Vestibular Neuronitis

    ... Prevent Painful Swimmer's Ear Additional Content Medical News Vestibular Neuronitis By Lawrence R. Lustig, MD NOTE: This ... Drugs Herpes Zoster Oticus Meniere Disease Purulent Labyrinthitis Vestibular Neuronitis Vestibular neuronitis is a disorder characterized by ...

  2. Vestibular efferent neurons project to the flocculus

    Shinder, M. E.; Purcell, I. M.; Kaufman, G. D.; Perachio, A. A.

    2001-01-01

    A bilateral projection from the vestibular efferent neurons, located dorsal to the genu of the facial nerve, to the cerebellar flocculus and ventral paraflocculus was demonstrated. Efferent neurons were double-labeled by the unilateral injections of separate retrograde tracers into the labyrinth and into the floccular and ventral parafloccular lobules. Efferent neurons were found with double retrograde tracer labeling both ipsilateral and contralateral to the sites of injection. No double labeling was found when using a fluorescent tracer with non-fluorescent tracers such as horseradish peroxidase (HRP) or biotinylated dextran amine (BDA), but large percentages of efferent neurons were found to be double labeled when using two fluorescent substances including: fluorogold, microruby dextran amine, or rhodamine labeled latex beads. These data suggest a potential role for vestibular efferent neurons in modulating the dynamics of the vestibulo-ocular reflex (VOR) during normal and adaptive conditions.

  3. Vestibular convergence patterns in vestibular nuclei neurons of alert primates

    Dickman, J. David; Angelaki, Dora E.

    2002-01-01

    Sensory signal convergence is a fundamental and important aspect of brain function. Such convergence may often involve complex multidimensional interactions as those proposed for the processing of otolith and semicircular canal (SCC) information for the detection of translational head movements and the effective discrimination from physically congruent gravity signals. In the present study, we have examined the responses of primate rostral vestibular nuclei (VN) neurons that do not exhibit any eye movement-related activity using 0.5-Hz translational and three-dimensional (3D) rotational motion. Three distinct neural populations were identified. Approximately one-fourth of the cells exclusively encoded rotational movements (canal-only neurons) and were unresponsive to translation. The canal-only central neurons encoded head rotation in SCC coordinates, exhibited little orthogonal canal convergence, and were characterized with significantly higher sensitivities to rotation as compared to primary SCC afferents. Another fourth of the neurons modulated their firing rates during translation (otolith-only cells). During rotations, these neurons only responded when the axis of rotation was earth-horizontal and the head was changing orientation relative to gravity. The remaining one-half of VN neurons were sensitive to both rotations and translations (otolith + canal neurons). Unlike primary otolith afferents, however, central neurons often exhibited significant spatiotemporal (noncosine) tuning properties and a wide variety of response dynamics to translation. To characterize the pattern of SCC inputs to otolith + canal neurons, their rotational maximum sensitivity vectors were computed using exclusively responses during earth-vertical axis rotations (EVA). Maximum sensitivity vectors were distributed throughout the 3D space, suggesting strong convergence from multiple SCCs. These neurons were also tested with earth-horizontal axis rotations (EHA), which would activate

  4. Otolith-Canal Convergence In Vestibular Nuclei Neurons

    Dickman, J. David; Si, Xiao-Hong

    2002-01-01

    The current final report covers the period from June 1, 1999 to May 31, 2002. The primary objective of the investigation was to determine how information regarding head movements and head position relative to gravity is received and processed by central vestibular nuclei neurons in the brainstem. Specialized receptors in the vestibular labyrinths of the inner ear function to detect angular and linear accelerations of the head, with receptors located in the semicircular canals transducing rotational head movements and receptors located in the otolith organs transducing changes in head position relative to gravity or linear accelerations of the head. The information from these different receptors is then transmitted to central vestibular nuclei neurons which process the input signals, then project the appropriate output information to the eye, head, and body musculature motor neurons to control compensatory reflexes. Although a number of studies have reported on the responsiveness of vestibular nuclei neurons, it has not yet been possible to determine precisely how these cells combine the information from the different angular and linear acceleration receptors into a correct neural output signal. In the present project, rotational and linear motion stimuli were separately delivered while recording responses from vestibular nuclei neurons that were characterized according to direct input from the labyrinth and eye movement sensitivity. Responses from neurons receiving convergent input from the semicircular canals and otolith organs were quantified and compared to non-convergent neurons.

  5. Neurons excitability changes in rat medial vestibular nucleus following vestibular neurectomy

    金麟毅

    2008-01-01

    Intrinsic excitabilities of acutely isolated medial vestibular nucleus (MVN) neurons of rats with normal labyrinth and with undergoingvestibular compensation from 30 min to 24 h after unilateral vestibular deafferentation (UVD) were compared. In control rats, proportions of type A andB cells were 30 and 70%, respectively, however, the proportion of type A cells increased following UVD. Bursting discharge and irregular firingpatterns were recorded from 2 to 12 h post UVD. The spontaneous discharge rate of neurons in the ipsilesional MVN increased significantly at 2 hpost-UVD and remained high until 12 h post-UVD in both type A and type B cells. Mter-hyperpolarization (AHP) of the MVN neurons decreasedsignificantly from 2 h post-UVD in both types of cells. These results suggest that the early stage of vestibular compensation after peripheralneurectomy is associated with an increase in intrinsic excitability due to reduction of AHP in MVN neurons.

  6. Control of hair cell excitability by vestibular primary sensory neurons.

    Brugeaud, Aurore; Travo, Cécile; Demêmes, Danielle; Lenoir, Marc; Llorens, Jordi; Puel, Jean-Luc; Chabbert, Christian

    2007-01-01

    In the rat utricle, synaptic contacts between hair cells and the nerve fibers arising from the vestibular primary neurons form during the first week after birth. During that period, the sodium-based excitability that characterizes neonate utricle sensory cells is switched off. To investigate whether the establishment of synaptic contacts was responsible for the modulation of the hair cell excitability, we used an organotypic culture of rat utricle in which the setting of synapses was prevente...

  7. Convergence of limb, visceral, and vertical semicircular canal or otolith inputs onto vestibular nucleus neurons

    Jian, B. J.; Shintani, T.; Emanuel, B. A.; Yates, B. J.

    2002-01-01

    The major goal of this study was to determine the patterns of convergence of non-labyrinthine inputs from the limbs and viscera onto vestibular nucleus neurons receiving signals from vertical semicircular canals or otolith organs. A secondary aim was to ascertain whether the effects of non-labyrinthine inputs on the activity of vestibular nucleus neurons is affected by bilateral peripheral vestibular lesions. The majority (72%) of vestibular nucleus neurons in labyrinth-intact animals whose firing was modulated by vertical rotations responded to electrical stimulation of limb and/or visceral nerves. The activity of even more vestibular nucleus neurons (93%) was affected by limb or visceral nerve stimulation in chronically labyrinthectomized preparations. Some neurons received non-labyrinthine inputs from a variety of peripheral sources, including antagonist muscles acting at the same joint, whereas others received inputs from more limited sources. There was no apparent relationship between the spatial and dynamic properties of a neuron's responses to tilts in vertical planes and the non-labyrinthine inputs that it received. These data suggest that non-labyrinthine inputs elicited during movement will modulate the processing of information by the central vestibular system, and may contribute to the recovery of spontaneous activity of vestibular nucleus neurons following peripheral vestibular lesions. Furthermore, some vestibular nucleus neurons with non-labyrinthine inputs may be activated only during particular behaviors that elicit a specific combination of limb and visceral inputs.

  8. Infrared laser stimulation of retinal and vestibular neurons

    Bardin, Fabrice; Bec, Jean-Michel; Albert, Emmanuelle S.; Hamel, Christian; Dupeyron, Gérard; Chabbert, Christian; Marc, Isabelle; Dumas, Michel

    2011-03-01

    The study of laser-neuron interaction has gained interest over the last few years not only for understanding of fundamental mechanisms but also for medical applications such as prosthesis because of the non-invasive characteristic of the laser stimulation. Several authors have shown that near infrared lasers are able to stimulate neurons. It is suggested that a thermal gradient induced by the absorption of the laser radiation on cells is the primary effect but the exact mechanism remains unclear. We show in this work that infrared laser radiations provide a possible way for stimulating retinal and vestibular ganglion cells. We describe relevant physical characteristics allowing safe and reproducible neuron stimulations by single infrared pulses. Calcium fluorescence imaging and electrophysiological recordings have been used to measure ionic exchanges at the neuron membrane. The stimulation system is based on a pulsed laser diode beam of a few mW. Effects of three different wavelengths (from 1470 to 1875 nm) and stimulation durations have been investigated. Variations of the stimulation energy thresholds suggest that the main physical parameter is the water optical absorption. Measurements of the temperature at the cell membrane show that a constant temperature rise is required to stimulate neurons, suggesting a photothermal process.

  9. Synaptic plasticity in medial vestibular nucleus neurons: comparison with computational requirements of VOR adaptation.

    John R W Menzies

    Full Text Available BACKGROUND: Vestibulo-ocular reflex (VOR gain adaptation, a longstanding experimental model of cerebellar learning, utilizes sites of plasticity in both cerebellar cortex and brainstem. However, the mechanisms by which the activity of cortical Purkinje cells may guide synaptic plasticity in brainstem vestibular neurons are unclear. Theoretical analyses indicate that vestibular plasticity should depend upon the correlation between Purkinje cell and vestibular afferent inputs, so that, in gain-down learning for example, increased cortical activity should induce long-term depression (LTD at vestibular synapses. METHODOLOGY/PRINCIPAL FINDINGS: Here we expressed this correlational learning rule in its simplest form, as an anti-Hebbian, heterosynaptic spike-timing dependent plasticity interaction between excitatory (vestibular and inhibitory (floccular inputs converging on medial vestibular nucleus (MVN neurons (input-spike-timing dependent plasticity, iSTDP. To test this rule, we stimulated vestibular afferents to evoke EPSCs in rat MVN neurons in vitro. Control EPSC recordings were followed by an induction protocol where membrane hyperpolarizing pulses, mimicking IPSPs evoked by flocculus inputs, were paired with single vestibular nerve stimuli. A robust LTD developed at vestibular synapses when the afferent EPSPs coincided with membrane hyperpolarization, while EPSPs occurring before or after the simulated IPSPs induced no lasting change. Furthermore, the iSTDP rule also successfully predicted the effects of a complex protocol using EPSP trains designed to mimic classical conditioning. CONCLUSIONS: These results, in strong support of theoretical predictions, suggest that the cerebellum alters the strength of vestibular synapses on MVN neurons through hetero-synaptic, anti-Hebbian iSTDP. Since the iSTDP rule does not depend on post-synaptic firing, it suggests a possible mechanism for VOR adaptation without compromising gaze-holding and VOR

  10. Monoclonal L-citrulline immunostaining reveals nitric oxide-producing vestibular neurons

    Holstein, G. R.; Friedrich, V. L. Jr; Martinelli, G. P.

    2001-01-01

    Nitric oxide is an unstable free radical that serves as a novel messenger molecule in the central nervous system (CNS). In order to understand the interplay between classic and novel chemical communication systems in vestibular pathways, the staining obtained using a monoclonal antibody directed against L-citrulline was compared with the labeling observed using more traditional markers for the presence of nitric oxide. Brainstem tissue from adult rats was processed for immunocytochemistry employing a monoclonal antibody directed against L-citrulline, a polyclonal antiserum against neuronal nitric oxide synthase, and/or NADPH-diaphorase histochemistry. Our findings demonstrate that L-citrulline can be fixed in situ by vascular perfusion, and can be visualized in fixed CNS tissue sections by immunocytochemistry. Further, the same vestibular regions and cell types are labeled by NADPH-diaphorase histochemistry, by the neuronal nitric oxide synthase antiserum, and by our anti-L-citrulline antibody. Clusters of L-citrulline-immunoreactive neurons are present in subregions of the vestibular nuclei, including the caudal portion of the inferior vestibular nucleus, the magnocellular portion of the medial vestibular nucleus, and the large cells in the ventral tier of the lateral vestibular nucleus. NADPH-diaphorase histochemical staining of these neurons clearly demonstrated their multipolar, fusiform and globular somata and long varicose dendritic processes. These results provide support for the suggestion that nitric oxide serves key roles in both vestibulo-autonomic and vestibulo-spinal pathways.

  11. Restricted loss of olivocochlear but not vestibular efferent neurons in the senescent gerbil (Meriones unguiculatus

    Susanne eRadtke-Schuller

    2015-02-01

    Full Text Available Degeneration of hearing and vertigo are symptoms of age-related auditory and vestibular disorders reflecting multifactorial changes in the peripheral and central nervous system whose interplay remains largely unknown. Originating bilaterally in the brain stem, vestibular and auditory efferent cholinergic projections exert feedback control on the peripheral sensory organs, and modulate sensory processing. We studied age-related changes in the auditory and vestibular efferent systems by evaluating number of cholinergic efferent neurons in young adult and aged gerbils, and in cholinergic trigeminal neurons serving as a control for efferents not related to the inner ear. We observed a significant loss of olivocochlear neurons in aged compared to young adult animals, whereas the overall number of lateral superior olive cells was not reduced in aging. Although the loss of lateral and medial olivocochlear neurons was uniform and equal on both sides of the brain, there were frequency-related differences within the lateral olivocochlear neurons, where the decline was larger in the medial limb of the superior olivary nucleus (high frequency representation than in the lateral limb (middle-to-low frequency representation. In contrast, neither the number of vestibular efferent neurons, nor the population of motor trigeminal neurons were significantly reduced in the aged animals. These observations suggest differential effects of aging on the respective cholinergic efferent brainstem systems.

  12. Plasticity of Scarpa’s ganglion neurons as a possible basis for functional restoration within vestibular endorgans

    SophieGaboyard-Niay

    2012-01-01

    In a previous study (Brugeaud et al., 2007), we observed spontaneous restoration of the vestibular function in young adult rodents following excitotoxic injury of the neuronal network of vestibular endorgans. The functional restoration was supported by a repair of synaptic contacts between hair cells and primary vestibular neurons. This process was observed in 2/3 of the animals studied and occurred within five days following the synapse insult. To assess whether structural plasticity is a fu...

  13. Plasticity of Scarpa’s Ganglion Neurons as a Possible Basis for Functional Restoration within Vestibular Endorgans

    Travo, Cécile; Gaboyard-Niay, Sophie; Chabbert, Christian

    2012-01-01

    In a previous study, we observed spontaneous restoration of vestibular function in young adult rodents following excitotoxic injury of the neuronal connections within vestibular endorgans. The functional restoration was supported by a repair of synaptic contacts between hair cells and primary vestibular neurons. This process was observed in 2/3 of the animals studied and occurred within 5 days following the synaptic damage. To assess whether repair capacity is a fundamental trait of vestibula...

  14. Integrative responses of neurons in nucleus tractus solitarius to visceral afferent stimulation and vestibular stimulation in vertical planes

    Sugiyama, Yoichiro; Suzuki, Takeshi; DeStefino, Vincent J.; Yates, Bill J.

    2011-01-01

    Anatomical studies have demonstrated that the vestibular nuclei project to nucleus tractus solitarius (NTS), but little is known about the effects of vestibular inputs on NTS neuronal activity. Furthermore, lesions of NTS abolish vomiting elicited by a variety of different triggering mechanisms, including vestibular stimulation, suggesting that emetic inputs may converge on the same NTS neurons. As such, an emetic stimulus that activates gastrointestinal (GI) receptors could alter the respons...

  15. Plasticity of Scarpa’s ganglion neurons as a possible basis for functional restoration within vestibular endorgans

    SophieGaboyard-Niay

    2012-06-01

    Full Text Available In a previous study (Brugeaud et al., 2007, we observed spontaneous restoration of the vestibular function in young adult rodents following excitotoxic injury of the neuronal network of vestibular endorgans. The functional restoration was supported by a repair of synaptic contacts between hair cells and primary vestibular neurons. This process was observed in 2/3 of the animals studied and occurred within five days following the synapse insult. To assess whether structural plasticity is a fundamental trait of altered vestibular endorgans and to decipher the cellular mechanisms that support such a repair process, we studied the neuronal regeneration and synaptogenesis in co-cultures of vestibular epithelia and Scarpa’s ganglion from young and adult rodents. We demonstrate that under specific culture conditions, primary vestibular neurons from young mice or rats exhibit robust ability to regenerate nervous processes. When co-cultured with vestibular epithelia, primary vestibular neurons were able to establish de novo contacts with hair cells. Under the present paradigm, these contacts displayed morphological features of immature synaptic contacts. This reparative capacity remained in older mice although to a lesser extent. Identifying the basic mechanisms underlying the repair process may provide a basis for novel therapeutic strategies to restore mature and functional vestibular synaptic contacts following damage or loss.

  16. Convergent properties of vestibular-related brain stem neurons in the gerbil

    Kaufman, G. D.; Shinder, M. E.; Perachio, A. A.

    2000-01-01

    Three classes of vestibular-related neurons were found in and near the prepositus and medial vestibular nuclei of alert or decerebrate gerbils, those responding to: horizontal translational motion, horizontal head rotation, or both. Their distribution ratios were 1:2:2, respectively. Many cells responsive to translational motion exhibited spatiotemporal characteristics with both response gain and phase varying as a function of the stimulus vector angle. Rotationally sensitive neurons were distributed as Type I, II, or III responses (sensitive to ipsilateral, contralateral, or both directions, respectively) in the ratios of 4:6:1. Four tested factors shaped the response dynamics of the sampled neurons: canal-otolith convergence, oculomotor-related activity, rotational Type (I or II), and the phase of the maximum response. Type I nonconvergent cells displayed increasing gains with increasing rotational stimulus frequency (0.1-2.0 Hz, 60 degrees /s), whereas Type II neurons with convergent inputs had response gains that markedly decreased with increasing translational stimulus frequency (0.25-2.0 Hz, +/-0.1 g). Type I convergent and Type II nonconvergent neurons exhibited essentially flat gains across the stimulus frequency range. Oculomotor-related activity was noted in 30% of the cells across all functional types, appearing as burst/pause discharge patterns related to the fast phase of nystagmus during head rotation. Oculomotor-related activity was correlated with enhanced dynamic range compared with the same category that had no oculomotor-related response. Finally, responses that were in-phase with head velocity during rotation exhibited greater gains with stimulus frequency increments than neurons with out-of-phase responses. In contrast, for translational motion, neurons out of phase with head acceleration exhibited low-pass characteristics, whereas in-phase neurons did not. Data from decerebrate preparations revealed that although similar response types could

  17. A model for the characterization of the spatial properties in vestibular neurons

    Angelaki, D. E.; Bush, G. A.; Perachio, A. A.

    1992-01-01

    Quantitative study of the static and dynamic response properties of some otolith-sensitive neurons has been difficult in the past partly because their responses to different linear acceleration vectors exhibited no "null" plane and a dependence of phase on stimulus orientation. The theoretical formulation of the response ellipse provides a quantitative way to estimate the spatio-temporal properties of such neurons. Its semi-major axis gives the direction of the polarization vector (i.e., direction of maximal sensitivity) and it estimates the neuronal response for stimulation along that direction. In addition, the semi-minor axis of the ellipse provides an estimate of the neuron's maximal sensitivity in the "null" plane. In this paper, extracellular recordings from otolith-sensitive vestibular nuclei neurons in decerebrate rats were used to demonstrate the practical application of the method. The experimentally observed gain and phase dependence on the orientation angle of the acceleration vector in a head-horizontal plane was described and satisfactorily fit by the response ellipse model. In addition, the model satisfactorily fits neuronal responses in three-dimensions and unequivocally demonstrates that the response ellipse formulation is the general approach to describe quantitatively the spatial properties of vestibular neurons.

  18. Muscarinic receptor subtypes differentially control synaptic input and excitability of cerebellum-projecting medial vestibular nucleus neurons.

    Zhu, Yun; Chen, Shao-Rui; Pan, Hui-Lin

    2016-04-01

    Neurons in the vestibular nuclei have a vital function in balance maintenance, gaze stabilization, and posture. Although muscarinic acetylcholine receptors (mAChRs) are expressed and involved in regulating vestibular function, it remains unclear how individual mAChR subtypes regulate vestibular neuronal activity. In this study, we determined which specific subtypes of mAChRs control synaptic input and excitability of medial vestibular nucleus (MVN) neurons that project to the cerebellum. Cerebellum-projecting MVN neurons were labeled by a fluorescent retrograde tracer and then identified in rat brainstem slices. Quantitative PCR analysis suggested that M2 and M3 were the possible major mAChR subtypes expressed in the MVN. The mAChR agonist oxotremorine-M significantly reduced the amplitude of glutamatergic excitatory post-synaptic currents evoked by stimulation of vestibular primary afferents, and this effect was abolished by the M2-preferring antagonist AF-DX 116. However, oxotremorine-M had no effect on GABA-mediated spontaneous inhibitory post-synaptic currents of labeled MVN neurons. Furthermore, oxotremorine-M significantly increased the firing activity of labeled MVN neurons, and this effect was blocked by the M3-preferring antagonist J104129 in most neurons tested. In addition, AF-DX 116 reduced the onset latency and prolonged the excitatory effect of oxotremorine-M on the firing activity of labeled MVN neurons. Our findings suggest that M3 is the predominant post-synaptic mAChR involved in muscarinic excitation of cerebellum-projecting MVN neurons. Pre-synaptic M2 mAChR regulates excitatory glutamatergic input from vestibular primary afferents, which in turn influences the excitability of cerebellum-projecting MVN neurons. This new information has important therapeutic implications for treating vestibular disorders with mAChR subtype-selective agents. Medial vestibular nucleus (MVN) neurons projecting to the cerebellum are involved in balance control. We

  19. Effects of galvanic vestibular stimulation on postural limb reflexes and neurons of spinal postural network

    Hsu, L.-J.; Zelenin, P. V.; Orlovsky, G.N.; Deliagina, T. G.

    2012-01-01

    Quadrupeds maintain the dorsal side up body orientation due to the activity of the postural control system driven by limb mechanoreceptors. Binaural galvanic vestibular stimulation (GVS) causes a lateral body sway toward the anode. Previously, we have shown that this new position is actively stabilized, suggesting that GVS changes a set point in the reflex mechanisms controlling body posture. The aim of the present study was to reveal the underlying neuronal mechanisms. Experiments were perfo...

  20. Cat vestibular neurons that exhibit different responses to active and passive yaw head rotations

    Robinson, F. R.; Tomko, D. L.

    1987-01-01

    Neurons in the vestibular nuclei were recorded in alert cats during voluntary yaw rotations of the head and during the same rotations delivered with a turntable driven from a record of previous voluntary movements. During both voluntary and passive rotations, 35 percent (6/17) of neurons tested responded at higher rates or for a larger part of the movement during voluntary movements than during the same rotations delivered with the turntable. Neck sensory input was evaluated separately in many of these cells and can account qualitatively for the extra firing present during active movement.

  1. [Vestibular compensation studies]. [Vestibular Compensation and Morphological Studies

    Perachio, Adrian A. (Principal Investigator)

    1996-01-01

    The following topics are reported: neurophysiological studies on MVN neurons during vestibular compensation; effects of spinal cord lesions on VNC neurons during compensation; a closed-loop vestibular compensation model for horizontally canal-related MVN neurons; spatiotemporal convergence in VNC neurons; contributions of irregularly firing vestibular afferents to linear and angular VOR's; application to flight studies; metabolic measures in vestibular neurons; immediate early gene expression following vestibular stimulation; morphological studies on primary afferents, central vestibular pathways, vestibular efferent projection to the vestibular end organs, and three-dimensional morphometry and imaging.

  2. Inputs from regularly and irregularly discharging vestibular nerve afferents to secondary neurons in squirrel monkey vestibular nuclei. III. Correlation with vestibulospinal and vestibuloocular output pathways

    Boyle, R.; Goldberg, J. M.; Highstein, S. M.

    1992-01-01

    1. A previous study measured the relative contributions made by regularly and irregularly discharging afferents to the monosynaptic vestibular nerve (Vi) input of individual secondary neurons located in and around the superior vestibular nucleus of barbiturate-anesthetized squirrel monkeys. Here, the analysis is extended to more caudal regions of the vestibular nuclei, which are a major source of both vestibuloocular and vestibulospinal pathways. As in the previous study, antidromic stimulation techniques are used to classify secondary neurons as oculomotor or spinal projecting. In addition, spinal-projecting neurons are distinguished by their descending pathways, their termination levels in the spinal cord, and their collateral projections to the IIIrd nucleus. 2. Monosynaptic excitatory postsynaptic potentials (EPSPs) were recorded intracellularly from secondary neurons as shocks of increasing strength were applied to Vi. Shocks were normalized in terms of the threshold (T) required to evoke field potentials in the vestibular nuclei. As shown previously, the relative contribution of irregular afferents to the total monosynaptic Vi input of each secondary neuron can be expressed as a %I index, the ratio (x100) of the relative sizes of the EPSPs evoked by shocks of 4 x T and 16 x T. 3. Antidromic stimulation was used to type secondary neurons as 1) medial vestibulospinal tract (MVST) cells projecting to spinal segments C1 or C6; 2) lateral vestibulospinal tract (LVST) cells projecting to C1, C6; or L1; 3) vestibulooculo-collic (VOC) cells projecting both to the IIIrd nucleus and by way of the MVST to C1 or C6; and 4) vestibuloocular (VOR) neurons projecting to the IIIrd nucleus but not to the spinal cord. Most of the neurons were located in the lateral vestibular nucleus (LV), including its dorsal (dLV) and ventral (vLV) divisions, and adjacent parts of the medial (MV) and descending nuclei (DV). Cells receiving quite different proportions of their direct inputs

  3. Reconsidering the role of neuronal intrinsic properties and neuromodulation in vestibular homeostasis

    Mathieu eBeraneck

    2012-02-01

    Full Text Available The sensorimotor transformations performed by central vestibular neurons (2°VN constantly adapt as the animal faces conflicting sensory information or sustains injuries. In order to ensure the homeostasis of vestibular-related functions, neural changes could in part rely on the regulation of 2°VN intrinsic properties. Here, we review evidence which demonstrates modulation and plasticity of 2°VN intrinsic properties. We first present partition of rodents 2°VN into distinct subtypes, namely type A and type B. Then, we focus on the respective properties of each type and their putative roles in vestibular functions. The intrinsic properties of 2°VN can be swiftly modulated by a wealth of neuromodulators, to adapt rapidly, for example, to temporary changes of the ecophysiological surroundings. To illustrate how intrinsic excitability can rapidly be modified in physiological conditions and therefore be targeted in the clinic, we present the modulation of vestibular reflexes in relation to the neuromodulatory fluctuation of the sleep/wake cycle. On the other hand, intrinsic properties can also be slowly yet deeply modified in response to major perturbations as is the case following a unilateral labyrinthectomy (UL. We revisit the experimental evidence which demonstrate that drastic alterations of the 2°VN intrinsic properties occur following UL, however with a slow dynamic, more on par with the compensation of dynamic deficits than static ones. Data are interpreted in the framework of a distributed process which progress from the global, large scale coping mechanisms (e.g. changes in behavioural strategies to the local, small scale ones (e.g. changes in intrinsic properties. Within this framework, the compensation of dynamic deficits improves with time as deeper modifications are engraved within the finer parts of the vestibular-related networks. Finally, we propose perspectives and working hypotheses to pave the way for future research aiming at

  4. Two-dimensional spatiotemporal coding of linear acceleration in vestibular nuclei neurons

    Angelaki, D. E.; Bush, G. A.; Perachio, A. A.

    1993-01-01

    Response properties of vertical (VC) and horizontal (HC) canal/otolith-convergent vestibular nuclei neurons were studied in decerebrate rats during stimulation with sinusoidal linear accelerations (0.2-1.4 Hz) along different directions in the head horizontal plane. A novel characteristic of the majority of tested neurons was the nonzero response often elicited during stimulation along the "null" direction (i.e., the direction perpendicular to the maximum sensitivity vector, Smax). The tuning ratio (Smin gain/Smax gain), a measure of the two-dimensional spatial sensitivity, depended on stimulus frequency. For most vestibular nuclei neurons, the tuning ratio was small at the lowest stimulus frequencies and progressively increased with frequency. Specifically, HC neurons were characterized by a flat Smax gain and an approximately 10-fold increase of Smin gain per frequency decade. Thus, these neurons encode linear acceleration when stimulated along their maximum sensitivity direction, and the rate of change of linear acceleration (jerk) when stimulated along their minimum sensitivity direction. While the Smax vectors were distributed throughout the horizontal plane, the Smin vectors were concentrated mainly ipsilaterally with respect to head acceleration and clustered around the naso-occipital head axis. The properties of VC neurons were distinctly different from those of HC cells. The majority of VC cells showed decreasing Smax gains and small, relatively flat, Smin gains as a function of frequency. The Smax vectors were distributed ipsilaterally relative to the induced (apparent) head tilt. In type I anterior or posterior VC neurons, Smax vectors were clustered around the projection of the respective ipsilateral canal plane onto the horizontal head plane. These distinct spatial and temporal properties of HC and VC neurons during linear acceleration are compatible with the spatiotemporal organization of the horizontal and the vertical/torsional ocular responses

  5. Spatiotemporal processing of linear acceleration: primary afferent and central vestibular neuron responses

    Angelaki, D. E.; Dickman, J. D.

    2000-01-01

    -pass" filter properties exhibit semicircular canal-like dynamics during head tilts might have important consequences for the conclusions of previous studies of sensory convergence and sensorimotor transformations in central vestibular neurons.

  6. Spatiotemporal processing of linear acceleration: primary afferent and central vestibular neuron responses

    Angelaki, D. E.; Dickman, J. D.

    2000-01-01

    Spatiotemporal convergence and two-dimensional (2-D) neural tuning have been proposed as a major neural mechanism in the signal processing of linear acceleration. To examine this hypothesis, we studied the firing properties of primary otolith afferents and central otolith neurons that respond exclusively to horizontal linear accelerations of the head (0.16-10 Hz) in alert rhesus monkeys. Unlike primary afferents, the majority of central otolith neurons exhibited 2-D spatial tuning to linear acceleration. As a result, central otolith dynamics vary as a function of movement direction. During movement along the maximum sensitivity direction, the dynamics of all central otolith neurons differed significantly from those observed for the primary afferent population. Specifically at low frequencies (frequency. "Flat" neurons were characterized by relatively flat gains and constant phase lags (approximately 20-55 degrees ). A few neurons ("low-pass") were characterized by decreasing gain and phase as a function of frequency. The response dynamics of central otolith neurons suggest that the approximately 90 degrees phase lags observed at low frequencies are not the result of a neural integration but rather the effect of nonminimum phase behavior, which could arise at least partly through spatiotemporal convergence. Neither afferent nor central otolith neurons discriminated between gravitational and inertial components of linear acceleration. Thus response sensitivity was indistinguishable during 0.5-Hz pitch oscillations and fore-aft movements. The fact that otolith-only central neurons with "high-pass" filter properties exhibit semicircular canal-like dynamics during head tilts might have important consequences for the conclusions of previous studies of sensory convergence and sensorimotor transformations in central vestibular neurons.

  7. Fos expression in neurons of the rat vestibulo-autonomic pathway activated by sinusoidal galvanic vestibular stimulation

    Gay R Holstein

    2012-02-01

    Full Text Available The vestibular system sends projections to brainstem autonomic nuclei that modulate heart rate and blood pressure in response to changes in head and body position with regard to gravity. Consistent with this, binaural sinusoidal galvanic vestibular stimulation (sGVS in humans causes vasoconstriction in the legs, while low frequency (0.02-0.04 Hz sGVS causes a rapid drop in heart rate and blood pressure in anesthetized rats. We have hypothesized that these responses occur through activation of vestibulo-sympathetic pathways. In the present study, c-Fos protein expression was examined in neurons of the vestibular nuclei and rostral ventrolateral medullary region (RVLM that were activated by low frequency sGVS. We found c-Fos-labeled neurons in the spinal, medial and superior vestibular nuclei (SpVN, MVN and SVN, respectively and the parasolitary nucleus. The highest density of c-Fos-positive vestibular nuclear neurons was observed in MVN, where immunolabeled cells were present throughout the rostro-caudal extent of the nucleus. C-Fos expression was concentrated in the parvocellular region and largely absent from magnocellular MVN. C-Fos-labeled cells were scattered throughout caudal SpVN, and the immunostained neurons in SVN were restricted to a discrete wedge-shaped area immediately lateral to the IVth ventricle. Immunofluorescence localization of c-Fos and glutamate revealed that approximately one third of the c-Fos-labeled vestibular neurons showed intense glutamate-like immunofluorescence, far in excess of the stain reflecting the metabolic pool of cytoplasmic glutamate. In the RVLM, which receives a direct projection from the vestibular nuclei and sends efferents to preganglionic sympathetic neurons in the spinal cord, we observed an approximately 3-fold increase in c-Fos labeling in the sGVS-activated rats. We conclude that localization of c-Fos protein following sGVS is a reliable marker for sGVS-activated neurons of the vestibulo

  8. ELECTROPHYSIOLOGICAL PROPERTIES OF MORPHOLOGICALLY-IDENTIFIED MEDIAL VESTIBULAR NUCLEUS NEURONS PROJECTING TO THE ABDUCENS NUCLEUS IN THE CHICK EMBRYO

    Gottesman-Davis, Adria; Shao, Mei; Hirsch, June C.; Peusner, Kenna D.

    2010-01-01

    Neurons in the medial vestibular nucleus (MVN) show a wide range of axonal projection pathways, intrinsic firing properties, and responses to head movements. To determine whether MVN neurons participating in the vestibulocular reflexes (VOR) have distinctive electrophysiological properties related to their output pathways, a new preparation was devised using transverse brain slices containing the chicken MVN and abducens nucleus. Biocytin Alexa Fluor was injected extracellularly into the abdu...

  9. Response of pontomedullary reticulospinal neurons to vestibular stimuli in vertical planes. Role in vertical vestibulospinal reflexes of the decerebrate cat

    Bolton, P. S.; Goto, T.; Schor, R. H.; Wilson, V. J.; Yamagata, Y.; Yates, B. J.

    1992-01-01

    1. To investigate the neural substrate of vestibulospinal reflexes in decerebrate cats, we studied the responses of pontomedullary reticulospinal neurons to natural stimulation of the labyrinth in vertical planes. Our principal aim was to determine whether reticulospinal neurons that terminate in, or are likely to give off collaterals to, the upper cervical segments had properties similar to those of the vestibulocollic reflex (VCR). 2. Antidromic stimulation was used to determine whether the neurons projected to the neck, lower cervical, thoracic, or lumbar levels. Dynamics of the responses of spontaneously firing neurons were studied with sinusoidal stimuli delivered at 0.05-1 Hz and aligned to the plane of body rotation, that produced maximal modulation of the neuron (response vector orientation). Each neuron was assigned a vestibular input classification of otolith, vertical canal, otolith + canal, or spatial-temporal convergence (STC). 3. We found, in agreement with previous studies, that the largest fraction of pontomedullary reticulospinal neurons projected to the lumbar cord, and that only a small number ended in the neck segments. Neurons projecting to all levels of the spinal cord had similar responses to labyrinth stimulation. 4. Reticulospinal neurons that received only vertical canal inputs were rare (1 of 67 units). Most reticulospinal neurons (48%) received predominant otolith inputs, 18% received otolith + canal input, and only 9% had STC behavior. These data are in sharp contrast to the results of our previous studies of vestibulospinal neurons. A considerable portion of vestibulospinal neurons receives vertical canal input (38%), fewer receive predominantly otolith input (22%), whereas the proportion that have otolith + canal input or STC behavior is similar to our present reticulospinal data. 5. The response vector orientations of our reticulospinal neurons, particularly those with canal inputs (canal, otolith + canal, STC) were predominantly in

  10. Firing behavior of vestibular neurons during active and passive head movements: vestibulo-spinal and other non-eye-movement related neurons

    McCrea, R. A.; Gdowski, G. T.; Boyle, R.; Belton, T.; Peterson, B. W. (Principal Investigator)

    1999-01-01

    The firing behavior of 51 non-eye movement related central vestibular neurons that were sensitive to passive head rotation in the plane of the horizontal semicircular canal was studied in three squirrel monkeys whose heads were free to move in the horizontal plane. Unit sensitivity to active head movements during spontaneous gaze saccades was compared with sensitivity to passive head rotation. Most units (29/35 tested) were activated at monosynaptic latencies following electrical stimulation of the ipsilateral vestibular nerve. Nine were vestibulo-spinal units that were antidromically activated following electrical stimulation of the ventromedial funiculi of the spinal cord at C1. All of the units were less sensitive to active head movements than to passive whole body rotation. In the majority of cells (37/51, 73%), including all nine identified vestibulo-spinal units, the vestibular signals related to active head movements were canceled. The remaining units (n = 14, 27%) were sensitive to active head movements, but their responses were attenuated by 20-75%. Most units were nearly as sensitive to passive head-on-trunk rotation as they were to whole body rotation; this suggests that vestibular signals related to active head movements were cancelled primarily by subtraction of a head movement efference copy signal. The sensitivity of most units to passive whole body rotation was unchanged during gaze saccades. A fundamental feature of sensory processing is the ability to distinguish between self-generated and externally induced sensory events. Our observations suggest that the distinction is made at an early stage of processing in the vestibular system.

  11. Mechanisms of Sustained High Firing Rates in Two Classes of Vestibular Nucleus Neurons: Differential Contributions of Resurgent Na, Kv3, and BK Currents

    Gittis, Aryn H.; Moghadam, Setareh H.; du Lac, Sascha

    2010-01-01

    To fire at high rates, neurons express ionic currents that work together to minimize refractory periods by ensuring that sodium channels are available for activation shortly after each action potential. Vestibular nucleus neurons operate around high baseline firing rates and encode information with bidirectional modulation of firing rates up to several hundred Hz. To determine the mechanisms that enable these neurons to sustain firing at high rates, ionic currents were measured during firing ...

  12. THE COMPARATIVE CHARACTERISTICS OF BACKGROUND IMPULSE ACTIVITY OF IPSI- AND CONTRALATERAL MEDIAL VESTIBULAR NUCLUS NEURONS IN LABYRINTHECTOMIZED RATS

    S.H.Sarkisyan

    2011-02-01

    Full Text Available The background neuronal impulse activity of right and left medial vestibular nuclei of rats was carried out in norm and after unilateral labyrinthectomy (UL on 2-d, 7-th, 12-th and 17-th days. It was shown by computer analysis, that characteristics of both nuclei neurons impulse activity in the control group have revealled primery asymmetry of the average freguency of variation (accordingly 16,6±1,7 Hz; and 23,6±1,5 Hz; p<0,01. It is shown that on 7-th day following UL value of the average frequency corresponded to source (16,6±1,2 Hz and 23,6±1,7Hz.We discussed particularities of the process to compensations and functional importance got result.

  13. Selective Expression of β Tubulin Isotypes in Gerbil Vestibular Sensory Epithelia and Neurons

    Perry, Brian; Jensen–Smith, Heather C.; Ludueña, Richard F.; Hallworth, Richard

    2003-01-01

    The seven mammalian isotypes of β tubulin are strikingly similar in amino acid sequence. The differences in isotypic sequence, although small, are nonetheless conserved in evolution, which suggests that they may confer distinct functional roles. If so, such roles should be reflected in the selective expression of isotypes by cell type, or even in the sorting of isotypes to within-cell pools. Hair cells of the vestibular sensory epithelia each possess a kinocilium, a microtubule-based organell...

  14. Neuronal classification and marker gene identification via single-cell expression profiling of brainstem vestibular neurons subserving cerebellar learning

    Kodama, Takashi; Guerrero, Shiloh; Shin, Minyoung; Moghadam, Seti; Faulstich, Michael; du Lac, Sascha

    2012-01-01

    Identification of marker genes expressed in specific cell types is essential for the genetic dissection of neural circuits. Here we report a new strategy for classifying heterogeneous populations of neurons into functionally distinct types and for identifying associated marker genes. Quantitative single-cell expression profiling of genes related to neurotransmitters and ion channels enables functional classification of neurons; transcript profiles for marker gene candidates identify molecular...

  15. VESTIBULAR REHABILITATION

    Maksim Valer'evich Zamergrad

    2009-06-01

    Full Text Available Vestibular disorders are a frequent abnormality that physicians of various specialties have to encounter. Vestibular and equilibrium disorders are particularly common in elderly patients. In this case they are frequently a cause of falls and various injuries. Vestibular rehabilitation is the most important component of treatment for vestibular and equilibrium disorders. The paper considers the basic mechanisms of vestibular compensation, discusses vestibular rehabilitation procedures by doing routine exercises and by using various biofeedback crunches. In particular, it describes the principle of operation of a posturography platform, a SwayStar system for the diagnosis and therapy of vestibular disorders, and a Brainport device for vestibular rehabilitation. The current methods for drug stimulation of vestibular compensation are discussed. Vestibular rehabilitation used in the complex therapy of equilibrium disorders is stressed to considerably enhance therapeutic effectiveness, to cause a reduction in the risk of falls, and to increase quality of life in patients with vestibular disorders

  16. Modelling the firing pattern of bullfrog vestibular neurons responding to naturalistic stimuli

    Paulin, M. G.; Hoffman, L. F.

    1999-01-01

    We have developed a neural system identification method for fitting models to stimulus-response data, where the response is a spike train. The method involves using a general nonlinear optimisation procedure to fit models in the time domain. We have applied the method to model bullfrog semicircular canal afferent neuron responses during naturalistic, broad-band head rotations. These neurons respond in diverse ways, but a simple four parameter class of models elegantly accounts for the various types of responses observed. c1999 Elsevier Science B.V. All rights reserved.

  17. Uptake of gentamicin by vestibular efferent neurons and superior olivary complex after transtympanic administration in guinea pigs

    Zhang, Yi-Bo; Zhang, Ru; Zhang, Wei-Feng; Peter S. Steyger; Dai, Chun-Fu

    2011-01-01

    Transtympanic administration of gentamicin is a widely accepted and effective approach for treating patients with intractable vertigo. Previous studies have demonstrated the uptake, distribution and effects of gentamicin in peripheral vestibular and cochlear structures after transtympanic injection. However, little is known about whether transtympanically administered gentamicin is trafficked into more central auditory and vestibular structures and its effect on these structures. In this stud...

  18. Vestibular migraine

    Lempert, Thomas; Olesen, Jes; Furman, Joseph;

    2012-01-01

    This paper presents diagnostic criteria for vestibular migraine, jointly formulated by the Committee for Classification of Vestibular Disorders of the Bárány Society and the Migraine Classification Subcommittee of the International Headache Society (IHS). The classification includes vestibular...... migraine and probable vestibular migraine. Vestibular migraine will appear in an appendix of the third edition of the International Classification of Headache Disorders (ICHD) as a first step for new entities, in accordance with the usual IHS procedures. Probable vestibular migraine may be included...... in a later version of the ICHD, when further evidence has been accumulated. The diagnosis of vestibular migraine is based on recurrent vestibular symptoms, a history of migraine, a temporal association between vestibular symptoms and migraine symptoms and exclusion of other causes of vestibular symptoms...

  19. Model Vestibular Nuclei Neurons Can Exhibit a Boosting Nonlinearity Due to an Adaptation Current Regulated by Spike-Triggered Calcium and Calcium-Activated Potassium Channels

    Schneider, Adam D.

    2016-01-01

    In vitro studies have previously found a class of vestibular nuclei neurons to exhibit a bidirectional afterhyperpolarization (AHP) in their membrane potential, due to calcium and calcium-activated potassium conductances. More recently in vivo studies of such vestibular neurons were found to exhibit a boosting nonlinearity in their input-output tuning curves. In this paper, a Hodgkin-Huxley (HH) type neuron model, originally developed to reproduce the in vitro AHP, is shown to produce a boosting nonlinearity similar to that seen in vivo for increased the calcium conductance. Indicative of a bifurcation, the HH model is reduced to a generalized integrate-and-fire (IF) model that preserves the bifurcation structure and boosting nonliearity. By then projecting the neuron model’s phase space trajectories into 2D, the underlying geometric mechanism relating the AHP and boosting nonlinearity is revealed. Further simplifications and approximations are made to derive analytic expressions for the steady steady state firing rate as a function of bias current, μ, as well as the gain (i.e. its slope) and the position of its peak at μ = μ*. Finally, although the boosting nonlinearity has not yet been experimentally observed in vitro, testable predictions indicate how it might be found. PMID:27427914

  20. Spatial coordination by descending vestibular signals. 2. Response properties of medial and lateral vestibulospinal tract neurons in alert and decerebrate cats.

    Iwamoto, Y; Perlmutter, S I; Baker, J F; Peterson, B W

    1996-02-01

    neurons, particularly those with MADs close to the roll axis, may be involved in the vestibular-limb reflex. The combination of vertical and ipsilateral horizontal canal input on many secondary MVST neurons suggests a contribution to the vestibulocollic reflex. However, in contrast to most neck muscles, very few neurons had maximum vertical responses near pitch. PMID:8721157

  1. Fos expression in neurons of the rat vestibulo-autonomic pathway activated by sinusoidal galvanic vestibular stimulation

    GayRHolstein

    2012-01-01

    The vestibular system sends projections to brainstem autonomic nuclei that modulate heart rate and blood pressure in response to changes in head and body position with regard to gravity. Consistent with this, binaural sinusoidal galvanic vestibular stimulation (sGVS) in humans causes vasoconstriction in the legs, while low frequency (0.02-0.04 Hz) sGVS causes a rapid drop in heart rate and blood pressure in anesthetized rats. We have hypothesized that these responses occur through activation ...

  2. Vestibular Hyperacusis

    ... is a Top Rated Nonprofit! Volunteer. Donate. Review. Vestibular Hyperacusis Are you sensitive to certain sounds? Hyperacusis ... parade to a person with hyperacusis. Cochlear vs. vestibular hyperacusis With cochlear hyperacusis, subjects feel ear pain, ...

  3. Fos Expression in Neurons of the Rat Vestibulo-Autonomic Pathway Activated by Sinusoidal Galvanic Vestibular Stimulation

    Holstein, Gay R.; Friedrich Jr., Victor L.; Martinelli, Giorgio P.; Ogorodnikov, Dmitri; Yakushin, Sergei B.; Cohen, Bernard

    2012-01-01

    The vestibular system sends projections to brainstem autonomic nuclei that modulate heart rate and blood pressure in response to changes in head and body position with regard to gravity. Consistent with this, binaural sinusoidally modulated galvanic vestibular stimulation (sGVS) in humans causes vasoconstriction in the legs, while low frequency (0.02–0.04 Hz) sGVS causes a rapid drop in heart rate and blood pressure in anesthetized rats. We have hypothesized that these responses occur through...

  4. Heterotrimeric guanosine triphosphate-binding protein-coupled modulatory actions of motilin on K+ channels and postsynaptic γ-aminobutyric acid receptors in mouse medial vestibular nuclear neurons.

    Todaka, Hiroshi; Tatsukawa, Tetsuya; Hashikawa, Tsutomu; Yanagawa, Yuchio; Shibuki, Katsuei; Nagao, Soichi

    2013-02-01

    Some central nervous system neurons express receptors of gastrointestinal hormones, but their pharmacological actions are not well known. Previous anatomical and unit recording studies suggest that a group of cerebellar Purkinje cells express motilin receptors, and motilin depresses the spike discharges of vestibular nuclear neurons that receive direct cerebellar inhibition in rats or rabbits. Here, by the slice-patch recording method, we examined the pharmacological actions of motilin on the mouse medial vestibular nuclear neurons (MVNs), which play an important role in the control of ocular reflexes. A small number of MVNs, as well as cerebellar floccular Purkinje cells, were labeled with an anti-motilin receptor antibody. Bath application of motilin (0.1 μm) decreased the discharge frequency of spontaneous action potentials in a group of MVNs in a dose-dependent manner (K(d) , 0.03 μm). The motilin action on spontaneous action potentials was blocked by apamin (100 nm), a blocker of small-conductance Ca(2+) -activated K(+) channels. Furthermore, motilin enhanced the amplitudes of inhibitory postsynaptic currents (IPSCs) and miniature IPSCs, but did not affect the frequencies of miniature IPSCs. Intracellular application of pertussis toxin (PTx) (0.5 μg/μL) or guanosine triphosphate-γ-S (1 mm) depressed the motilin actions on both action potentials and IPSCs. Only 30% of MVNs examined on slices obtained from wild-type mice, but none of the GABAergic MVNs that were studied on slices obtained from vesicular γ-aminobutyric acid transporter-Venus transgenic mice, showed such a motilin response on action potentials and IPSCs. These findings suggest that motilin could modulate small-conductance Ca(2+) -activated K(+) channels and postsynaptic γ-aminobutyric acid receptors through heterotrimeric guanosine triphosphate-binding protein-coupled receptor in a group of glutamatergic MVNs. PMID:23136934

  5. Activation of µ-opioid receptors inhibits calcium-currents in the vestibular afferent neurons of the rat through a cAMP dependent mechanism

    Enrique Soto

    2014-03-01

    Full Text Available Opioid receptors are expressed in the vestibular endorgans (afferent neurons and hair cells and are activated by the efferent system, which modulates the discharge of action potentials in the vestibular afferent neurons (VANs. In mammals, the VANs mainly express the µ opioid-receptor, but the function of the opioid receptor activation and the cellular mechanisms by which they exert their actions in these neurons are poorly studied. To determine the actions of the µ opioid receptor (MOR and the cell signaling mechanisms in the VANs, we made perforated patch-clamp recordings of VANs that were obtained from postnatal days 7 to 10 (P7-10 rats and then maintained in primary culture. The MOR agonist [D-Ala2, N-Me-Phe4, Gly5-ol]-enkephalin (DAMGO inhibited the total voltage-gated outward current; this effect was prevented by the perfusion of a Ca2+-free extracellular solution. We then studied the voltage-gated calcium current (Ica and found that DAMGO Met-enkephalin or endomorphine-1 inhibited the ICa in a dose-response fashion. The effects of DAMGO were prevented by the MOR antagonist (CTAP or by the pertussis toxin (PTX. The use of specific calcium channel blockers showed that MOR activation inhibited the T-, L- and N-type ICa. The use of various enzyme activators and inhibitors and of cAMP analogs allowed us to demonstrate that the MOR acts through a cAMP dependent signaling mechanism. In the current clamp experiments, MOR activation increased the duration and decreased the amplitude of the action potentials and modulated the discharge to the current injection. Pre-incubation with PTX occluded all MOR activation effects observed in the current clamp experiments.\tWe conclude that MOR activation inhibits the T-, L- and N-type ICa through the activation of a Gi/o protein that involves a decrease in AC-cAMP-PKA activity. The modulation of ICa may have an impact on the synaptic integration, excitability and neurotransmitter release from the VANs.

  6. ACTIVITY OF THE SUPERIOR VESTIBULAR NUCLEI NEURONS AT STIMULATION OF HYPOTHALAMIC PARAVENTRICULAR AND SUPRAOPTIC NUCLEI IN CONDITIONS OF UNILATERAL LABYRINTHECTOMY COMBINED WITH VIBRATION EXPOSURE

    S.H. Sarkisyan

    2010-05-01

    Full Text Available We studied the frequency changes of single neuronal spike activity flow from superior vestibular nucleus (SVN, evoked on high frequency stimulation (HFS of paraventricular (PV and supraoptic (SO nuclei of hypothalamus in Albino rats in conditions of unilateral labyrinthectomy (UL combined with many days of vibration exposure (VE. Programmed mathematical on-linе analysis was used. In normal conditions, at bilateral stimulation of PV and SO nuclei the tetanic potentiation (TP prevaled. After UL in control at uninjured side TP and posttetanic potentiation (PTP were recorded; on injured side, on the whole, along with variability of initial background activity of SVN neurons, an exiguity of components and of the repeatability of poststimulus excitatory and inhibitory manifestations of SVN neurons’ activity were recorded. Combined action of UL and VE at intact side evoked tetanic depression on ipsilateral stimulation of PV and SO nuclei; on injured side the stimulation of the same nuclei evoked TP and PTP, which achieved normal levels. The results of histochemical investigation in analogous experimental conditions confirmed the electrophysiological data, which allowed us concluding about protective effect of VE.

  7. Molecular aging of the mammalian vestibular system.

    Brosel, Sonja; Laub, Christoph; Averdam, Anne; Bender, Andreas; Elstner, Matthias

    2016-03-01

    Dizziness and imbalance frequently affect the elderly and contribute to falls and frailty. In many geriatric patients, clinical testing uncovers a dysfunction of the vestibular system, but no specific etiology can be identified. Neuropathological studies have demonstrated age-related degeneration of peripheral and central vestibular neurons, but the molecular mechanisms are poorly understood. In contrast, recent studies into age-related hearing loss strongly implicate mitochondrial dysfunction, oxidative stress and apoptotic cell death of cochlear hair cells. While some data suggest that analogous biological pathomechanisms may underlie vestibular dysfunction, actual proof is missing. In this review, we summarize the available data on the molecular causes of vestibular dysfunction. PMID:26739358

  8. What galvanic vestibular stimulation actually activates

    IanSCurthoys

    2012-01-01

    In a recent paper in Frontiers Cohen et al. (2012) asked “What does galvanic vestibular stimulation actually activate?” and concluded that galvanic vestibular stimulation (GVS) causes predominantly otolithic behavioural responses. In this Perspective paper we show that such a conclusion does not follow from the evidence. The evidence from neurophysiology is very clear: galvanic stimulation activates primary otolithic neurons as well as primary semicircular canal neurons (Kim and Curthoys,...

  9. Balance (or Vestibular) Rehabilitation

    ... for the Public / Hearing and Balance Balance (or Vestibular) Rehabilitation Audiologic (hearing), balance, and medical diagnostic tests help indicate whether you are a candidate for vestibular (balance) rehabilitation. Vestibular rehabilitation is an individualized balance ...

  10. Rehabilitation in vestibular system diseases

    Maksim Valeryevich Zamergrad

    2013-01-01

    Vestibular rehabilitation is an important component of combination treatment in a patient with vertigo. Vestibular rehabilitation is indicated for different diseases of the central or peripheral vestibular system. The goal of vestibular rehabilitation is to ensure gaze stabilization, to train postural stability, and to reduce subjective vertigo. Vestibular rehabilitation is based on the stimulation of vestibular adaptation, sensory substitution, and habituation. Vestibular suppressants, inade...

  11. CONTRIBUTION OF THE AUDIOLOGICAL AND VESTIBULAR ASSESSMENT TO THE DIFFERENTIAL AND ETIOLOGICAL DIAGNOSIS OF PERIPHERIC VESTIBULAR SYNDROMES

    Loreta Ungureanu

    2012-09-01

    Full Text Available Scope of the study: Vestibular pathology is a complex one, requiring a minute clinical evaluation, as well as numerous paraclinical investigations. The present study analyzes the contribution of the modern methods of vestibular and auditive investigation to the diagnosis of dizziness. Materials and method: The results of the investigations performed on 84 patients with peripheric vestibular syndrome, on whom a complete audiological and vestibular assessment had been also made, have been retrospectively analyzed. Results: Anamnestic data and the results of evaluation permitted classification of peripheric vestibular pathology according to topo-lesional and etiological criteria. The most frequently diagnosed diseases were: benign paroxysmal positional vertigo, Ménière syndrome and vestibular neuronitis. Conclusions: Testing of the vestibulo-ocular and vestibulo-spinal reflexes through videonystagmoscopy and, respectively, computerized dynamic posturography, besides tonal vocal audiometry and precocious auditive potentials, is especially important for a positive diagnosis and etiological differentiation of vestibular syndromes.

  12. Peripheral Vestibular System Disease in Vestibular Schwannomas

    Møller, Martin Nue; Hansen, Søren; Caye-Thomasen, Per

    2015-01-01

    that this may be caused by both cochlear and retrocochlear mechanisms. Multiple mechanisms may also be at play in the case of dizziness, which may broaden perspectives of therapeutic approach. This study presents a systematic and detailed assessment of vestibular histopathology in temporal bones from patients...... with VS. METHODS: Retrospective analysis of vestibular system histopathology in temporal bones from 17 patients with unilateral VS. The material was obtained from The Copenhagen Temporal Bone Collection. RESULTS: Vestibular schwannomas were associated with atrophy of the vestibular ganglion, loss of fiber...... density of the peripheral vestibular nerve branches, and atrophy of the neuroepithelium of the vestibular end organs. In cases with small tumors, peripheral disease occurred only in the tissue structures innervated by the specific nerve from which the tumor originated. CONCLUSION: Vestibular schwannomas...

  13. Rehabilitation in vestibular system diseases

    Maksim Valeryevich Zamergrad

    2013-03-01

    Full Text Available Vestibular rehabilitation is an important component of combination treatment in a patient with vertigo. Vestibular rehabilitation is indicated for different diseases of the central or peripheral vestibular system. The goal of vestibular rehabilitation is to ensure gaze stabilization, to train postural stability, and to reduce subjective vertigo. Vestibular rehabilitation is based on the stimulation of vestibular adaptation, sensory substitution, and habituation. Vestibular suppressants, inadequate mobility, anxiety, and depression decelerate vestibular compensation whereas early activation, mobility, and betaserc use accelerate it.

  14. Procedures for restoring vestibular disorders

    Walther, Leif Erik

    2005-09-01

    Full Text Available This paper will discuss therapeutic possibilities for disorders of the vestibular organs and the neurons involved, which confront ENT clinicians in everyday practice. Treatment of such disorders can be tackled either symptomatically or causally. The possible strategies for restoring the body's vestibular sense, visual function and co-ordination include medication, as well as physical and surgical procedures. Prophylactic or preventive measures are possible in some disorders which involve vertigo (bilateral vestibulopathy, kinetosis, height vertigo, vestibular disorders when diving (Tables 1 and 2. Glucocorticoid and training therapy encourage the compensation of unilateral vestibular loss. In the case of a bilateral vestibular loss, it is important to treat the underlying disease (e.g. Cogan's disease. Although balance training does improve the patient's sense of balance, it will not restore it completely.In the case of Meniere's disease, there are a number of medications available to either treat bouts or to act as a prophylactic (e.g. dimenhydrinate or betahistine. In addition, there are non-ablative (sacculotomy as well as ablative surgical procedures (e.g. labyrinthectomy, neurectomy of the vestibular nerve. In everyday practice, it has become common to proceed with low risk therapies initially. The physical treatment of mild postural vertigo can be carried out quickly and easily in outpatients (repositioning or liberatory maneuvers. In very rare cases it may be necessary to carry out a semicircular canal occlusion. Isolated disturbances of the otolith function or an involvement of the otolith can be found in roughly 50% of labyrinth disturbances. A specific surgical procedure to selectively block the otolith organs is currently being studied. When an external perilymph fistula involving loss of perilymph is suspected, an exploratory tympanotomy involving also the round and oval window niches must be carried out. A traumatic rupture of the

  15. Electrical vestibular stimulation after vestibular deafferentation and in vestibular schwannoma.

    Swee Tin Aw

    Full Text Available BACKGROUND: Vestibular reflexes, evoked by human electrical (galvanic vestibular stimulation (EVS, are utilized to assess vestibular function and investigate its pathways. Our study aimed to investigate the electrically-evoked vestibulo-ocular reflex (eVOR output after bilateral and unilateral vestibular deafferentations to determine the characteristics for interpreting unilateral lesions such as vestibular schwannomas. METHODS: EVOR was recorded with dual-search coils as binocular three-dimensional eye movements evoked by bipolar 100 ms-step at EVS intensities of [0.9, 2.5, 5.0, 7.5, 10.0] mA and unipolar 100 ms-step at 5 mA EVS intensity. Five bilateral vestibular deafferented (BVD, 12 unilateral vestibular deafferented (UVD, four unilateral vestibular schwannoma (UVS patients and 17 healthy subjects were tested with bipolar EVS, and five UVDs with unipolar EVS. RESULTS: After BVD, bipolar EVS elicited no eVOR. After UVD, bipolar EVS of one functioning ear elicited bidirectional, excitatory eVOR to cathodal EVS with 9 ms latency and inhibitory eVOR to anodal EVS, opposite in direction, at half the amplitude with 12 ms latency, exhibiting an excitatory-inhibitory asymmetry. The eVOR patterns from UVS were consistent with responses from UVD confirming the vestibular loss on the lesion side. Unexpectedly, unipolar EVS of the UVD ear, instead of absent response, evoked one-third the bipolar eVOR while unipolar EVS of the functioning ear evoked half the bipolar response. CONCLUSIONS: The bidirectional eVOR evoked by bipolar EVS from UVD with an excitatory-inhibitory asymmetry and the 3 ms latency difference between normal and lesion side may be useful for detecting vestibular lesions such as UVS. We suggest that current spread could account for the small eVOR to 5 mA unipolar EVS of the UVD ear.

  16. Types of Vestibular Disorders

    ... CANVAS is an easy to remember acronym for cerebellar ataxia, neuropathy, and vestibular areflexia. There are only a ... the requisite combination of two rare clinical findings (cerebellar ataxia and vestibular areflexia), and the very common peripheral ...

  17. Vestibular Disorders Association

    ... How do I know if I have a vestibular disorder?" Find out more about the symptoms of ... find a doctor with a special interest in vestibular disorders." Click here to search our provider directory. ...

  18. Differential central projections of vestibular afferents in pigeons

    Dickman, J. D.; Fang, Q.

    1996-01-01

    The question of whether a differential distribution of vestibular afferent information to central nuclear neurons is present in pigeons was studied using neural tracer compounds. Discrete tracing of afferent fibers innervating the individual semicircular canal and otolith organs was produced by sectioning individual branches of the vestibular nerve that innervate the different receptor organs and applying crystals of horseradish peroxidase, or a horseradish peroxidase/cholera toxin mixture, or a biocytin compound for neuronal uptake and transport. Afferent fibers and their terminal distributions within the brainstem and cerebellum were visualized subsequently. Discrete areas in the pigeon central nervous system that receive primary vestibular input include the superior, dorsal lateral, ventral lateral, medial, descending, and tangential vestibular nuclei; the A and B groups; the intermediate, medial, and lateral cerebellar nuclei; and the nodulus, the uvula, and the paraflocculus. Generally, the vertical canal afferents projected heavily to medial regions in the superior and descending vestibular nuclei as well as the A group. Vertical canal projections to the medial and lateral vestibular nuclei were observed but were less prominent. Horizontal canal projections to the superior and descending vestibular nuclei were much more centrally located than those of the vertical canals. A more substantial projection to the medial and lateral vestibular nuclei was seen with horizontal canal afferents compared to vertical canal fibers. Afferents innervating the utricle and saccule terminated generally in the lateral regions of all vestibular nuclei in areas that were separate from the projections of the semicircular canals. In addition, utricular fibers projected to regions in the vestibular nuclei that overlapped with the horizontal semicircular canal terminal fields, whereas saccular afferents projected to regions that received vertical canal fiber terminations. Lagenar

  19. Specific vestibular exercises in the treatment of vestibular neuritis

    Komazec Zoran; Lemajić Slobodanka N.

    2004-01-01

    Introduction Vestibular neuritis rapidly damages unilateral vestibular periphery, inducing severe balance disorders. In most cases, such vestibular imbalance is gradually restored to within the normal level after clinical therapies. This successive clinical recovery occurs due to regeneration of vestibular periphery and/or accomplishment of central vestibular compensation. Rehabilitation The program of vestibular rehabilitation presents a major achievement in the field of treatment of balance...

  20. Surgical Procedures for Vestibular Dysfunction

    ... Rated Nonprofit! Volunteer. Donate. Review. Surgical Procedures for Vestibular Dysfunction When is surgery necessary? When medical treatment ... organ (cochlea) is also sacrificed with this procedure. Vestibular nerve section A vestibular nerve section is a ...

  1. What galvanic vestibular stimulation actually activates

    Ian S Curthoys

    2012-07-01

    Full Text Available In a recent paper in Frontiers Cohen et al. (2012 asked What does galvanic vestibular stimulation actually activate? and concluded that galvanic vestibular stimulation (GVS causes predominantly otolithic behavioural responses. In this Perspective paper we show that such a conclusion does not follow from the evidence. The evidence from neurophysiology is very clear: galvanic stimulation activates primary otolithic neurons as well as primary semicircular canal neurons (Kim and Curthoys, 2004. Irregular neurons are activated at lower currents. The answer to what behaviour is activated depends on what is measured and how it is measured, including not just technical details, such as the frame rate of video, but the exact experimental context in which the measurement took place (visual fixation vs total darkness. Both canal and otolith dependent responses are activated by GVS.

  2. Vestibular perception following acute unilateral vestibular lesions.

    Sian Cousins

    Full Text Available Little is known about the vestibulo-perceptual (VP system, particularly after a unilateral vestibular lesion. We investigated vestibulo-ocular (VO and VP function in 25 patients with vestibular neuritis (VN acutely (2 days after onset and after compensation (recovery phase, 10 weeks. Since the effect of VN on reflex and perceptual function may differ at threshold and supra-threshold acceleration levels, we used two stimulus intensities, acceleration steps of 0.5°/s(2 and velocity steps of 90°/s (acceleration 180°/s(2. We hypothesised that the vestibular lesion or the compensatory processes could dissociate VO and VP function, particularly if the acute vertiginous sensation interferes with the perceptual tasks. Both in acute and recovery phases, VO and VP thresholds increased, particularly during ipsilesional rotations. In signal detection theory this indicates that signals from the healthy and affected side are still fused, but result in asymmetric thresholds due to a lesion-induced bias. The normal pattern whereby VP thresholds are higher than VO thresholds was preserved, indicating that any 'perceptual noise' added by the vertigo does not disrupt the cognitive decision-making processes inherent to the perceptual task. Overall, the parallel findings in VO and VP thresholds imply little or no additional cortical processing and suggest that vestibular thresholds essentially reflect the sensitivity of the fused peripheral receptors. In contrast, a significant VO-VP dissociation for supra-threshold stimuli was found. Acutely, time constants and duration of the VO and VP responses were reduced - asymmetrically for VO, as expected, but surprisingly symmetrical for perception. At recovery, VP responses normalised but VO responses remained shortened and asymmetric. Thus, unlike threshold data, supra-threshold responses show considerable VO-VP dissociation indicative of additional, higher-order processing of vestibular signals. We provide evidence of

  3. Vestibular Compensation in Unilateral Patients Often Causes Both Gain and Time Constant Asymmetries in the VOR.

    Ranjbaran, Mina; Katsarkas, Athanasios; Galiana, Henrietta L

    2016-01-01

    The vestibulo-ocular reflex (VOR) is essential in our daily life to stabilize retinal images during head movements. Balanced vestibular functionality secures optimal reflex performance which otherwise can be distorted by peripheral vestibular lesions. Luckily, vestibular compensation in different neuronal sites restores VOR function to some extent over time. Studying vestibular compensation gives insight into the possible mechanisms for plasticity in the brain. In this work, novel experimental analysis tools are employed to reevaluate the VOR characteristics following unilateral vestibular lesions and compensation. Our results suggest that following vestibular lesions, asymmetric performance of the VOR is not only limited to its gain. Vestibular compensation also causes asymmetric dynamics, i.e., different time constants for the VOR during leftward or rightward passive head rotation. Potential mechanisms for these experimental observations are provided using simulation studies. PMID:27065839

  4. Specific vestibular exercises in the treatment of vestibular neuritis

    Komazec Zoran

    2004-01-01

    Full Text Available Introduction Vestibular neuritis rapidly damages unilateral vestibular periphery, inducing severe balance disorders. In most cases, such vestibular imbalance is gradually restored to within the normal level after clinical therapies. This successive clinical recovery occurs due to regeneration of vestibular periphery and/or accomplishment of central vestibular compensation. Rehabilitation The program of vestibular rehabilitation presents a major achievement in the field of treatment of balance disorders. Vestibular compensation is associated with central sensory reintegration and bilaterally equalizes the vestibular tonus over a period of time. Material and methods In this retrospective study of a series of cases authors present their results in 58 patients undergoing a program of vestibular rehabilitation. Patients were divided into two groups. Thirty patients were in group I, and 28 in group II. Specific vestibular exercises were conducted in group I, and non-specific exercises in group II. Analysis of effects of vestibular compensation was made due electronystagmography. Results Results were satisfactory in both groups of patients. Absence of spontaneous nystagmus was detected in 83.3% of patients in group I (specific vestibular exercises and in 53.5% of patients in group II (non-specific exercises, with an average treatment time of up to 2 months. Harmonization of pendular stimulation was detected in 83.3% and 60.7% of patients in groups I and II, respectively. Conclusion Early physiotherapeutic vestibular rehabilitation supports the vestibular compensation mechanism. At the same time vestibular rehabilitation may prevent panic disorder caused by hyperventilation syndrome.

  5. Vestibular pathways involved in cognition

    Martin Hitier

    2014-01-01

    Recent discoveries have emphasized the role of the vestibular system in cognitive processes such as memory, spatial navigation and bodily self-consciousness. A precise understanding of the vestibular pathways involved is essential to understand the consequences of vestibular diseases for cognition, as well as develop therapeutic strategies to facilitate recovery. The knowledge of the “vestibular cortical projections areas”, defined as the cortical areas activated by vestibular stimulation, ha...

  6. Vestibular control of body orientation in lamprey

    Pavlova, Elena

    2004-01-01

    Maintenance of body orientation (postural control) is a vital motor function of the brain. The general goal of this project was to understand the organization and operation of neuronal networks responsible for postural control. The lamprey (a lower vertebrate) was used as a model animal. The postural control system in the lamprey, driven by vestibular input, maintains a definite orientation of the longitudinal body axis in relation to horizon (pitch angle) and the dorsal-sid...

  7. Computational Approaches to Vestibular Research

    Ross, Muriel D.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    The Biocomputation Center at NASA Ames Research Center is dedicated to a union between computational, experimental and theoretical approaches to the study of neuroscience and of life sciences in general. The current emphasis is on computer reconstruction and visualization of vestibular macular architecture in three-dimensions (3-D), and on mathematical modeling and computer simulation of neural activity in the functioning system. Our methods are being used to interpret the influence of spaceflight on mammalian vestibular maculas in a model system, that of the adult Sprague-Dawley rat. More than twenty 3-D reconstructions of type I and type II hair cells and their afferents have been completed by digitization of contours traced from serial sections photographed in a transmission electron microscope. This labor-intensive method has now been replace d by a semiautomated method developed in the Biocomputation Center in which conventional photography is eliminated. All viewing, storage and manipulation of original data is done using Silicon Graphics workstations. Recent improvements to the software include a new mesh generation method for connecting contours. This method will permit the investigator to describe any surface, regardless of complexity, including highly branched structures such as are routinely found in neurons. This same mesh can be used for 3-D, finite volume simulation of synapse activation and voltage spread on neuronal surfaces visualized via the reconstruction process. These simulations help the investigator interpret the relationship between neuroarchitecture and physiology, and are of assistance in determining which experiments will best test theoretical interpretations. Data are also used to develop abstract, 3-D models that dynamically display neuronal activity ongoing in the system. Finally, the same data can be used to visualize the neural tissue in a virtual environment. Our exhibit will depict capabilities of our computational approaches and

  8. A Recipe for Bidirectional Motor Learning: Using Inhibition to Cook Plasticity in the Vestibular Nuclei

    Medina, Javier F.

    2010-01-01

    In this issue of Neuron, McElvain et al. demonstrate for the first time plasticity at the synapse between vestibular nerve afferents and their postsynaptic targets in the medial vestibular nuclei. This new type of plasticity, which is gated by inhibition, is well suited to drive motor learning during adaptation of the vestibulo-ocular reflex.

  9. Distinct vestibular effects on early and late somatosensory cortical processing in humans

    C. Pfeiffer; M. van Elk; F. Bernasconi; O. Blanke

    2016-01-01

    In non-human primates several brain areas contain neurons that respond to both vestibular and somatosensory stimulation. In humans, vestibular stimulation activates several somatosensory brain regions and improves tactile perception. However, less is known about the spatio-temporal dynamics of such

  10. Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Vestibular Schwannoma (Acoustic Neuroma) and Neurofibromatosis On this page: ... more information about vestibular schwannomas? What is a vestibular schwannoma (acoustic neuroma)? Inner ear with vestibular schwannoma ( ...

  11. Vestibular compensation: the neuro-otologist's best friend.

    Lacour, Michel; Helmchen, Christoph; Vidal, Pierre-Paul

    2016-04-01

    Why vestibular compensation (VC) after an acute unilateral vestibular loss is the neuro-otologist's best friend is the question at the heart of this paper. The different plasticity mechanisms underlying VC are first reviewed, and the authors present thereafter the dual concept of vestibulo-centric versus distributed learning processes to explain the compensation of deficits resulting from the static versus dynamic vestibular imbalance. The main challenges for the plastic events occurring in the vestibular nuclei (VN) during a post-lesion critical period are neural protection, structural reorganization and rebalance of VN activity on both sides. Data from animal models show that modulation of the ipsilesional VN activity by the contralateral drive substitutes for the normal push-pull mechanism. On the other hand, sensory and behavioural substitutions are the main mechanisms implicated in the recovery of the dynamic functions. These newly elaborated sensorimotor reorganizations are vicarious idiosyncratic strategies implicating the VN and multisensory brain regions. Imaging studies in unilateral vestibular loss patients show the implication of a large neuronal network (VN, commissural pathways, vestibulo-cerebellum, thalamus, temporoparietal cortex, hippocampus, somatosensory and visual cortical areas). Changes in gray matter volume in these multisensory brain regions are structural changes supporting the sensory substitution mechanisms of VC. Finally, the authors summarize the two ways to improve VC in humans (neuropharmacology and vestibular rehabilitation therapy), and they conclude that VC would follow a "top-down" strategy in patients with acute vestibular lesions. Future challenges to understand VC are proposed. PMID:27083885

  12. [Therapy of vestibular vertigo].

    Hamann, K F

    1993-05-01

    The non-surgical treatment of vestibular disorders must be based on current knowledge of vestibular pathophysiology. It is generally accepted that after vestibular lesions a self-repair mechanism exists that allows a more or less complete recovery. In cases of persisting vestibular complaints the physician's duty consists in stimulation of these pre-existing mechanisms. This can be done by physical exercises, as has been recommended since the work of Cawthorne and Cooksey in 1946. This concept is meanwhile supported by modern neurophysiological research. This article describes a short training program consisting of exercises for fixation during rotations, smooth pursuit, optokinetic nystagmus and motor learning mechanisms. Physical exercises can be reinforced by nootropic drugs. PMID:8335490

  13. Angiogenesis in vestibular schwannomas

    Møller, Martin Nue; Werther, Kim; Nalla, Amarnadh;

    2010-01-01

    Vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) are potent mediators of tumor angiogenesis. It has been demonstrated that vestibular schwannoma VEGF expression correlates with tumor growth pattern, whereas knowledge on the expression of MMPs is lacking. This study...

  14. Vertigo and vestibular rehabilitation.

    Konnur M

    2000-01-01

    The role of rehabilitation in the management of vertigo is limited to a very specific group of conditions. An Occupational therapist who is a part of the multidisciplinary team treating the vertiginous patient, with the knowledge of physiology and therapeutic benefit of vestibular rehabilitation can widen the rehabilitation spectrum for various diseases producing vertigo and dysequilibrium, to resolve or minimise these symptoms. The present article reviews the need for vestibular rehabilitati...

  15. Vestibular function testing.

    Lang, E E

    2010-06-01

    Vestibular symptoms of vertigo, dizziness and dysequilibrium are common complaints which can be disabling both physically and psychologically. Routine examination of the ear nose and throat and neurological system are often normal in these patients. An accurate history and thorough clinical examination can provide a diagnosis in the majority of patients. However, in a subgroup of patients, vestibular function testing may be invaluable in arriving at a correct diagnosis and ultimately in the optimal treatment of these patients.

  16. Deregulated genes in sporadic vestibular schwannomas

    Cayé-Thomasen, Per; Helweg-Larsen, Rehannah Holga Andrea; Stangerup, Sven-Eric;

    2010-01-01

    In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology.......In search of genes associated with vestibular schwannoma tumorigenesis, this study examines the gene expression in human vestibular nerve versus vestibular schwannoma tissue samples using microarray technology....

  17. Glutamate and GABA in Vestibulo-Sympathetic Pathway Neurons.

    Holstein, Gay R; Friedrich, Victor L; Martinelli, Giorgio P

    2016-01-01

    The vestibulo-sympathetic reflex (VSR) actively modulates blood pressure during changes in posture. This reflex allows humans to stand up and quadrupeds to rear or climb without a precipitous decline in cerebral perfusion. The VSR pathway conveys signals from the vestibular end organs to the caudal vestibular nuclei. These cells, in turn, project to pre-sympathetic neurons in the rostral and caudal ventrolateral medulla (RVLM and CVLM, respectively). The present study assessed glutamate- and GABA-related immunofluorescence associated with central vestibular neurons of the VSR pathway in rats. Retrograde FluoroGold tract tracing was used to label vestibular neurons with projections to RVLM or CVLM, and sinusoidal galvanic vestibular stimulation (GVS) was employed to activate these pathways. Central vestibular neurons of the VSR were identified by co-localization of FluoroGold and cFos protein, which accumulates in some vestibular neurons following galvanic stimulation. Triple-label immunofluorescence was used to co-localize glutamate- or GABA- labeling in the identified VSR pathway neurons. Most activated projection neurons displayed intense glutamate immunofluorescence, suggestive of glutamatergic neurotransmission. To support this, anterograde tracer was injected into the caudal vestibular nuclei. Vestibular axons and terminals in RVLM and CVLM co-localized the anterograde tracer and vesicular glutamate transporter-2 signals. Other retrogradely-labeled cFos-positive neurons displayed intense GABA immunofluorescence. VSR pathway neurons of both phenotypes were present in the caudal medial and spinal vestibular nuclei, and projected to both RVLM and CVLM. As a group, however, triple-labeled vestibular cells with intense glutamate immunofluorescence were located more rostrally in the vestibular nuclei than the GABAergic neurons. Only the GABAergic VSR pathway neurons showed a target preference, projecting predominantly to CVLM. These data provide the first

  18. Glutamate and GABA in vestibulo-sympathetic pathway neurons

    Gay R Holstein

    2016-02-01

    Full Text Available The vestibulo-sympathetic reflex actively modulates blood pressure during changes in posture. This reflex allows humans to stand up and quadrupeds to rear or climb without a precipitous decline in cerebral perfusion. The vestibulo-sympathetic reflex pathway conveys signals from the vestibular end organs to the caudal vestibular nuclei. These cells, in turn, project to pre-sympathetic neurons in the rostral and caudal ventrolateral medulla (RVLM and CVLM, respectively. The present study assessed glutamate- and GABA-related immunofluorescence associated with central vestibular neurons of the vestibulo-sympathetic reflex pathway in rats. Retrograde FluoroGold tract tracing was used to label vestibular neurons with projections to RVLM or CVLM, and sinusoidal galvanic vestibular stimulation was employed to activate these pathways. Central vestibular neurons of the vestibulo-sympathetic reflex were identified by co-localization of FluoroGold and cFos protein, which accumulates in some vestibular neurons following galvanic stimulation. Triple-label immunofluorescence was used to co-localize glutamate- or GABA- labeling in the identified vestibulo-sympathetic reflex pathway neurons. Most activated projection neurons displayed intense glutamate immunofluorescence, suggestive of glutamatergic neurotransmission. To support this, anterograde tracer was injected into the caudal vestibular nuclei. Vestibular axons and terminals in RVLM and CVLM co-localized the anterograde tracer and vesicular glutamate transporter-2 signals. Other retrogradely-labeled cFos-positive neurons displayed intense GABA immunofluorescence. Vestibulo-sympathetic reflex pathway neurons of both phenotypes were present in the caudal medial and spinal vestibular nuclei, and projected to both RVLM and CVLM. As a group, however, triple-labeled vestibular cells with intense glutamate immunofluorescence were located more rostrally in the vestibular nuclei than the GABAergic neurons. Only the

  19. Vestibular Rehabilitation Outcomes in the Elderly with Chronic Vestibular Dysfunction

    Bayat, Arash; Pourbakht, Akram; Saki, Nader; Zainun, Zuraida; Nikakhlagh, Soheila; Mirmomeni, Golshan

    2012-01-01

    Background Chronic vestibular dysfunction is a frustrating problem in the elderly and can have a tremendous impact on their life, but only a few studies are available. Vestibular rehabilitation therapy (VRT) is an important therapeutic option for the neuro-otologist in treating patients with significant balance deficits. Objectives The purpose of this study was to assess the effect of vestibular rehabilitation on dizziness in elderly patients with chronic vestibular dysfunction. Materials and...

  20. Vestibular rehabilitation with visual stimuli in peripheral vestibular disorders

    Andréa Manso; Mauricio Malavasi Ganança; Heloisa Helena Caovilla

    2016-01-01

    ABSTRACT INTRODUCTION: Visual stimuli can induce vestibular adaptation and recovery of body balance. OBJECTIVE: To verify the effect of visual stimuli by digital images on vestibular and body balance rehabilitation of peripheral vestibular disorders. METHODS: Clinical, randomized, prospective study. Forty patients aged between 23 and 63 years with chronic peripheral vestibular disorders underwent 12 sessions of rehabilitation with visual stimuli using digital video disk (DVD) (experimental...

  1. Vestibular modulation of spatial perception.

    Ferrè, Elisa R.; Longo, Matthew R.; Fiori, Federico; Haggard, Patrick

    2013-01-01

    Vestibular inputs make a key contribution to the sense of one’s own spatial location. While the effects of vestibular stimulation on visuo-spatial processing in neurological patients have been extensively described, the normal contribution of vestibular inputs to spatial perception remains unclear. To address this issue, we used a line bisection task to investigate the effects of galvanic vestibular stimulation (GVS) on spatial perception, and on the transition between near and far space. Bri...

  2. Vestibular modulation of spatial perception

    Elisa Raffaella Ferre; Matthew Longo; Federico Fiori

    2013-01-01

    Vestibular inputs make a key contribution to the sense of one’s own spatial location. While the effects of vestibular stimulation on visuo-spatial processing in neurological patients have been extensively described, the normal contribution of vestibular inputs to spatial perception remains unclear. To address this issue, we used a line bisection task to investigate the effects of galvanic vestibular stimulation (GVS) on spatial perception, and on the transition between near and far space. ...

  3. Optimal duration of therapy in the recovery period of vestibular diseases

    M. V. Zamergrad

    2014-01-01

    Full Text Available Dizziness is a common symptom in neurological and general medical practice. In most cases it is caused by diseases of the central or peripheral vestibular system. The most common vestibular system diseases include benign paroxysmal postural vertigo, dizziness, Meniere's disease, vestibular neuronitis, and cerebrovascular diseases. One of the main treatments for the diseases accompanied by dizziness is vestibular rehabilitation that is a complex of exercises, the goal of which is to stimulate vestibular compensation. Adequate vestibular compensation allows a patient to get rid of dizziness and unsteadiness even though vestibular system injury is irreversible. Some medications are able to enhance the efficiency of vestibular rehabilitation. At the same time, the optimal duration of treatment for the most common vestibular disorders has not beenadequately explored. The paper gives the results of an observational program, whose purpose was to determine the optimal duration of vestibular rehabilitation in combination with the use of tanakan in patients with non-progressive unilateral peripheral vestibular disorder.Patients and methods. Data on 46 patients aged 19 to 70 years who underwent vestibular rehabilitation and took tanakan for vertigo caused by vestibular neuronitis (n = 44, labyrinthitis (n =1, or Ramsay Hunt syndrome (n = 1 were analyzed. All the patients were examined four times. The symptoms were recorded and the histories of disease were considered. The degree of vestibular disorders, including vertigo, was assessed when collecting complaints. The symptoms of vertigo were objectivized using its vertigo rating scale and five-point subjective rating scale for vertigo. All the patients underwent standard somatic and neurological examinations and videonystagmography. During the first visit after diagnosis, vestibular exercises were chosen for the patients and tanakan was used in a dose of 40 mg thrice daily to accelerate

  4. Modulation of memory by vestibular lesions and galvanic vestibular stimulation

    Paul eSmith

    2010-11-01

    Full Text Available For decades it has been speculated that there is a close association between the vestibular system and spatial memories constructed by areas of the brain such as the hippocampus. While many animal studies have been conducted which support this relationship, only in the last 10 years have detailed quantitative studies been carried out in patients with vestibular disorders. The majority of these studies suggest that complete bilateral vestibular loss results in spatial memory deficits that are not simply due to vestibular reflex dysfunction, while the effects of unilateral vestibular damage are more complex and subtle. Very recently, reports have emerged that sub-threshold, noisy galvanic vestibular stimulation can enhance memory in humans, although this has not been investigated for spatial memory as yet. These studies add to the increasing evidence that suggests a connection between vestibular sensory information and memory in humans.

  5. Vestibular tributaries to the vein of the vestibular aqueduct

    Hansen, Jesper Marsner; Qvortrup, Klaus; Friis, Morten

    2010-01-01

    CONCLUSION: The vein of the vestibular aqueduct drains blood from areas extensively lined by vestibular dark cells (VDCs). A possible involvement in the pathogenesis of an impaired endolymphatic homeostasis can be envisioned at the level of the dark cells area. OBJECTIVES: The aim of this study...... was to investigate the vascular relationship between the vein of the vestibular aqueduct and the vestibular apparatus, with focus on the VDCs. METHODS: Sixteen male Wistar rats were divided into groups of 6 and 10. In the first group, 2 µm thick sections including the vein of the vestibular aqueduct, utricle...... relation to the VDCs in the utricle and the crista ampullaris of the lateral semicircular canal in the vestibular apparatus. One major vein emanated from these networks, which emptied into the vein of the vestibular aqueduct. Veins draining the saccule and the common crus of the superior and posterior...

  6. Computational Approaches to Vestibular Research

    Ross, Muriel D.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    The Biocomputation Center at NASA Ames Research Center is dedicated to a union between computational, experimental and theoretical approaches to the study of neuroscience and of life sciences in general. The current emphasis is on computer reconstruction and visualization of vestibular macular architecture in three-dimensions (3-D), and on mathematical modeling and computer simulation of neural activity in the functioning system. Our methods are being used to interpret the influence of spaceflight on mammalian vestibular maculas in a model system, that of the adult Sprague-Dawley rat. More than twenty 3-D reconstructions of type I and type II hair cells and their afferents have been completed by digitization of contours traced from serial sections photographed in a transmission electron microscope. This labor-intensive method has now been replace d by a semiautomated method developed in the Biocomputation Center in which conventional photography is eliminated. All viewing, storage and manipulation of original data is done using Silicon Graphics workstations. Recent improvements to the software include a new mesh generation method for connecting contours. This method will permit the investigator to describe any surface, regardless of complexity, including highly branched structures such as are routinely found in neurons. This same mesh can be used for 3-D, finite volume simulation of synapse activation and voltage spread on neuronal surfaces visualized via the reconstruction process. These simulations help the investigator interpret the relationship between neuroarchitecture and physiology, and are of assistance in determining which experiments will best test theoretical interpretations. Data are also used to develop abstract, 3-D models that dynamically display neuronal activity ongoing in the system. Finally, the same data can be used to visualize the neural tissue in a virtual environment. Our exhibit will depict capabilities of our computational approaches and

  7. Computational Approaches to Vestibular Research

    Ross, Muriel D.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    The Biocomputation Center at NASA Ames Research Center is dedicated to a union between computational, experimental and theoretical approaches to the study of neuroscience and of life sciences in general. The current emphasis is on computer reconstruction and visualization of vestibular macular architecture in three-dimensions (3-D), and on mathematical modeling and computer simulation of neural activity in the functioning system. Our methods are being used to interpret the influence of spaceflight on mammalian vestibular maculas in a model system, that of the adult Sprague-Dawley rat. More than twenty 3-D reconstructions of type I and type II hair cells and their afferents have been completed by digitization of contours traced from serial sections photographed in a transmission electron microscope. This labor-intensive method has now been replace d by a semiautomated method developed in the Biocomputation Center in which conventional photography is eliminated. All viewing, storage and manipulation of original data is done using Silicon Graphics workstations. Recent improvements to the software include a new mesh generation method for connecting contours. This method will permit the investigator to describe any surface, regardless of complexity, including highly branched structures such as are routinely found in neurons. This same mesh can be used for 3-D, finite volume simulation of synapse activation and voltage spread on neuronal surfaces visualized via the reconstruction process. These simulations help the investigator interpret the relationship between neuroarchitecture and physiology, and are of assistance in determining which experiments will best test theoretical interpretations. Data are also used to develop abstract, 3-D models that dynamically display neuronal activity ongoing in the system. Finally, the same data can be used to visualize the neural tissue in a virtual environment. Our exhibit will depict capabilities of our computational approaches and

  8. Computational Approaches to Vestibular Research

    Ross, Muriel D.; Wade, Charles E. (Technical Monitor)

    1994-01-01

    The Biocomputation Center at NASA Ames Research Center is dedicated to a union between computational, experimental and theoretical approaches to the study of neuroscience and of life sciences in general. The current emphasis is on computer reconstruction and visualization of vestibular macular architecture in three-dimensions (3-D), and on mathematical modeling and computer simulation of neural activity in the functioning system. Our methods are being used to interpret the influence of spaceflight on mammalian vestibular maculas in a model system, that of the adult Sprague-Dawley rat. More than twenty 3-D reconstructions of type I and type II hair cells and their afferents have been completed by digitization of contours traced from serial sections photographed in a transmission electron microscope. This labor-intensive method has now been replace d by a semiautomated method developed in the Biocomputation Center in which conventional photography is eliminated. All viewing, storage and manipulation of original data is done using Silicon Graphics workstations. Recent improvements to the software include a new mesh generation method for connecting contours. This method will permit the investigator to describe any surface, regardless of complexity, including highly branched structures such as are routinely found in neurons. This same mesh can be used for 3-D, finite volume simulation of synapse activation and voltage spread on neuronal surfaces visualized via the reconstruction process. These simulations help the investigator interpret the relationship between neuroarchitecture and physiology, and are of assistance in determining which experiments will best test theoretical interpretations. Data are also used to develop abstract, 3-D models that dynamically display neuronal activity ongoing in the system. Finally, the same data can be used to visualize the neural tissue in a virtual environment. Our exhibit will depict capabilities of our computational approaches and

  9. Medication (for Vestibular Disorders)

    ... Desorden Vestibular/Vértigo - En Español הפרעות וסטיבולריות Paid Advertisement Disclaimer Information on this website is not intended ... vertigo the patient will have a sensation of false or distorted self-motion. Are the patient’s symptoms ...

  10. Modulation of Memory by Vestibular Lesions and Galvanic Vestibular Stimulation

    PaulSmith

    2010-01-01

    For decades it has been speculated that there is a close association between the vestibular system and spatial memories constructed by areas of the brain such as the hippocampus. While many animal studies have been conducted which support this relationship, only in the last 10 years have detailed quantitative studies been carried out in patients with vestibular disorders. The majority of these studies suggest that complete bilateral vestibular loss results in spatial memory deficits that are ...

  11. Enlarged Vestibular Aqueducts and Childhood Hearing Loss

    ... Health Info » Hearing, Ear Infections, and Deafness Enlarged Vestibular Aqueducts and Childhood Hearing Loss On this page: ... more information about enlarged vestibular aqueducts? What are vestibular aqueducts? The inner ear Credit: NIH Medical Arts ...

  12. Spatial Cognition, Body Representation and Affective Processes: The Role of Vestibular Information beyond Ocular Reflexes and Control of Posture

    Fred W Mast

    2014-05-01

    Full Text Available A growing number of studies in humans demonstrate the involvement of vestibular information in tasks that are seemingly remote from well-known functions such as space constancy or postural control. In this review article we point out three emerging streams of research highlighting the importance of vestibular input: 1 Spatial Cognition: Modulation of vestibular signals can induce specific changes in spatial cognitive tasks like mental imagery and the processing of numbers. This has been shown in studies manipulating body orientation (changing the input from the otoliths, body rotation (changing the input from the semicircular canals, in clinical findings with vestibular patients, and in studies carried out in microgravity. There is also an effect in the reverse direction; top-down processes can affect perception of vestibular stimuli. 2 Body Representation: Numerous studies demonstrate that vestibular stimulation changes the representation of body parts, and sensitivity to tactile input or pain. Thus, the vestibular system plays an integral role in multisensory coordination of body representation. 3 Affective Processes and Disorders: Studies in psychiatric patients and patients with a vestibular disorder report a high comorbidity of vestibular dysfunctions and psychiatric symptoms. Recent studies investigated the beneficial effect of vestibular stimulation on psychiatric disorders, and how vestibular input can change mood and affect. These three emerging streams of research in vestibular science are – at least in part – associated with different neuronal core mechanisms. Spatial transformations draw on parietal areas, body representation is associated with somatosensory areas, and affective processes involve insular and cingulate cortices, all of which receive vestibular input. Even though a wide range of different vestibular cortical projection areas has been ascertained, their functionality still is scarcely understood.

  13. Audiologic diagnostics of vestibular schwannoma

    Komazec Zoran

    2004-01-01

    Full Text Available Introduction Vestibular schwannoma (acoustic neuroma is a rare, but important cause of sensorineural hearing loss. Patients with asymmetric hearing loss, or unilateral tinnitus should be evaluated expeditiously, to prevent further neurological damage. Audiologic diagnostics Audiologic diagnostics represents the basic diagnosis for early detection of vestibular schwannoma. Patients with vestibular schwannomas may present with a variety of clinical features, including retrocochlear pattern of sensorineural hearing loss. Supraliminary audiometry, tympano- metry, stapedius reflex and otoacoustic emissions as well as vestibular response to caloric testing are methods for selection of patients with suspicion of this tumor. Conclusion The golden standard for audiologic diagnostics of vestibular schwannoma is BAEP (Brainstem Auditory Evoked Potentials. Patients with pathological findings of BAEP should undergo MRI of the posterior fossa. Gadolinium-enhanced magnetic resonance imaging is the best and final tool for making a diagnosis of vestibular schwannoma.

  14. Perspectival Structure and Vestibular Processing

    Alsmith, Adrian John Tetteh

    2015-01-01

    I begin by contrasting a taxonomic approach to the vestibular system with the structural approach I take in the bulk of this commentary. I provide an analysis of perspectival structure. Employing that analysis and following the structural approach, I propose three lines of empirical investigation...... to selectively manipulate and measure vestibular processing and perspectival structure. The hope is that this serves to indicate how interdisciplinary research on vestibular processing might advance our understanding of the structural features of conscious experience....

  15. Vestibular compensation and vestibular rehabilitation. Current concepts and new trends.

    Deveze, A; Bernard-Demanze, L; Xavier, F; Lavieille, J-P; Elziere, M

    2014-01-01

    The aim of this review is to present the current knowledge of the mechanisms underlying the vestibular compensation and demonstrating how the vestibular rehabilitation is conducted to help the recovery of balance function. Vestibular rehabilitation is based on improving the natural phenomenon called vestibular compensation that occurs after acute vestibular disturbance or chronic and gradual misbalance. Central compensation implies three main mechanisms namely adaptation, substitution and habituation. The compensation, aided by the rehabilitation aimed to compensate and/or to correct the underused or misused of the visual, proprioceptive and vestibular inputs involved in the postural control. As the strategy of equilibration is not corrected, the patient is incompletely cured and remains with inappropriate balance control with its significance on the risk of fall and impact on quality of life. The vestibular rehabilitation helps to correct inappropriate strategy of equilibrium or to accelerate a good but slow compensation phenomenon. Nowadays, new tools are more and more employed for the diagnosis of vestibular deficit (that may include various sources of impairment), the assessment of postural deficit, the control of the appropriate strategy as well to facilitate the efficiency of the rehabilitation especially in elderly people. PMID:24502905

  16. Development and organization of polarity-specific segregation of primary vestibular afferent fibers in mice

    Maklad, Adel; Kamel, Suzan; Wong, Elaine; Fritzsch, Bernd

    2010-01-01

    A striking feature of vestibular hair cells is the polarized arrangement of their stereocilia as the basis for their directional sensitivity. In mammals, each of the vestibular end organs is characterized by a distinct distribution of these polarized cells. We utilized the technique of post-fixation transganglionic neuronal tracing with fluorescent lipid soluble dyes in embryonic and postnatal mice to investigate whether these polarity characteristics correlate with the pattern of connections...

  17. Childhood Vestibular Disorders: A Tutorial

    Mehta, Zarin; Stakiw, Daria B.

    2004-01-01

    There is a growing body of evidence that childhood disorders affecting the vestibular system, although rare, do exist. Describing symptoms associated with the vestibular mechanism for children may be difficult, resulting in misdiagnosing or under-diagnosing these conditions. The pathophysiology, symptoms, and management options of the more common…

  18. The vestibular implant: Quo vadis?

    Raymond eVan De Berg

    2011-08-01

    Full Text Available AbstractObjective: to assess the progress of the development of the vestibular implant and its feasibility short-term. Data sources: a search was performed in Pubmed, Medline and Embase. Key words used were vestibular prosth* and vestibular implant. The only search limit was language: English or Dutch. Additional sources were medical books, conference lectures and our personal experience with per-operative vestibular stimulation in patients selected for cochlear implantation.Study selection: all studies about the vestibular implant and related topics were included and evaluated by two reviewers. No study was excluded since every study investigated different aspects of the vestibular implant. Data extraction and synthesis: data was extracted by the first author from selected reports, supplemented by additional information, medical books conference lectures. Since each study had its own point of interest with its own outcomes, it was not possible to compare data of different studies. Conclusion: to use a basic vestibular implant in humans seems feasible in the very near future. Investigations show that electric stimulation of the canal nerves induces a nystagmus which corresponds to the plane of the canal which is innervated by the stimulated nerve branch. The brain is able to adapt to a higher baseline stimulation, while still reacting on a dynamic component. The best response will be achieved by a combination of the optimal stimulus (stimulus profile, stimulus location, precompensation, complemented by central vestibular adaptation. The degree of response will probably vary between individuals, depending on pathology and their ability to adapt.

  19. True incidence of vestibular schwannoma?

    Stangerup, Sven-Eric; Tos, Mirko; Thomsen, Jens;

    2010-01-01

    The incidence of diagnosed sporadic unilateral vestibular schwannomas (VS) has increased, due primarily to more widespread access to magnetic resonance imaging.......The incidence of diagnosed sporadic unilateral vestibular schwannomas (VS) has increased, due primarily to more widespread access to magnetic resonance imaging....

  20. Hypervascular vestibular Schwannoma: A case report

    Most vestibular schwannoma is hypovascular with well known poor tumor staining in cerebral angiography. However, hypervascular vestibular schwannoma might be observed as a rare subtype with increased risk of bleeding during surgery. Multimodal imaging features which represent hypervascularity of the tumor can be observed in hypervascular vestibular schwannoma. Here we report a case of hypervascular vestibular schwannoma with brief literature review.

  1. Hypervascular vestibular Schwannoma: A case report

    Kim, Ja Young; Yu, In Kyu [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of)

    2014-11-15

    Most vestibular schwannoma is hypovascular with well known poor tumor staining in cerebral angiography. However, hypervascular vestibular schwannoma might be observed as a rare subtype with increased risk of bleeding during surgery. Multimodal imaging features which represent hypervascularity of the tumor can be observed in hypervascular vestibular schwannoma. Here we report a case of hypervascular vestibular schwannoma with brief literature review.

  2. Vestibular disease in dogs and cats.

    Rossmeisl, John H

    2010-01-01

    The vestibular system is the major sensory (special proprioceptive) system that, along with the general proprioceptive and visual systems, maintains balance. Clinical signs of vestibular disease include asymmetric ataxia, head tilt, and pathologic nystagmus. Neuroanatomic localization of observed vestibular signs to either the peripheral or central components of the vestibular system is paramount to the management of the patient with vestibular dysfunction, as the etiology, diagnostic approaches, and prognoses are dependent on the neuroanatomic diagnosis. This article reviews functional vestibular neuroanatomy as well as the diagnosis and treatment of common causes of small animal vestibular disease. PMID:19942058

  3. Vestibular Rehabilitation Outcomes in the Elderly with Chronic Vestibular Dysfunction

    Bayat, Arash; Pourbakht, Akram; Saki, Nader; Zainun, Zuraida; Nikakhlagh, Soheila; Mirmomeni, Golshan

    2012-01-01

    Background Chronic vestibular dysfunction is a frustrating problem in the elderly and can have a tremendous impact on their life, but only a few studies are available. Vestibular rehabilitation therapy (VRT) is an important therapeutic option for the neuro-otologist in treating patients with significant balance deficits. Objectives The purpose of this study was to assess the effect of vestibular rehabilitation on dizziness in elderly patients with chronic vestibular dysfunction. Materials and Methods A total of 33 patients older than 60 years with chronic vestibular dysfunction were studied. Clinical and objective vestibular tests including videonystagmography (VNG) and dizziness handicap inventory (DHI) were carried out at their first visit, 2 weeks, and 8 weeks post-VRT. The VRT exercises were performed according to Cawthorne and Cooksey protocols. Results Oculomotor assessments were within normal limits in all patients. Nineteen patients (57.57%) showed abnormal canal paralysis on caloric testing which at follow-up sessions; CP values were decreased remarkably after VRT exercises. We found a significant improvement between pre-VRT and post-VRT total DHI scores (P < 0.001). This improvement was most prominent in functional subscore. Conclusions Our study demonstrated that VRT is an effective therapeutic method for elderly patients with chronic vestibular dysfunction. PMID:23396380

  4. Input/output properties of the lateral vestibular nucleus

    Boyle, R.; Bush, G.; Ehsanian, R.

    2004-01-01

    This article is a review of work in three species, squirrel monkey, cat, and rat studying the inputs and outputs from the lateral vestibular nucleus (LVN). Different electrophysiological shock paradigms were used to determine the synaptic inputs derived from thick to thin diameter vestibular nerve afferents. Angular and linear mechanical stimulations were used to activate and study the combined and individual contribution of inner ear organs and neck afferents. The spatio-temporal properties of LVN neurons in the decerebrated rat were studied in response to dynamic acceleration inputs using sinusoidal linear translation in the horizontal head plane. Outputs were evaluated using antidromic identification techniques and identified LVN neurons were intracellularly injected with biocytin and their morphology studied.

  5. Presbivértigo: ejercicios vestibulares Presbivertigo: vestibular exercises

    Esther Bernal Valls; Víctor Faus Cuñat; Raquel Bernal Valls

    2006-01-01

    El uso de ejercicios en el tratamiento de pacientes con déficit vestibular crónico está incrementándose de forma notable, lo que evidencia que se trata de un procedimiento que resulta beneficioso para este tipo de pacientes. Los buenos resultados que se obtienen sugieren que los ejercicios vestibulares dan lugar a una estabilidad postural y a una disminución de la sensación de desequilibrio.The use of exercises in the treatment of patients with vestibular deficits is increasing in a represent...

  6. Effects of caloric vestibular stimulation on serotoninergic system in the media vestibular nuclei of guinea pigs

    MA Fu-rong; LIU Jun-xiu; LI Xue-pei; MAO Jian-jun; ZHANG Qun-dan; JIA Hong-bo; MAO Lan-quan; ZHAO Rui

    2007-01-01

    Background Anatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation.Methods We used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n=6), ice water (n=6) and 37℃ water (n=4), and the groups of irrigation of the auricle with hot water (n=4) and ice water (n=4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation. Results In the caloric test the hot water (44℃) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37℃ water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water

  7. Presbivértigo: ejercicios vestibulares Presbivertigo: vestibular exercises

    Esther Bernal Valls

    2006-12-01

    Full Text Available El uso de ejercicios en el tratamiento de pacientes con déficit vestibular crónico está incrementándose de forma notable, lo que evidencia que se trata de un procedimiento que resulta beneficioso para este tipo de pacientes. Los buenos resultados que se obtienen sugieren que los ejercicios vestibulares dan lugar a una estabilidad postural y a una disminución de la sensación de desequilibrio.The use of exercises in the treatment of patients with vestibular deficits is increasing in a representative way, what evidences this is a profitable process for this kind of patients. The good results suggest that vestibular exercises permit a postural stability and a decrease in the perception of disequilibrium.

  8. Vestibular rehabilitation with visual stimuli in peripheral vestibular disorders

    Andréa Manso

    2016-04-01

    Full Text Available ABSTRACT INTRODUCTION: Visual stimuli can induce vestibular adaptation and recovery of body balance. OBJECTIVE: To verify the effect of visual stimuli by digital images on vestibular and body balance rehabilitation of peripheral vestibular disorders. METHODS: Clinical, randomized, prospective study. Forty patients aged between 23 and 63 years with chronic peripheral vestibular disorders underwent 12 sessions of rehabilitation with visual stimuli using digital video disk (DVD (experimental group or Cawthorne-Cooksey exercises (control group. The Dizziness Handicap Inventory (DHI, dizziness analog scale, and the sensitized Romberg static balance and one-leg stance tests were applied before and after the intervention. RESULTS: Before and after the intervention, there was no difference between the experimental and control groups (p > 0.005 regarding the findings of DHI, dizziness analog scale, and static balance tests. After the intervention, the experimental and control groups showed lower values (p < 0.05 in the DHI and the dizziness analog scale, and higher values (p < 0.05 in the static balance tests in some of the assessed conditions. CONCLUSION: The inclusion of visual stimuli by digital images on vestibular and body balance rehabilitation is effective in reducing dizziness and improving quality of life and postural control in individuals with peripheral vestibular disorders.

  9. Vestibular reflexes of otolith origin

    Wilson, Victor J.

    1988-01-01

    The vestibular system and its role in the maintenance of posture and in motion sickness is investigated using cats as experimental subjects. The assumption is that better understanding of the physiology of vestibular pathways is not only of intrinsic value, but will help to explain and eventually alleviate the disturbances caused by vestibular malfunction, or by exposure to an unusual environment such as space. The first project deals with the influence on the spinal cord of stimulation of the vestibular labyrinth, particularly the otoliths. A second was concerned with the properties and neural basis of the tonic neck reflex. These two projects are related, because vestibulospinal and tonic neck reflexes interact in the maintenance of normal posture. The third project began with an interest in mechanisms of motion sickness, and eventually shifted to a study of central control of respiratory muscles involved in vomiting.

  10. Enlarged Vestibular Aqueduct Syndrome (EVAS)

    ... referred to as EVA syndrome (EVA). CAUSES During fetal development, the vestibular aqueduct starts out as a wide ... in early gestation, or EVA results from aberrant development later in fetal and postnatal life. It is believed that an ...

  11. Stereotactic radiotherapy for vestibular schwannoma

    Muzevic, Dario; Legcevic, Jelena; Splavski, Bruno;

    2014-01-01

    BACKGROUND: Vestibular schwannomas (acoustic neuromas) are common benign tumours that arise from the Schwann cells of the vestibular nerve. Management options include observation with neuroradiological follow-up, microsurgical resection and stereotactic radiotherapy. OBJECTIVES: To assess...... the effect of stereotactic radiotherapy compared to observation, microsurgical resection, any other treatment modality, or a combination of two or more of the above approaches for vestibular schwannoma. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials; PubMed; EMBASE; CINAHL...... resection or any other possible treatment or combination of treatments in patients with a cerebellopontine angle tumour up to 3 cm in diameter, presumed to be a vestibular schwannoma. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by The Cochrane Collaboration. MAIN...

  12. Vestibular pathways involved in cognition

    Martin Hitier

    2014-07-01

    Full Text Available Recent discoveries have emphasized the role of the vestibular system in cognitive processes such as memory, spatial navigation and bodily self-consciousness. A precise understanding of the vestibular pathways involved is essential to understand the consequences of vestibular diseases for cognition, as well as develop therapeutic strategies to facilitate recovery. The knowledge of the “vestibular cortical projections areas”, defined as the cortical areas activated by vestibular stimulation, has dramatically increased over the last several years from both anatomical and functional points of view. Four major pathways have been hypothesized to transmit vestibular information to the vestibular cortex: 1 the vestibulo-thalamo-cortical pathway, which probably transmits spatial information about the environment via the parietal, entorhinal and perirhinal cortices to the hippocampus and is associated with spatial representation and self-versus object motion distinctions; 2 the pathway from the dorsal tegmental nucleus via the lateral mammillary nucleus, the anterodorsal nucleus of the thalamus to the entorhinal cortex, which transmits information for estimations of the head direction; 3 the pathway via the nucleus reticularis pontis oralis, the supramammillary nucleus and the medial septum to the hippocampus, which transmits information supporting hippocampal theta rhythm and memory; and 4 a possible pathway via the cerebellum, and the ventral lateral nucleus of the thalamus (perhaps to the parietal cortex, which transmits information for spatial learning. Finally a new pathway is hypothesized via the basal ganglia, potentially involved in spatial learning and spatial memory. From these pathways, progressively emerges the anatomical network of vestibular cognition.

  13. Atypical Manifestation of Vestibular Schwannoma

    Webster, Guilherme

    2013-09-01

    Full Text Available Introduction: Vestibular schwannoma (also known as acoustic neuroma is a benign tumor whose cells are derived from Schwann sheaths, which commonly occurs from the vestibular portion of the eighth cranial nerve. Furthermore, vestibular schwannomas account for ∼8% of intracranial tumors in adults and 80 to 90% of tumors of the cerebellopontine angle. Its symptoms are varied, but what stands out most is a unilateral sensorineural hearing loss, with a low index of speech recognition. Objective: Describe an atypical manifestation of vestibular schwannoma. Case Report: The 46-year-old woman had vertigo and binaural hearing loss and fullness, with ear, nose, and throat examination suggestive of cochlear injury. After 6 months, the patient developed worsening of symptoms and onset of right unilateral tinnitus. In further exams the signs of cochlear damage remained, except for the vestibular test (hyporeflexia. Magnetic resonance imaging showed an expansive lesion in the right cerebellopontine angle. Discussion: This report warns about the atypical manifestations of vestibular schwannoma, which must always be remembered in investigating and diagnosing hearing loss.

  14. Processing of vestibular inputs by the medullary lateral tegmental field of conscious cats: implications for generation of motion sickness

    McCall, Andrew A.; Moy, Jennifer D.; DeMayo, William M.; Puterbaugh, Sonya R.; Miller, Daniel J.; Catanzaro, Michael F.

    2013-01-01

    The dorsolateral reticular formation of the caudal medulla, the lateral tegmental field (LTF), participates in generating vomiting. LTF neurons exhibited complex responses to vestibular stimulation in decerebrate cats, indicating that they received converging inputs from a variety of labyrinthine receptors. Such a convergence pattern of vestibular inputs is appropriate for a brain region that participates in generating motion sickness. Since responses of brainstem neurons to vestibular stimulation can differ between decerebrate and conscious animals, the current study examined the effects of whole-body rotations in vertical planes on the activity of LTF neurons in conscious felines. Wobble stimuli, fixed-amplitude tilts, the direction of which moves around the animal at a constant speed, were used to determine the response vector orientation, and also to ascertain whether neurons had spatial–temporal convergence (STC) behavior (which is due to the convergence of vestibular inputs with different spatial and temporal properties). The proportion of LTF neurons with STC behavior in conscious animals (25 %) was similar to that in decerebrate cats. Far fewer neurons in other regions of the feline brainstem had STC behavior, confirming findings that many LTF neurons receive converging inputs from a variety of labyrinthine receptors. However, responses to vertical plane vestibular stimulation were considerably different in decerebrate and conscious felines for LTF neurons lacking STC behavior. In decerebrate cats, most LTF neurons had graviceptive responses to rotations, similar to those of otolith organ afferents. However, in conscious animals, the response properties were similar to those of semicircular canal afferents. These differences show that higher centers of the brain that are removed during decerebration regulate the labyrinthine inputs relayed to the LTF, either by gating connections in the brainstem or by conveying vestibular inputs directly to the region

  15. Differential diagnosis and treatment of vestibular vertigo

    Vladimir Anatolyevich Parfenov

    2010-06-01

    Full Text Available Vertigo is a common complaint that leads patients to visit physicians of various specialties. Diseases resulting in vestibular vertigo are very diverse and may be caused by lesion of both the central parts of the vestibular system and the peripheral vestibular apparatus. In many cases, its diagnosis can be made from complaints and a history of disease and special bedside tests requiring no sophisticated equipment. Management of vestibular vertigo should aim at treating the underlying disease; vestibular dilators as symptomatic therapy can be effective for several days. Vestibular exercises the efficiency of which can be enhanced by betahistine and other drugs accelerating vestibular compensation should be further needed. Data on the efficacy of betaver (betahistine in patients with vestibular vertigo are given.

  16. Galvanic stimulation of the vestibular periphery in guinea pigs during passive whole body rotation and self-generated head movement

    Shanidze, N.; Lim, K.; Dye, J.; King, W. M.

    2012-01-01

    Irregular vestibular afferents exhibit significant phase leads with respect to angular velocity of the head in space. This characteristic and their connectivity with vestibulospinal neurons suggest a functionally important role for these afferents in producing the vestibulo-collic reflex (VCR). A goal of these experiments was to test this hypothesis with the use of weak galvanic stimulation of the vestibular periphery (GVS) to selectively activate or suppress irregular afferents during passiv...

  17. Habituation of vestibular responses: An overview

    Collins, W. E.

    1973-01-01

    An historical survey of vestibular habituation experiments has been undertaken. Methodological problems are presented briefly, and the influence of arousal on vestibular responses is detailed. Data obtained from animals and from man are treated separately. At least for man, the term habituation may be better defined by a dynamic change in the form of vestibular responses than by a simple response reduction.

  18. Vestibular modulation of spatial perception.

    Ferrè, Elisa R; Longo, Matthew R; Fiori, Federico; Haggard, Patrick

    2013-01-01

    Vestibular inputs make a key contribution to the sense of one's own spatial location. While the effects of vestibular stimulation on visuo-spatial processing in neurological patients have been extensively described, the normal contribution of vestibular inputs to spatial perception remains unclear. To address this issue, we used a line bisection task to investigate the effects of galvanic vestibular stimulation (GVS) on spatial perception, and on the transition between near and far space. Brief left-anodal and right-cathodal GVS or right-anodal and left-cathodal GVS were delivered. A sham stimulation condition was also included. Participants bisected lines of different lengths at six distances from the body using a laser pointer. Consistent with previous results, our data showed an overall shift in the bisection bias from left to right as viewing distance increased. This pattern suggests leftward bias in near space, and rightward bias in far space. GVS induced strong polarity dependent effects in spatial perception, broadly consistent with those previously reported in patients: left-anodal and right-cathodal GVS induced a leftward bisection bias, while right-anodal and left-cathodal GVS reversed this effect, and produced bisection bias toward the right side of the space. Interestingly, the effects of GVS were comparable in near and far space. We speculate that vestibular-induced biases in space perception may optimize gathering of information from different parts of the environment. PMID:24133440

  19. Vestibular schwannoma surgery and headache.

    Levo, H; Blomstedt, G; Pyykkö, I

    2000-01-01

    The aim of the study was to evaluate aetiological factors for postoperative headache after vestibular schwannoma (VS) surgery with respect to asymmetric activation of vestibular reflexes. After surgery, 27 VS patients with persistent postoperative headache, 16 VS patients without headache and 9 healthy controls were examined. The vestibular, cervicocollic and cervicospinal reflexes were evaluated to study whether asymmetric activation of vestibular reflexes could cause headache. The effect of neck muscle and occipital nerve anaesthesia and the effect of sumatriptan on headache were also evaluated. The vestibular function of VS patients with headache did not differ from that of VS patients without headache, but was abnormal when compared to that of normal controls. The cervicospinal and cervicocollic reflexes did not differ in the patient groups. Injection of lidocaine around the operation scar gave pain relief to two patients, and one of them had occipital nerve entrapment. Infiltration of lidocaine deep in the neck muscles in the vicinity of the C2 root did not alleviate headache, but caused vertigo. Nine patients with musculogenic headache got pain relief from supportive neck collars, and two patients with cervicobrachial syndrome got pain relief from manual neck traction. The study shows that asymmetric activation of cervicocollic reflexes does not seem to be the reason for headache. Headache seems to be linked to neuropathic pain, allegedly caused by trigeminal irritation of the inner ear and the posterior fossa, which has recently been linked to vascular pain. PMID:10908966

  20. Vestibular modulation of spatial perception

    Elisa Raffaella Ferre

    2013-10-01

    Full Text Available Vestibular inputs make a key contribution to the sense of one’s own spatial location. While the effects of vestibular stimulation on visuo-spatial processing in neurological patients have been extensively described, the normal contribution of vestibular inputs to spatial perception remains unclear. To address this issue, we used a line bisection task to investigate the effects of galvanic vestibular stimulation (GVS on spatial perception, and on the transition between near and far space. Brief left-anodal and right-cathodal GVS or right-anodal and left-cathodal GVS were delivered. A sham stimulation condition was also included. Participants bisected lines of different lengths at six distances from the body using a laser pointer. Consistent with previous results, our data showed an overall shift in bisection bias from left to right as viewing distance increased. This pattern suggests leftward bias in near space, and rightward bias in far space. GVS induced strong polarity dependent effects in spatial perception, broadly consistent with those previously reported in patients: left-anodal and right-cathodal GVS induced a leftward bisection bias, while right-anodal and left-cathodal GVS reversed this effect, and produced bisection bias toward the right side of the space. Interestingly, the effects of GVS were comparable in near and far space. We speculate that vestibular-induced biases in space perception may optimize gathering of information from different parts of the environment.

  1. Antagonistic otolith-visual units in cat vestibular nuclei

    Daunton, Nancy G.; Christensen, Carol A.

    1992-01-01

    The nature of neural coding of visual (Vis) and vestibular (Vst) information on translational motion in the region of the vestibular nuclei was investigated using extracellular single-unit recordings in alert adult cats. Responses were recorded and averaged over 60 cycles of stimulation in the vertical and horizontal planes, which included the Vst (movement of the animal in the dark), Vis (movement within lighted visual surround), and combined Vis and Vst (movement of the animal within the lighted stationary visual surround). Data are reported on responses to stimulations along the axis showing maximal sensitivity. A small number of units were identified that showed an antagonistic relationship between their Vis and Vst responses (since they were maximally excited by Vis and by Vst stimulations in the same direction). Results suggest that antagonistic units may belong to an infrequently encountered, but functionally distinct, class of neurons.

  2. Development and organization of polarity-specific segregation of primary vestibular afferent fibers in mice.

    Maklad, Adel; Kamel, Suzan; Wong, Elaine; Fritzsch, Bernd

    2010-05-01

    A striking feature of vestibular hair cells is the polarized arrangement of their stereocilia as the basis for their directional sensitivity. In mammals, each of the vestibular end organs is characterized by a distinct distribution of these polarized cells. We utilized the technique of post-fixation transganglionic neuronal tracing with fluorescent lipid soluble dyes in embryonic and postnatal mice to investigate whether these polarity characteristics correlate with the pattern of connections between the endorgans and their central targets; the vestibular nuclei and cerebellum. We found that the cerebellar and brainstem projections develop independently from each other and have a non-overlapping distribution of neurons and afferents from E11.5 on. In addition, we show that the vestibular fibers projecting to the cerebellum originate preferentially from the lateral half of the utricular macula and the medial half of the saccular macula. In contrast, the brainstem vestibular afferents originate primarily from the medial half of the utricular macula and the lateral half of the saccular macula. This indicates that the line of hair cell polarity reversal within the striola region segregates almost mutually exclusive central projections. A possible interpretation of this feature is that this macular organization provides an inhibitory side-loop through the cerebellum to produce synergistic tuning effects in the vestibular nuclei. The canal cristae project to the brainstem vestibular nuclei and cerebellum, but the projection to the vestibulocerebellum originates preferentially from the superior half of each of the cristae. The reason for this pattern is not clear, but it may compensate for unequal activation of crista hair cells or may be an evolutionary atavism reflecting a different polarity organization in ancestral vertebrate ears. PMID:20424840

  3. Negative emotional stimuli enhance vestibular processing.

    Preuss, Nora; Ellis, Andrew W; Mast, Fred W

    2015-08-01

    Recent studies have shown that vestibular stimulation can influence affective processes. In the present study, we examined whether emotional information can also modulate vestibular perception. Participants performed a vestibular discrimination task on a motion platform while viewing emotional pictures. Six different picture categories were taken from the International Affective Picture System: mutilation, threat, snakes, neutral objects, sports, and erotic pictures. Using a Bayesian hierarchical approach, we were able to show that vestibular discrimination improved when participants viewed emotionally negative pictures (mutilation, threat, snake) when compared to neutral/positive objects. We conclude that some of the mechanisms involved in the processing of vestibular information are also sensitive to emotional content. Emotional information signals importance and mobilizes the body for action. In case of danger, a successful motor response requires precise vestibular processing. Therefore, negative emotional information improves processing of vestibular information. PMID:26098730

  4. Ion channels in mammalian vestibular afferents may set regularity of firing

    Eatock, Ruth Anne; Xue, Jingbing; Kalluri, Radha

    2008-01-01

    Rodent vestibular afferent neurons offer several advantages as a model system for investigating the significance and origins of regularity in neuronal firing interval. Their regularity has a bimodal distribution that defines regular and irregular afferent classes. Factors likely to be involved in setting firing regularity include the morphology and physiology of the afferents’ contacts with hair cells, which may influence the averaging of synaptic noise and the afferents’ intrinsic electrical...

  5. Pre-operative vestibular pattern and balance compensation after vestibular schwannoma surgery.

    Parietti-Winkler, C; Gauchard, G C; Simon, C; Perrin, P P

    2011-01-13

    This longitudinal study aimed to assess the sensorimotor balance strategies before and after vestibular schwannoma (VS) surgery according to the degree of pre-operative vestibular lesion. Thirty-eight VS patients were split in three groups according to caloric vestibular test results before surgery; nine had a symmetrical vestibular response (vestibular normoreflexy), 19 with a decreased response of more than 20% of the affected side (vestibular hyporeflexy) and 10 with an absent caloric response on the side of the affected labyrinth (vestibular areflexy). They underwent pendular rotary vestibular testing (RVT), allowing to evaluate gain and directional preponderance of the vestibulo-ocular reflex, and a sensory organisation test (SOT), evaluating balance control in six conditions (C1 to C6). These tests were performed shortly before, and 8 and 90 days after surgery. Directional preponderance performances of patients with vestibular normoreflexy or hyporeflexy followed a classical time-course with a huge asymmetry just after surgery and a recovery to pre-operative performances at 90 days; patients with vestibular areflexy were relatively stable in time. Variation in SOT performances of patients with vestibular normoreflexy, especially in the more complex C4 to C6, followed a classical time-course with an important postural degradation just after surgery and a recovery to pre-operative performances at 90 days. Patients with vestibular areflexy showed no balance degradation just after surgery and a marked increase in performances at 90 days after surgery, especially in C5 and C6. Performances of patients with vestibular hyporeflexy were intermediate, close to performances of patients with vestibular normoreflexy before surgery and close to performances of patients with vestibular areflexy at 8 and 90 days after surgery. Pre-operative vestibular function alteration triggers an adaptive process, characterized by a restoration of the symmetry of the vestibular nuclei

  6. Vestibular afferent responses to microrotational stimuli

    Myers, Steven F.; Lewis, Edwin R.

    1991-01-01

    Intracellular microelectrode recording/labeling techniques were used to investigate vestibular afferent responses in the bullfrog, to very small amplitude (less than 5 deg p-p) sinusoidal rotations in the vertical plane over the frequency range of 0.063-4 Hz. Robust responses to peak accelerations as low as 0.031 deg/sec per sec were obtained from units subsequently traced to either the central portion of the anterior canal crista or the striolar region of the utricle. All of these microrotationally sensitive afferent neurons had irregular resting discharge rates, and the majority had transfer ratios (relative to rotational velocity) of 1-40 spikes/sec per deg/sec. Individual utricular afferent velocity transfer ratios were nearly constant over the frequency range of 0.125-4 Hz. Canal units displayed decreasing response transfer ratios as stimulus frequencies increased. These findings indicate that, although utricular striolar and central crista afferent velocity transfer ratios to microrotations were very similar, utricular striolar afferent neurons were more faithful sensors of very small amplitude rotational velocity in the vertical plane.

  7. Distributive characteristics of projection from vestibular nuclei to nucleus raphe magnus in rats

    Jingyu Sun; Yulin Dong; Fuxing Zhang; Jianhua Qiu; Yunqing Li

    2007-01-01

    BACKGROUND: Morphological studies have confirmed that vestibular nuclei accepts serotoninergic projections from nucleus raphe magnus, nucleus raphes pallidus, etc. But it is still unclear whether there is bi-directional association between vestibular nuclei and nucleus raphe magnus.OBJECTIVE: To observe the characteristics of projective fibers from vestibular nuclei to nucleus raphe magnus using tetramethyl rhodamine (TMR) in rats, so as to provide more sufficient morphological evidence of neural association from vestibular nuclei. DESIGN: An observational experiment. SETTING: Department of Anatomy (K.K. Leung Brain Research Center), the Fourth Military Medical University of Chinese PLA. MATERIALS: Eighteen male SD rats of clean degree, weighing 250-280 g, were provided by the Experimental Animal Center of the Fourth Military Medical University of Chinese PLA. METHODS: The experiments were carried out in the laboratory of Department of Anatomy (K.K. Leung Brain Research Center), the Fourth Military Medical University of Chinese PLA from September 2006 to January 2007. All the rats were anesthetized with intraperitoneal injection of pentobarbital sodium, then according to the coordinates on the rat brain atlas, 0.1 μL TMR (100 g/L) was injected into nucleus raphes magnus via the tip of glass microtubule by means of microinjection. Seven days later, the rats were anesthetized, then perfused and fixed to remove brain, and then frozen coronal brain sections were prepared.The retrogradely labeled neurons in the injected and projected sites were observed under fluorescence microscope. Light filters with evoked wave length of 540-553 nm and emission wave length≥1 580 nm were selected to observe the orange TMR-labeled neurons. All the sections were observed and counted under the fluorescence microscope.MAIN OUTCOME MEASURES: Characteristics and number of retrogradely labeled neurons at different sites of nuclei. RESULTS: Totally 18 SD rats were enrolled, 9 of them were

  8. Age-Related Neurochemical Changes in the Vestibular Nuclei.

    Smith, Paul F

    2016-01-01

    There is evidence that the normal aging process is associated with impaired vestibulo-ocular reflexes (VOR) and vestibulo-spinal reflexes, causing reduced visual acuity and postural instability. Nonetheless, the available evidence is not entirely consistent, especially with respect to the VOR. Some recent studies have reported that VOR gain can be intact even above 80 years of age. Similarly, although there is evidence for age-related hair cell loss and neuronal loss in Scarpa's ganglion and the vestibular nucleus complex (VNC), it is not entirely consistent. Whatever structural and functional changes occur in the VNC as a result of aging, either to cause vestibular impairment or to compensate for it, neurochemical changes must underlie them. However, the neurochemical changes that occur in the VNC with aging are poorly understood because the available literature is very limited. This review summarizes and critically evaluates the available evidence relating to the noradrenaline, serotonin, dopamine, glutamate, GABA, glycine, and nitric oxide neurotransmitter systems in the aging VNC. It is concluded that, at present, it is difficult, if not impossible, to relate the neurochemical changes observed to the function of specific VNC neurons and whether the observed changes are the cause of a functional deficit in the VNC or an effect of it. A better understanding of the neurochemical changes that occur during aging may be important for the development of potential drug treatments for age-related vestibular disorders. However, this will require the use of more sophisticated methodology such as in vivo microdialysis with single neuron recording and perhaps new technologies such as optogenetics. PMID:26973593

  9. Effects of Visceral Inputs on the Processing of Labyrinthine Signals by the Inferior and Caudal Medial Vestibular Nuclei: Ramifications for the Production of Motion Sickness

    Arshian, Milad S.; Puterbaugh, Sonya R.; Miller, Daniel J.; Catanzaro, Michael F.; Hobson, Candace E.; McCall, Andrew A.; Yates, Bill J.

    2013-01-01

    Neurons located in the caudal aspect of the vestibular nucleus complex have been shown to receive visceral inputs, and project to brainstem regions that participate in generating emesis, such as nucleus tractus solitarius and the “vomiting region” in the lateral tegmental field (LTF). Consequently, it has been hypothesized that neurons in the caudal vestibular nuclei participate in triggering motion sickness, and that visceral inputs to the vestibular nucleus complex can affect motion sickness susceptibility. To obtain supporting evidence for this hypothesis, we determined the effects of intragastric infusion of copper sulfate (CuSO4) on responses of neurons in the inferior and caudal medial vestibular nuclei to rotations in vertical planes. CuSO4 readily elicits nausea and emesis by activating gastrointestinal afferents. Infusion of CuSO4 produced a >30% change in spontaneous firing rate of approximately one-third of neurons in the caudal aspect of the vestibular nucleus complex. These changes in firing rate developed over several minutes, presumably in tandem with the emetic response. The gains of responses to vertical vestibular stimulation of a larger fraction (approximately two-thirds) of caudal vestibular nucleus neurons were altered over 30% by administration of copper sulfate. The response gains of some units went up, and others went down, and there was no significant relationship with concurrent spontaneous firing rate change. These findings support the notion that the effects of visceral inputs on motion sickness susceptibility are mediated in part through the caudal vestibular nuclei. However, our previous studies showed that infusion of CuSO4 produced larger changes in responses to vestibular stimulation of LTF neurons, as well as parabrachial nucleus neurons that are believed to participate in generating nausea. Thus, integrative effects of gastrointestinal inputs on the processing of labyrinthine inputs must occur at brain sites that participate

  10. The vestibular control of balance after stroke

    Marsden, J. F.; Playford, E. D.; Day, B. L.

    2005-01-01

    Objectives: To examine vestibular control of balance in those who recovered the ability to stand after middle cerebral artery (MCA) stroke.Methods: Sixteen patients with MCA stroke were compared with 10 age matched controls. Two additional patients were studied with isolated corticospinal tract lesions, one each at the level of the pons and medulla. Vestibular evoked postural responses were obtained using galvanic vestibular stimulation (GVS) while patients stood with their eyes closed and he...

  11. Complications of Microsurgery of Vestibular Schwannoma

    Jan Betka; Eduard Zvěřina; Zuzana Balogová; Oliver Profant; Jiří Skřivan; Josef Kraus; Jiří Lisý; Josef Syka; Martin Chovanec

    2014-01-01

    Background. The aim of this study was to analyze complications of vestibular schwannoma (VS) microsurgery. Material and Methods. A retrospective study was performed in 333 patients with unilateral vestibular schwannoma indicated for surgical treatment between January 1997 and December 2012. Postoperative complications were assessed immediately after VS surgery as well as during outpatient followup. Results. In all 333 patients microsurgical vestibular schwannoma (Koos grade 1: 12, grade 2: 34...

  12. Visual mental imagery during caloric vestibular stimulation

    Mast, Fred W.; Merfeld, Daniel M.; Kosslyn, Stephen M.

    2006-01-01

    We investigated high-resolution mental imagery and mental rotation, while the participants received caloric vestibular stimulation. High-resolution visual mental imagery tasks have been shown to activate early visual cortex, which is deactivated by vestibular input. Thus, we predicted that vestibular stimulation would disrupt high-resolution mental imagery; this prediction was confirmed. In addition, mental rotation tasks have been shown to activate posterior parietal cortex, which is also en...

  13. A vestibular phenotype for Waardenburg syndrome?

    Black, F. O.; Pesznecker, S. C.; Allen, K.; Gianna, C.

    2001-01-01

    OBJECTIVE: To investigate vestibular abnormalities in subjects with Waardenburg syndrome. STUDY DESIGN: Retrospective record review. SETTING: Tertiary referral neurotology clinic. SUBJECTS: Twenty-two adult white subjects with clinical diagnosis of Waardenburg syndrome (10 type I and 12 type II). INTERVENTIONS: Evaluation for Waardenburg phenotype, history of vestibular and auditory symptoms, tests of vestibular and auditory function. MAIN OUTCOME MEASURES: Results of phenotyping, results of vestibular and auditory symptom review (history), results of vestibular and auditory function testing. RESULTS: Seventeen subjects were women, and 5 were men. Their ages ranged from 21 to 58 years (mean, 38 years). Sixteen of the 22 subjects sought treatment for vertigo, dizziness, or imbalance. For subjects with vestibular symptoms, the results of vestibuloocular tests (calorics, vestibular autorotation, and/or pseudorandom rotation) were abnormal in 77%, and the results of vestibulospinal function tests (computerized dynamic posturography, EquiTest) were abnormal in 57%, but there were no specific patterns of abnormality. Six had objective sensorineural hearing loss. Thirteen had an elevated summating/action potential (>0.40) on electrocochleography. All subjects except those with severe hearing loss (n = 3) had normal auditory brainstem response results. CONCLUSION: Patients with Waardenburg syndrome may experience primarily vestibular symptoms without hearing loss. Electrocochleography and vestibular function tests appear to be the most sensitive measures of otologic abnormalities in such patients.

  14. Vestibular Function Research aboard Spacelab

    Mah, R. W.; Daunton, N. G.

    1978-01-01

    NASA is planning to perform a series of Vestibular Function Research (VFR) investigations on the early STS missions to investigate those neurosensory and related physiological processes believed to be associated with the space flight nausea syndrome. The first flight is scheduled for the 1981 Spacelab III Mission in which four frog specimens, mounted on a frog tilting/centrifuge device, will be subjected to periodic acceleration stimuli and periods of artificial gravity. The vestibular nerve firing responses of each frog specimen will be monitored through implanted neutral bouyancy microelectrodes and transmitted to the ground for quick analysis during the flight. The experimentation will be directed at investigating: (1) adaptation to weightlessness; (2) response to acceleration stimuli; (3) response to artificial gravity (in a weightlessness environment) and (4) readaptation to earth's gravity upon return.

  15. Effects of Weightlessness on Vestibular Development: Summary of Research on NIH.R1

    Fritzsch, Bernd; Bruce, L. L.

    1998-01-01

    In our original application we proposed to investigate the effects of gravity on the formation of connections between the gravity receptors of the ear and the brain in rat pups raised in space beginning at an age before these connections are made until near the time of birth, when they are to some extent functional. We used the neuronal tracer, Dil, which could be applied to tissue obtained immediately after landing of the space shuttle, thus minimizing changes due to the earth's gravity. We hoped to determine whether the vestibular system develops in two phases, as do other sensory systems (such as the visual system). In these other systems the first phase of development is controlled genetically and the second phase is controlled by environmental stimulation. Our data collected strongly supports the idea that the vestibular system has these same two phases of development. The tissue obtained from the NIH.R1 experiment was of exceptionally high quality for our analysis. Therefore, we expanded our investigation into the ultrastructural effects of microgravity on vestibular development. For the sake of clarity we will subdivide our summary into two categories: (1) analysis of the branching pattern of axons between the vestibular nerve and the gravistatic receptors of the ear in flight and control animals, and (2) analysis of the branching pattern of axons between the vestibular nerve and the brain in flight and control animals.

  16. [Vestibular influences on human locomotion: results obtained using galvanic vestibular stimulation].

    Stolbkov, Iu K; Gerasimenko, Iu P

    2014-06-01

    Locomotion is the most important mode of our movement in space. The role of the vestibular system during human locomotion is not well studied, mainly due to problems associated with its isolation stimulation. It is difficult to stimulate this system in isolation during locomotion because the real movement of the head to activate the vestibular end-organs inevitably leads to the activation of other sensory inputs. Galvanic stimulation is not a natural way to stimulate the vestibular system, but it has the advantage providing an isolated stimulation of the vestibular inputs. This technique is relatively novel in the examination of vestibular contributions during human locomotion. In our review we consider the current data regarding the effect of vestibular signals on human locomotion by using galvanic vestibular stimulation. PMID:25665394

  17. Projection neurons of the vestibulo-sympathetic reflex pathway.

    Holstein, Gay R; Friedrich, Victor L; Martinelli, Giorgio P

    2014-06-15

    Changes in head position and posture are detected by the vestibular system and are normally followed by rapid modifications in blood pressure. These compensatory adjustments, which allow humans to stand up without fainting, are mediated by integration of vestibular system pathways with blood pressure control centers in the ventrolateral medulla. Orthostatic hypotension can reflect altered activity of this neural circuitry. Vestibular sensory input to the vestibulo-sympathetic pathway terminates on cells in the vestibular nuclear complex, which in turn project to brainstem sites involved in the regulation of cardiovascular activity, including the rostral and caudal ventrolateral medullary regions (RVLM and CVLM, respectively). In the present study, sinusoidal galvanic vestibular stimulation was used to activate this pathway, and activated neurons were identified through detection of c-Fos protein. The retrograde tracer Fluoro-Gold was injected into the RVLM or CVLM of these animals, and immunofluorescence studies of vestibular neurons were conducted to visualize c-Fos protein and Fluoro-Gold concomitantly. We observed activated projection neurons of the vestibulo-sympathetic reflex pathway in the caudal half of the spinal, medial, and parvocellular medial vestibular nuclei. Approximately two-thirds of the cells were ipsilateral to Fluoro-Gold injection sites in both the RVLM and CVLM, and the remainder were contralateral. As a group, cells projecting to the RVLM were located slightly rostral to those with terminals in the CVLM. Individual activated projection neurons were multipolar, globular, or fusiform in shape. This study provides the first direct demonstration of the central vestibular neurons that mediate the vestibulo-sympathetic reflex. PMID:24323841

  18. Swimming behaviour and calcium incorporation into inner ear otoliths of fish after vestibular nerve transection

    Edelmann, E.; Anken, R. H.; Rahmann, H.

    2004-01-01

    Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium tracer alizarin complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated. Like most neonate swordtails, Type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal, and the otolithic calcium incorporation in controls of the same batch was symmetric. In Type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetric. These results show that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. In conclusion, the regulation of otolithic calcium incorporation is guided neuronally, in part via the vestibular nerve and, in part, via a further pathway, which remains to be addressed in the course of future investigations.

  19. Epidemiology and natural history of vestibular schwannomas

    Stangerup, Sven-Eric; Caye-Thomasen, Per

    2012-01-01

    This article describes various epidemiologic trends for vestibular schwannomas over the last 35 years, including a brief note on terminology. Additionally, it provides information on the natural history of tumor growth and hearing level following the diagnosis of a vestibular schwannoma...

  20. Task, muscle and frequency dependent vestibular control of posture

    Forbes, P.A.; Siegmund, G.P.; Schouten, A.C.; Blouin, J.S.

    2015-01-01

    The vestibular system is crucial for postural control; however there are considerable differences in the task dependence and frequency response of vestibular reflexes in appendicular and axial muscles. For example, vestibular reflexes are only evoked in appendicular muscles when vestibular informati

  1. BRN 3.1 Knockouts Affect the Vestibular, Autonomic, and Circadian Rhythm Responses to 2G Exposure

    Murakami, D. M.; Erkman, L.; Rosenfeld, M. G.; Fuller, C. A.

    1999-01-01

    Our previous studies have demonstrated that 2G exposure via centrifugation significantly attenuated the daily mean and circadian rhythm amplitude of rat body temperature (Tb), heart rate, and activity (Act). In addition, 2G exposure activates neural responses in several vestibular, autonomic, and circadian nuclei. Although we have characterized the effect of 2G on an animal's physiological, neuronal, and behavioral responses, it will be important to understand the underlying neural and physiological mechanisms that mediate those responses. For example, the vestibular responses, proprioceptive feedback, or fluid shifts may be the critical factors that mediate the responses to 2G. As a first step to understand the relative importance of these different response pathways to altered gravitational fields, this study examined the contribution of the vestibular system by utilizing an animal model from molecular biology. Brain 3.1 (Bm 3.1) is a POU domain homeobox gene involved in the normal development of the vestibular and auditory system. Brn 3.1 deletion results in a loss of hair cells in the otoliths, semicircular canals, and cochlea. As a result mice with a Brn 3.1 deletion do not have a functioning vestibular or auditory system. The BRN 3.1 knockout mouse could be a very useful animal model for isolating the role of the vestibular system in mediating the physiological responses to 2G exposure. Therefore, this study compared the effect of 2G exposure via centrifugation between Brn 3.1 knockout (KO) versus Wildtype (W) mice.

  2. Effects of vibrotactile vestibular substitution on vestibular rehabilitation - preliminary study,

    Cibele Brugnera

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: Some patients with severe impairment of body balance do not obtain adequate improvement from vestibular rehabilitation (VR. OBJECTIVE: To evaluate the effectiveness of Vertiguard(tm biofeedback equipment as a sensory substitution (SS of the vestibular system in patients who did not obtain sufficient improvement from VR. METHODS: This was a randomized prospective clinical study. Thirteen patients without satisfactory response to conventional VR were randomized into a study group (SG, which received the vibrotactile stimulus from Vertiguard(tm for ten days, and a control group (CG, which used equipment without the stimulus. For pre- and post-treatment assessment, the Sensory Organization Test (SOT protocol of the Computerized Dynamic Posturography (CDP and two scales of balance self-perception, Activities-specific Balance Confidence (ABC and Dizziness Handicap Inventory (DHI, were used. RESULTS: After treatment, only the SG showed statistically significant improvement in C5 (p = 0.007 and C6 (p = 0.01. On the ABC scale, there was a significant difference in the SG (p= 0.04. The DHI showed a significant difference in CG and SG with regard to the physical aspect, and only in the SG for the functional aspect (p = 0.04. CONCLUSION: The present findings show that sensory substitution using the vibrotactile stimulus of the Vertiguard(tm system helped with the integration of neural networks involved in maintaining posture, improving the strategies used in the recovery of body balance.

  3. Effects of microgravity on vestibular development and function in rats: genetics and environment

    Ronca, A. E.; Fritzsch, B.; Alberts, J. R.; Bruce, L. L.

    2000-01-01

    Our anatomical and behavioral studies of embryonic rats that developed in microgravity suggest that the vestibular sensory system, like the visual system, has genetically mediated processes of development that establish crude connections between the periphery and the brain. Environmental stimuli also regulate connection formation including terminal branch formation and fine-tuning of synaptic contacts. Axons of vestibular sensory neurons from gravistatic as well as linear acceleration receptors reach their targets in both microgravity and normal gravity, suggesting that this is a genetically regulated component of development. However, microgravity exposure delays the development of terminal branches and synapses in gravistatic but not linear acceleration-sensitive neurons and also produces behavioral changes. These latter changes reflect environmentally controlled processes of development.

  4. Glutamate and GABA in Vestibulo-Sympathetic Pathway Neurons

    Holstein, Gay R.; Friedrich, Victor L. Jr.; Martinelli, Giorgio P.

    2016-01-01

    The vestibulo-sympathetic reflex (VSR) actively modulates blood pressure during changes in posture. This reflex allows humans to stand up and quadrupeds to rear or climb without a precipitous decline in cerebral perfusion. The VSR pathway conveys signals from the vestibular end organs to the caudal vestibular nuclei. These cells, in turn, project to pre-sympathetic neurons in the rostral and caudal ventrolateral medulla (RVLM and CVLM, respectively). The present study assessed glutamate- and ...

  5. Influence of cochlear implantation on vestibular function.

    Chen, Xiulan; Chen, Xiaohua; Zhang, Fan; Qin, Zhaobing

    2016-07-01

    Conclusion Vestibular function in patients can be damaged following cochlear implantation. Therefore, assessing the pre-operative vestibular status, carefully choosing the side of implantation, and preserving function by using minimally invasive surgical techniques are important. Objectives The aim of this study was to assess the influence of cochlear implantation on vestibular function in patients with severe and profound sensorineural hearing loss, and to analyze a possible correlation between the changes in vestibular testing and post-operative vestibular symptoms. Methods Thirty-four patients were evaluated for vestibular function using the cervical and ocular vestibular-evoked myogenic potentials (cVEMP and oVEMP, respectively), and 29 patients underwent caloric tests pre-operatively and 4 weeks post-operatively. Results Before surgery, the cVEMPs were recorded bilaterally in 22 patients, unilaterally in eight patients, and absent bilaterally in four patients. The oVEMPs were recorded bilaterally in 19 patients, unilaterally in six patients, and absent bilaterally in nine patients. After implantation, the cVEMPs were absent in 10 patients and the oVEMPs were absent in seven patients on the implanted side. Caloric tests demonstrated canal paresis in 17 patients, and normal responses were recorded in 12 of the 29 patients pre-operatively. There was a significant decrease post-implantation in the ear implanted, with the exception of two patients. Two patients presented with vertigo and another two patients reported slight unsteadiness post-operatively, but all symptoms resolved within 7 days. The impaired vestibular function did not correlate with vestibular symptoms, age, or gender. Function on the contralateral side remained unaffected. PMID:27008103

  6. Restoration of 3D Vestibular Sensation in Rhesus Monkeys Using a Multichannel Vestibular Prosthesis

    Dai, Chenkai; Fridman, Gene Y.; Davidovics, Natan; Chiang, Bryce; Ahn, Joong Ho; DELLA SANTINA, CHARLES C.

    2011-01-01

    Profound bilateral loss of vestibular hair cell function can cause chronically disabling loss of balance and inability to maintain stable vision during head and body movements. We have previously shown that chinchillas rendered bilaterally vestibular-deficient via intratympanic administration of the ototoxic antibiotic gentamicin regain a more nearly normal 3-dimensional vestibulo-ocular reflex (3D VOR) when head motion information sensed by a head-mounted multichannel vestibular prosthesis (...

  7. Progress toward development of a multichannel vestibular prosthesis for treatment of bilateral vestibular deficiency.

    Fridman, Gene Y; Della Santina, Charles C

    2012-11-01

    This article reviews vestibular pathology and the requirements and progress made in the design and construction of a vestibular prosthesis. Bilateral loss of vestibular sensation is disabling. When vestibular hair cells are injured by ototoxic medications or other insults to the labyrinth, the resulting loss of sensory input disrupts vestibulo-ocular reflexes (VORs) and vestibulo-spinal reflexes that normally stabilize the eyes and body. Affected individuals suffer poor vision during head movement, postural instability, chronic disequilibrium, and cognitive distraction. Although most individuals with residual sensation compensate for their loss over time, others fail to do so and have no adequate treatment options. A vestibular prosthesis analogous to cochlear implants but designed to modulate vestibular nerve activity during head movement should improve quality of life for these chronically dizzy individuals. We describe the impact of bilateral loss of vestibular sensation, animal studies supporting feasibility of prosthetic vestibular stimulation, the current status of multichannel vestibular sensory replacement prosthesis development, and challenges to successfully realizing this approach in clinical practice. In bilaterally vestibular-deficient rodents and rhesus monkeys, the Johns Hopkins multichannel vestibular prosthesis (MVP) partially restores the three-dimensional (3D) VOR for head rotations about any axis. Attempts at prosthetic vestibular stimulation of humans have not yet included the 3D eye movement assays necessary to accurately evaluate VOR alignment, but these initial forays have revealed responses that are otherwise comparable to observations in animals. Current efforts now focus on refining electrode design and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimizing stimulus protocols to improve dynamic range and reduce excitation-inhibition asymmetry, and adapting laboratory MVP prototypes into devices

  8. Migration of R28 Retinal Precursor Cells into Cochlear and Vestibular Organs

    DING Dalian; Gail Seigel; Richard Salvi

    2006-01-01

    Damaged hair cells and neurons in the inner ear generally can not be replaced in mammals. The loss of these cells causes permanent functional disorders in both the cochlear and vestibular systems. Transplantation of retinal precursor cells, R28 cells, into inner ear tissue may help replace missing cells. The aim of the current project was to induce R28 cell transdifferentiation into cochlear and vestibular cell types under culture conditions. The first part was related to R28 cell labeling with DiI fluorescence that would help identify and track R28 cells. The second part involved co-culturing R28 cells in cochlear and vestibular organotropic cultures or isolated spiral ganglion neurons. The results suggest that R28 cells have the potential to differentiate into supporting cell types and spiral ganglion neurons in serum free medium, probably under the influence of diffusible signals from inner ear tissues. This information is useful for future efforts in inducing stem cell differentiation in the inner ear to replace lost sensory and neural cells.

  9. Changes in Histamine Receptors (H1, H2, and H3 Expression in Rat Medial Vestibular Nucleus and Flocculus after Unilateral Labyrinthectomy: Histamine Receptors in Vestibular Compensation.

    Liuqing Zhou

    Full Text Available Vestibular compensation is the process of behavioral recovery following peripheral vestibular lesion. In clinics, the histaminergic medicine is the most widely prescribed for the treatment of vertigo and motion sickness, however, the molecular mechanisms by which histamine modulates vestibular function remain unclear. During recovery from the lesion, the modulation of histamine receptors in the medial vestibular nucleus (MVN and the flocculus may play an important role. Here with the means of quantitative real-time PCR, western blotting and immunohistochemistry, we studied the expression of histamine receptors (H1, H2, and H3 in the bilateral MVN and the flocculus of rats on the 1st, 3rd, and 7th day following unilateral labyrinthectomy (UL. Our results have shown that on the ipsi-lesional flocculus the H1, H2 and H3 receptors mRNA and the protein increased significantly on the 1st and 3rd day, with compare of sham controls and as well the contralateral side of UL. However, on the 7th day after UL, this expression returned to basal levels. Furthermore, elevated mRNA and protein levels of H1, H2 and H3 receptors were observed in the ipsi-lesional MVN on the 1st day after UL compared with sham controls and as well the contralateral side of UL. However, this asymmetric expression was absent by the 3rd post-UL. Our findings suggest that the upregulation of histamine receptors in the MVN and the flocculus may contribute to rebalancing the spontaneous discharge in bilateral MVN neurons during vestibular compensation.

  10. Sensory Dissociation in Vestibular Function Assessment

    Tolmachev Ivan

    2016-01-01

    Full Text Available The project aims to create а solution to the problem of early diagnostics of neurodegenerative disorders, accompanied by imbalance, and to develop rehabilitation methods for patients with vestibular disorders. The balanced upright position is a result of interaction between vestibular system, skeleton and muscles, visual, and proprioceptive systems. Postural abnormalities are caused by morphological or functional alteration of the components of the equilibrioception system. These disorders weaken the ability of the central nervous system to process vestibular, visual and proprioceptive signals, which are responsible for the sense of balance. Moreover, it also decreases the plasticity of the nervous system, resulting in adaptation disfunctionality. Unfortunately, premorbid detection of vestibular dysfunctions is quite a complicated test because available methods to evaluate postural reflexes have low sensitivity and specifity. Consequently, the development of methods to assess functional state of the equilibrioception system becoming viable in order to detect neurodegenerative disorders as early as possible, to control treatment and rehabilitation procedures.

  11. Outcome analysis of individualized vestibular rehabilitation protocols

    Black, F. O.; Angel, C. R.; Pesznecker, S. C.; Gianna, C.

    2000-01-01

    OBJECTIVE: To determine the outcome of vestibular rehabilitation protocols in subjects with peripheral vestibular disorders compared with normal and abnormal control subjects. STUDY DESIGN: Prospective study using repeated measure, matched control design. Subjects were solicited consecutively according to these criteria: vestibular disorder subjects who had abnormal results of computerized dynamic posturography (CDP) sensory organization tests (SOTs) 5 and 6 and underwent rehabilitation; vestibular disorder subjects who had abnormal results of SOTs 5 and 6 and did not undergo rehabilitation; and normal subjects (normal SOTs). SETTING: Tertiary neurotology clinic. SUBJECTS: Men and women over age 18 with chronic vestibular disorders and chief complaints of unsteadiness, imbalance, and/or motion intolerance, and normal subjects. INTERVENTIONS: Pre- and post-rehabilitation assessment included CDP, vestibular disability, and activities of daily living questionnaires. Individualized rehabilitation plans were designed and implemented to address the subject's specific complaints and functional deficits. Supervised sessions were held at weekly intervals, and self-administered programs were devised for daily home use. MAIN OUTCOME MEASURES: CDP composite and SOT scores, number of falls on CDP, and self-assessment questionnaire results. RESULTS: Subjects who underwent rehabilitation (Group A) showed statistically significant improvements in SOTs, overall composite score, and reduction in falls compared with abnormal (Group B) control groups. Group A's performances after rehabilitation were not significantly different from those of normal subjects (Group C) in SOTs 3 through 6, and close to normal on SOTs 1 and 2. Subjects in Group A also reported statistically significant symptomatic improvement. CONCLUSIONS: Outcome measures of vestibular protocol physical therapy confirmed objective and subjective improvement in subjects with chronic peripheral vestibular disorders. These

  12. Vestibular schwannoma: role of conservative management

    Suryanarayanan, R.; Ramsden, R. T.; Saeed, S R; Aggarwal, R.; King, A. T.; Rutherford, S A.; Evans, D G; Gillespie, J. E.

    2010-01-01

    Objective: To assess the outcome of conservative management of vestibular schwannoma.Study design: Observational study. Setting: Tertiary referral centre.Patients: Four hundred and thirty-six patients with vestibular schwannoma (490 tumours), including 327 sporadic tumours and 163 tumours in 109 patients with neurofibromatosis type two.Main outcome measures: The relationship of tumour growth to tumour size at presentation, and to certain demographic features.Results: The initial tumour size w...

  13. Sensory Dissociation in Vestibular Function Assessment

    Tolmachev Ivan; Brazovsky Konstantin; Schadenko Sergey; Korzhenkova Ekaterina

    2016-01-01

    The project aims to create а solution to the problem of early diagnostics of neurodegenerative disorders, accompanied by imbalance, and to develop rehabilitation methods for patients with vestibular disorders. The balanced upright position is a result of interaction between vestibular system, skeleton and muscles, visual, and proprioceptive systems. Postural abnormalities are caused by morphological or functional alteration of the components of the equilibrioception system. These disorders we...

  14. Current treatment options in vestibular migraine

    Mark Obermann

    2014-12-01

    Full Text Available Approximately 1% of the general population in western industrialized countries suffers from vestibular migraine. However, it remains widely unknown and often under diagnosed even despite the recently published diagnostic criteria for vestibular migraine. Treatment trials that specialize on vestibular migraine are scarce and systematic randomized controlled clinical trials are only now emerging.This review summarizes the knowledge on the currently available treatment options that were tested specifically for vestibular migraine and gives an evidence-based, informed treatment recommendation with all its limitations.To date only two randomized controlled treatment trials provide limited evidence for the use of rizatriptan and zolmitriptan for the treatment of vestibular migraine attacks because of methodological shortcommings. There is an on-going a multicenter randomized placebo-controlled trial testing metoprolol 95 mg vs. placebo (PROVEMIG-trial. Therefore, the therapeutic recommendations for the prophylactic treatment of vestibular migraine are currently widely based on the guidelines of migraine with and without aura as well as expert opinion.

  15. Interactive Healthcare Systems in the Home: Vestibular Rehabilitation

    Aarhus, Rikke; Grönvall, Erik; Larsen, Simon Bo

    2010-01-01

    Vestibular dysfunction is a balance disorder, causing dizziness that provokes discomfort and fall situations. This paper discusses early results from a project that aims to develop assistive technologies to support home-based rehabilitation for elderly affected by Vestibular dysfunction....

  16. PLCγ-activated signalling is essential for TrkB mediated sensory neuron structural plasticity

    Rocha-Sanchez Sonia M

    2010-10-01

    Full Text Available Abstract Background The vestibular system provides the primary input of our sense of balance and spatial orientation. Dysfunction of the vestibular system can severely affect a person's quality of life. Therefore, understanding the molecular basis of vestibular neuron survival, maintenance, and innervation of the target sensory epithelia is fundamental. Results Here we report that a point mutation at the phospholipase Cγ (PLCγ docking site in the mouse neurotrophin tyrosine kinase receptor TrkB (Ntrk2 specifically impairs fiber guidance inside the vestibular sensory epithelia, but has limited effects on the survival of vestibular sensory neurons and growth of afferent processes toward the sensory epithelia. We also show that expression of the TRPC3 cation calcium channel, whose activity is known to be required for nerve-growth cone guidance induced by brain-derived neurotrophic factor (BDNF, is altered in these animals. In addition, we find that absence of the PLCγ mediated TrkB signalling interferes with the transformation of bouton type afferent terminals of vestibular dendrites into calyces (the largest synaptic contact of dendrites known in the mammalian nervous system on type I vestibular hair cells; the latter are normally distributed in these mutants as revealed by an unaltered expression pattern of the potassium channel KCNQ4 in these cells. Conclusions These results demonstrate a crucial involvement of the TrkB/PLCγ-mediated intracellular signalling in structural aspects of sensory neuron plasticity.

  17. From ear to uncertainty: vestibular contributions to cognitive function

    Paul F. Smith; Zheng, Yiwen

    2013-01-01

    In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and neocortex play in spatial orientation. In this review we summarize the evidence that vestibular loss causes cognitive disorders, espe...

  18. From ear to uncertainty: Vestibular contributions to cognitive function.

    Paul Smith

    2013-01-01

    In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and cortex play in spatial orientation. In this review we summarise the evidence that vestibular loss causes cognitive disorders, especia...

  19. Tests of walking balance for screening vestibular disorders

    Cohen, Helen S.; Mulavara, Ajitkumar P.; Peters, Brian T.; Sangi-Haghpeykar, Haleh; Bloomberg, Jacob J.

    2012-01-01

    Few reliable tests are available for screening people rapidly for vestibular disorders although such tests would be useful for a variety of testing situations. Balance testing is widely performed but of unknown value for screening. The goal of this study was to determine the value of tests of walking balance for screening people with vestibular impairments. We tested three groups of patients with known vestibular impairments: benign paroxysmal positional vertigo, unilateral vestibular weaknes...

  20. Complications of Microsurgery of Vestibular Schwannoma

    Jan Betka

    2014-01-01

    Full Text Available Background. The aim of this study was to analyze complications of vestibular schwannoma (VS microsurgery. Material and Methods. A retrospective study was performed in 333 patients with unilateral vestibular schwannoma indicated for surgical treatment between January 1997 and December 2012. Postoperative complications were assessed immediately after VS surgery as well as during outpatient followup. Results. In all 333 patients microsurgical vestibular schwannoma (Koos grade 1: 12, grade 2: 34, grade 3: 62, and grade 4: 225 removal was performed. The main neurological complication was facial nerve dysfunction. The intermediate and poor function (HB III–VI was observed in 124 cases (45% immediately after surgery and in 104 cases (33% on the last followup. We encountered disordered vestibular compensation in 13%, permanent trigeminal nerve dysfunction in 1%, and transient lower cranial nerves (IX–XI deficit in 6%. Nonneurological complications included CSF leakage in 63% (lateral/medial variant: 99/1%, headache in 9%, and intracerebral hemorrhage in 5%. We did not encounter any case of meningitis. Conclusions. Our study demonstrates that despite the benefits of advanced high-tech equipment, refined microsurgical instruments, and highly developed neuroimaging technologies, there are still various and significant complications associated with vestibular schwannomas microsurgery.

  1. Sensorial countermeasures for vestibular spatial disorientation.

    Paillard, Aurore C; Quarck, Gaëlle; Denise, Pierre

    2014-05-01

    Spatial disorientation is defined as an erroneous body orientation perceived by pilots during flights. Limits of the vestibular system provoke frequent spatial disorientation mishaps. Although vestibular spatial disorientation is experienced frequently in aviation, there is no intuitive countermeasure against spatial disorientation mishaps to date. The aim of this review is to describe the current sensorial countermeasures and to examine future leads in sensorial ergonomics for vestibular spatial disorientation. This work reviews: 1) the visual ergonomics, 2) the vestibular countermeasures, 3) the auditory displays, 4) the somatosensory countermeasures, and, finally, 5) the multisensory displays. This review emphasizes the positive aspects of auditory and somatosensory countermeasures as well as multisensory devices. Even if some aspects such as sensory conflict and motion sickness need to be assessed, these countermeasures should be taken into consideration for ergonomics work in the future. However, a recent development in aviation might offer new and better perspectives: unmanned aerial vehicles. Unmanned aerial vehicles aim to go beyond the physiological boundaries of human sensorial systems and would allow for coping with spatial disorientation and motion sickness. Even if research is necessary to improve the interaction between machines and humans, this recent development might be incredibly useful for decreasing or even stopping vestibular spatial disorientation. PMID:24834571

  2. Functional stochastic resonance in human baroreflex induced by 1/f-type noisy galvanic vestibular stimulation

    Soma, Rika; Kwak, Shin; Yamamoto, Yoshiharu

    2003-05-01

    We hypothesized that 1/f noise is more beneficial than the conventional white noise in optimizing the brain's response to a weak input signal, and showed that externally added 1/f noise outperforms white noise in sensitizing human baroreflex centers in the brain. We examined the compensatory heart rate response to weak periodic signal introduced at the venous blood pressure receptor, while adding either 1/f or white noise with the same variance to the brain stem by electrically stimulating the bilateral vestibular afferents cutaneously. This stochastic galvanic vestibular stimulation, activating the vestibulo-sympathetic pathway in the brain stem, optimized covariance between weak input signals and the heart rate responses both with 1/f and white noise. Further, the optimal noise level with 1/f noise was significantly lower than that with white noise, suggesting the functional benefit of 1/f noise for the neuronal information transfer in the brain.

  3. Eye movement and vestibular dysfunction in mitochondrial A3243G mutation.

    Kim, Sung-Hee; Akbarkhodjaeva, Ziyoda Abdulkhaevna; Jung, Ileok; Kim, Ji-Soo

    2016-07-01

    Studying eye movements and vestibular function would provide insights into brain networks that are vulnerable in mitochondrial disorders. We sought eye movement and vestibular abnormalities in three Korean patients with a mitochondrial A3243G point mutation. The patients suffered from vertigo and imbalance during the stroke-like and seizure episodes from lesions involving the posterior cerebral cortex, which were accompanied by bilateral saccadic hypermetria and horizontal gaze-evoked nystagmus. Furthermore, two patients showed bilateral impairments of the vestibulo-ocular reflex during head impulses for the horizontal and posterior canals on both sides in the absence of caloric paresis. Cerebellar atrophy was prominent on MRIs in two patients and was less marked in the other patient. These findings imply that the cerebellum is susceptible to neuronal energy deficiency due to mitochondrial A3243G point mutation. PMID:27075643

  4. Can a finding of cervical vestibular evoked myogenic potentials contribute to vestibular migraine diagnostics?

    Tihana Vešligaj

    2016-02-01

    Full Text Available Aim To investigate differences in vestibular evoked myogenic potentials (VEMP results with patients suffering from vestibular migraine and healthy people, taking into consideration values of threshold and latency of occurrence of the characteristic wave complex, size of amplitude, and interaural amplitude ratio. According to the results, determine the importance and usefulness of VEMP in vestibular migraine diagnostics. Methods A total number of 62 subjects were included in the study, 32 of them belonging to a group of patients suffering from vestibular migraine (VM, while other 30 were in a control group of healthy subjects. Information was collected during the diagnostic evaluation. General and otoneurological history of patients and bedside tests, audiological results, videonystagmography and cervical vestibular evoked myogenic potentials (cVEMP were made. Results There was a difference in an interaural ratio of amplitudes in the experimental and control groups, but it was not found to be clinically significant. By ToneBurst 500 Hz method, the interaural amplitude ratio higher than 35% was measured in 46.97% subjects, while the response was totally unilaterally missing in 28.8% patients. Conclusion Even the sophisticated method as cVEMP does not give the ultimate result confirming the vestibular migraine diagnosis, and neither do other diagnostic methods. cVEMP result can contribute to the completion of full mosaic of vestibular migraine diagnostics.

  5. Vestibular Schwannoma or acoustic neuroma

    Hekmatara M

    1997-04-01

    Full Text Available Vestibular schwannoma is the most common tumor of the posterior fossa of the skull. Patients referred with the primary otologic symptoms such as hearing loss, tinnitus, vertigo, imbalance, and the cranial nerve palsy. Thirty-three patients were operated and treated by a team of otolaryngologist and neurosurgeon, anudiometrist, and internist. Patients'chiefcomplaint was due to 94% hearing loss and 27% tinnitus. They scarcely complain of vertigo. If a patient refers with the palsy or paralysis of facial nerve preoperation, we must think of the facial nerve schwannoma or hemangioma or congential cholestoma or malignant metastases rather than acoustic neuroma. The best way for preoperative diagnosis is audiometry, ABR (Auditory Brain Response, and SDS (speech discrimination score with 90% success, but computer Tomography (CT scan and MRI (Magnetic Resonance Image are the valuable anatomic diagnostic radiographic devices. The best method of operation is translabirynthine approach (TLA, since it has the advantages such as an easy access to nerve paths and being the nearest path to CPA (Cerebellopontine Angle. Physicians ought to talk to patients about the importance of the microscopic surgery, surgical methods, and their probable diverse effects such as hearing loss, facial nerve palsy, and intracranial problems.

  6. Spontaneous shrinkage of vestibular schwannoma

    Romani, Rossana; Pollock, Jonathan

    2016-01-01

    Background: “Watch, wait, and rescan” (WWR) has an established place as a successful management option for a significant proportion of vestibular schwannomas (VS) as an alternative to microsurgical removal or stereotactic radiotherapy. VS may grow slowly and continuously, followed by stagnation or even shrinkage. We present two case reports of spontaneous shrinkage of VS along with a review of the literature. Case Description: A 29-year-old female presented with a progressive history of visual blurring and intermittent diplopia over 2 months. A 29 mm of maximum intracranial diameter (ICD) VS with secondary obstructive hydrocephalus was diagnosed. The patient underwent a ventriculo-peritoneal shunt with resolution of her symptoms and opted for initial WWR management. Interval scanning between 2007 and 2014 showed progressive reduction in the maximum ICD together with reduction in the degree of central tumor enhancement. Maximum ICD at most recent follow up was 22 mm. A 28-year-old female was referred with right sensorineural deafness. A right VS of maximum ICD of 27 mm was diagnosed. Initial WWR management was planned after discussion. Serial imaging showed an initial increase in the size of the tumor followed by progressive reduction in size. The most recent follow up showed a maximum ICD of 20 mm. Conclusion: Early WWR management can be associated with spontaneous shrinkage of VS over time. Prospective clinical study of larger numbers of such cases using the UK VS database may help to identify predictive factors for the spontaneous regression of VS. PMID:27280055

  7. Optical nerve stimulation for a vestibular prosthesis

    Harris, David M.; Bierer, Steven M.; Wells, Jonathon D.; Phillips, James O.

    2009-02-01

    Infrared Nerve Stimulation (INS) offers several advantages over electrical stimulation, including more precise spatial selectivity and improved surgical access. In this study, INS and electrical stimulation were compared in their ability to activate the vestibular branch of the VIIIth nerve, as a potential way to treat balance disorders. The superior and lateral canals of the vestibular system of Guinea pigs were identified and approached with the aid of precise 3-D reconstructions. A monopolar platinum stimulating electrode was positioned near the ampullae of the canals, and biphasic current pulses were used to stimulate vestibular evoked potentials and eye movements. Thresholds and input/output functions were measured for various stimulus conditions. A short pulsed diode laser (Capella, Lockheed Martin-Aculight, Inc., Bothell WA) was placed in the same anatomical position and various stimulus conditions were evaluated in their ability to evoke similar potentials and eye movements.

  8. The nucleus of the optic tract. Its function in gaze stabilization and control of visual-vestibular interaction

    Cohen, B.; Reisine, H.; Yokota, J. I.; Raphan, T.

    1992-01-01

    1. Electrical stimulation of the nucleus of the optic tract (NOT) induced nystagmus and after-nystagmus with ipsilateral slow phases. The velocity characteristics of the nystagmus were similar to those of the slow component of optokinetic nystagmus (OKN) and to optokinetic after-nystagmus (OKAN), both of which are produced by velocity storage in the vestibular system. When NOT was destroyed, these components disappeared. This indicates that velocity storage is activated from the visual system through NOT. 2. Velocity storage produces compensatory eye-in-head and head-on-body movements through the vestibular system. The association of NOT with velocity storage implies that NOT helps stabilize gaze in space during both passive motion and active locomotion in light with an angular component. It has been suggested that "vestibular-only" neurons in the vestibular nuclei play an important role in generation of velocity storage. Similarities between the rise and fall times of eye velocity during OKN and OKAN to firing rates of vestibular-only neurons suggest that these cells may receive their visual input through NOT. 3. One NOT was injected with muscimol, a GABAA agonist. Ipsilateral OKN and OKAN were lost, suggesting that GABA, which is an inhibitory transmitter in NOT, acts on projection pathways to the brain stem. A striking finding was that visual suppression and habituation of contralateral slow phases of vestibular nystagmus were also abolished after muscimol injection. The latter implies that NOT plays an important role in producing visual suppression of the VOR and habituating its time constant. 4. Habituation is lost after nodulus and uvula lesions and visual suppression after lesions of the flocculus and paraflocculus. We postulate that the disappearance of vestibular habituation and of visual suppression of vestibular responses after muscimol injections was due to dysfacilitation of the prominent NOT-inferior olive pathway, inactivating climbing fibers from

  9. RECORDING OF VESTIBULAR EVOKED MYOGENIC POTENTIALS

    A. A. Sazgar

    2006-05-01

    Full Text Available It has been shown recently that loud clicks evoke myogenic potentials in the tonically contracting sternocleidomastoid muscles. Studies have suggested that these potentials are of vestibular origin, especially of the saccule and inferior vestibular nerve. A pilot study was undertaken in our hospital to record vestibular evoked myogenic potentials (VEMP for the first time in Iran. Eighteen healthy volunteers (32 ears without history of otologic or vestibular disorders were subjected to the VEMP test. Twenty-one patients (26 ears with unilateral (6 patients and bilateral (5 patients high frequency sensorineural hearing loss with unknown etiology, acoustic neuroma (1 patient, Meniere’s disease (4 patients and unilateral low frequency sensorineural hearing loss without vestibular complaint (5 patients were also enrolled in this study. VEMP response to clicks was obtained from 84.4% of ears of healthy subjects. These subjects demonstrated short latency waves to click stimuli during tonic neck flexor activation. Mean latencies of first positive (p13 and first negative (n23 potentials in healthy subjects were 12.45 ± 1.9 ms and 20.8 ± 3.5 ms, respectively. Median latencies of these two potentials were 12.1 and 19.3 ms, respectively. We could record VEMP in 5 patients with unilateral and all patients with high and low frequency sensorineural hearing loss without vestibular complaint. In the patient with acoustic neuroma VEMP was absent on the affected side. This technique may offer a new method to evaluate otolith and sacculocollic pathways in human.

  10. Recovery of vestibular function following hair cell destruction by streptomycin

    Jones, T. A.; Nelson, R. C.

    1992-01-01

    Can the vestibular periphery of warm-blooded vertebrates recover functionally from severe sensory hair cell loss? Recent findings in birds suggest a mechanism for recovery but in fact no direct functional evidence has been reported. We produced vestibular hair cell lesions using the ototoxic agent streptomycin sulfate (600 mg/kg/day, 8 days, chicks, Gallus domesticus). Compound action potentials of the vestibular nerve were used as a direct measure of peripheral vestibular function. Vestibular thresholds, neural activation latencies and amplitudes were documented. Eight days of drug treatment elevated thresholds significantly (P morphologies including activation latencies and amplitudes required an additional 6-8 weeks.

  11. Vestibular schwannoma: anatomical, medical and surgical perspective

    Ashfaq Ul Hassan

    2013-06-01

    Full Text Available The term "acoustic" is a misnomer, as the tumor rarely arises from the acoustic (or cochlear division of the vestibulocochlear nerve. The correct medical term is vestibular schwannoma, because it involves the vestibular portion of the 8th cranial nerve. They are benign, rather rare tumors. They expand in size and grow larger; they can push against the brain. While the tumor does not actually invade the brain, the pressure of the tumor can displace brain tissue. [Int J Res Med Sci 2013; 1(3.000: 178-182

  12. Outcome after translabyrinthine surgery for vestibular schwannomas

    Springborg, Jacob Bertram; Fugleholm, Kåre; Poulsgaard, Lars;

    2012-01-01

    The objective of this article is to study the outcome after translabyrinthine surgery for vestibular schwannomas, with special focus on the facial nerve function. The study design is a case series from a national centralized database and it is set in two University Hospitals in Denmark. Participa......The objective of this article is to study the outcome after translabyrinthine surgery for vestibular schwannomas, with special focus on the facial nerve function. The study design is a case series from a national centralized database and it is set in two University Hospitals in Denmark...

  13. Vestibular migraine: diagnosis challenges and need for targeted treatment.

    Barbosa, Felipe; Villa, Thaís Rodrigues

    2016-05-01

    Approximately 1% of the general population suffers from vestibular migraine. Despite the recently published diagnostic criteria, it is still underdiagnosed condition. The exact neural mechanisms of vestibular migraine are still unclear, but the variability of symptoms and clinical findings both during and between attacks suggests an important interaction between trigeminal and vestibular systems. Vestibular migraine often begins several years after typical migraine and has a variable clinical presentation. In vestibular migraine patients, the neurological and neurotological examination is mostly normal and the diagnosis will be based in the patient clinical history. Treatment trials that specialize on vestibular migraine are scarce and therapeutic recommendations are based on migraine guidelines. Controlled studies on the efficacy of pharmacologic interventions in the treatment of vestibular migraine should be performed. PMID:27191239

  14. From ear to uncertainty: Vestibular contributions to cognitive function.

    Paul eSmith

    2013-11-01

    Full Text Available In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and cortex play in spatial orientation. In this review we summarise the evidence that vestibular loss causes cognitive disorders, especially spatial memory deficits, in animals and humans and critically evaluate the evidence that these deficits are not due to hearing loss, problems with motor control, oscillopsia or anxiety and depression. We review the evidence that vestibular lesions affect head direction and place cells as well as the emerging evidence that artificial activation of the vestibular system, using galvanic vestibular stimulation, can modulate cognitive function.

  15. From ear to uncertainty: vestibular contributions to cognitive function.

    Smith, Paul F; Zheng, Yiwen

    2013-01-01

    In addition to the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, there is substantial evidence that vestibular loss also causes cognitive disorders, some of which may be due to the reflexive deficits and some of which are related to the role that ascending vestibular pathways to the limbic system and neocortex play in spatial orientation. In this review we summarize the evidence that vestibular loss causes cognitive disorders, especially spatial memory deficits, in animals and humans and critically evaluate the evidence that these deficits are not due to hearing loss, problems with motor control, oscillopsia or anxiety and depression. We review the evidence that vestibular lesions affect head direction and place cells as well as the emerging evidence that artificial activation of the vestibular system, using galvanic vestibular stimulation (GVS), can modulate cognitive function. PMID:24324413

  16. Loss of Afferent Vestibular Input Produces Central Adaptation and Increased Gain of Vestibular Prosthetic Stimulation.

    Phillips, Christopher; Shepherd, Sarah J; Nowack, Amy; Nie, Kaibao; Kaneko, Chris R S; Rubinstein, Jay T; Ling, Leo; Phillips, James O

    2016-02-01

    Implanted vestibular neurostimulators are effective in driving slow phase eye movements in monkeys and humans. Furthermore, increases in slow phase velocity and electrically evoked compound action potential (vECAP) amplitudes occur with increasing current amplitude of electrical stimulation. In intact monkeys, protracted intermittent stimulation continues to produce robust behavioral responses and preserved vECAPs. In lesioned monkeys, shorter duration studies show preserved but with somewhat lower or higher velocity behavioral responses. It has been proposed that such changes are due to central adaptive changes in the electrically elicited vestibulo-ocular reflex (VOR). It is equally possible that these differences are due to changes in the vestibular periphery in response to activation of the vestibular efferent system. In order to investigate the site of adaptive change in response to electrical stimulation, we performed transtympanic gentamicin perfusions to induce rapid changes in vestibular input in monkeys with long-standing stably functioning vestibular neurostimulators, disambiguating the effects of implantation from the effects of ototoxic lesion. Gentamicin injection was effective in producing a large reduction in natural VOR only when it was performed in the non-implanted ear, suggesting that the implanted ear contributed little to the natural rotational response before injection. Injection of the implanted ear produced a reduction in the vECAP responses in that ear, suggesting that the intact hair cells in the non-functional ipsilateral ear were successfully lesioned by gentamicin, reducing the efficacy of stimulation in that ear. Despite this, injection of both ears produced central plastic changes that resulted in a dramatically increased slow phase velocity nystagmus elicited by electrical stimulation. These results suggest that loss of vestibular afferent activity, and a concurrent loss of electrically elicited vestibular input, produces an

  17. Determining the direction of vestibular-evoked balance responses using stochastic vestibular stimulation

    Mian, O. S.; Day, B. L.

    2009-01-01

    As a tool for investigating vestibulo-motor function, stochastic vestibular stimulation (SVS) has some advantages over galvanic vestibular stimulation. However, there is no technique currently available for extracting direction information from SVS-evoked motor responses. It is essential to be able to measure the direction of response if one wishes to investigate the operation of key spatial transformation processes in the brain. Here we describe and validate a technique for determining the d...

  18. Galvanic vestibular stimulation: a novel modulatory countermeasure for vestibular-associated movement disorders

    Rizzo-Sierra, Carlos V; Alexander Gonzalez-Castaño; Leon-Sarmiento, Fidias E

    2014-01-01

    Motion sickness or kinetosis is the result of the abnormal neural output originated by visual, proprioceptive and vestibular mismatch, which reverses once the dysfunctional sensory information becomes coherent. The space adaptation syndrome or space sickness relates to motion sickness; it is considered to be due to yaw, pith, and roll coordinates mismatch. Several behavioural and pharmacological measures have been proposed to control these vestibular-associated movement disorders with no succ...

  19. Asymmetry of balance responses to monaural galvanic vestibular stimulation in subjects with vestibular schwannoma ☆

    Welgampola, M. S.; Ramsay, E.; Gleeson, M. J.; Day, B. L.

    2013-01-01

    Objective We investigated the potential of galvanic vestibular stimulation (GVS) to quantify lateralised asymmetry of the vestibulospinal pathways by measuring balance responses to monaural GVS in 10 subjects with vestibular schwannoma and 22 healthy control subjects. Methods Subjects standing without vision were stimulated with 3 s, 1 mA direct current stimuli delivered monaurally. The mean magnitude and direction of the evoked balance responses in the horizontal plane were measured from gro...

  20. Nonneuronal cells regulate synapse formation in the vestibular sensory epithelium via erbB-dependent BDNF expression

    Gómez-Casati, Maria E; MURTIE, JOSHUA C.; Rio, Carlos; Stankovic, Konstantina; Liberman, M. Charles; Corfas, Gabriel

    2010-01-01

    Recent studies indicate that molecules released by glia can induce synapse formation. However, what induces glia to produce such signals, their identity, and their in vivo relevance remain poorly understood. Here we demonstrate that supporting cells of the vestibular organ—cells that have many characteristics of glia—promote synapse formation only when induced by neuron-derived signals. Furthermore, we identify BDNF as the synaptogenic signal produced by these nonneuronal cells. Mice in which...

  1. Vestibular Dysfunctions in Cochlear Implant Patients; A Vestibular Evoked Myogenic Potential Study

    Masoud Motasaddi Zarandy

    2011-12-01

    Full Text Available Background and Aim: Vestibular evoked myogenic potential in response to click or short tone burst stimuli have been used as a clinical test for distinguish saccule and inferior vestibular nerve diseases. Different studies show that cochlear implant could have inverse effects on vestibular structures. We aimed to investigate vestibular evoked myogenic potential in unilateral cochlear implanted individuals in compare to normal individuals.Methods: Thirty-three unilateral cochlear implanted patients (mean age 19.96 years and 30 normal hearing individuals (mean age 24-27 years as control group were enrolled in this cross- sectional study. Absolute latencies and amplitudes of myogenic potential responses were measured and compared in both groups.Results: Myogenic potential recorded in both ears of all controls were normal. No response could be recorded in 16 patients (48.48% from both ears. In three patients, responses were recorded in both ears though the amplitude of waves was reduced in implanted ear. Unilateral response could be recorded in 14 patients only in their non-implanted ear.Conclusion: Vestibular evoked myogenic potential test is a useful tool for assessing saccular function in cochlear implant patients. Damages of osseous spiral lamina and basilar membrane after cochlear implantation could result in dysfunctions of vestibular organs specially saccule. It seems that saccule could be easily damaged after cochlear implantation. This would cause absence or reduced amplitudes in myogenic potential.

  2. Vestibular stimulation leads to distinct hemodynamic patterning

    Kerman, I. A.; Emanuel, B. A.; Yates, B. J.

    2000-01-01

    Previous studies demonstrated that responses of a particular sympathetic nerve to vestibular stimulation depend on the type of tissue the nerve innervates as well as its anatomic location. In the present study, we sought to determine whether such precise patterning of vestibulosympathetic reflexes could lead to specific hemodynamic alterations in response to vestibular afferent activation. We simultaneously measured changes in systemic blood pressure and blood flow (with the use of Doppler flowmetry) to the hindlimb (femoral artery), forelimb (brachial artery), and kidney (renal artery) in chloralose-urethane-anesthetized, baroreceptor-denervated cats. Electrical vestibular stimulation led to depressor responses, 8 +/- 2 mmHg (mean +/- SE) in magnitude, that were accompanied by decreases in femoral vasoconstriction (23 +/- 4% decrease in vascular resistance or 36 +/- 7% increase in vascular conductance) and increases in brachial vascular tone (resistance increase of 10 +/- 6% and conductance decrease of 11 +/- 4%). Relatively small changes (vasoconstriction in all three beds. These data suggest that vestibular inputs lead to a complex pattern of cardiovascular changes that is distinct from that which occurs in response to activation of other types of somatic afferents.

  3. Cervical vestibular evoked myogenic potentials in children

    Alcione Botelho Pereira

    2015-08-01

    Full Text Available INTRODUCTION: Cervical vestibular evoked myogenic potential is a test used in neurotological examination. It verifies the integrity of vestibular function through a muscular response evoked by an acoustic stimulation which activates the saccular macula. Normal standards in adults have been established, however, there are few published data on the normal responses in children.OBJECTIVE: To establish normal standards for vestibular myogenic responses in children without neurotological complaints.METHODS: This study's design is a cohort with cross-sectional analysis. The sample consisted of 30 subjects, 15 females (50% and 15 males (50%.RESULTS: The age of the subjects ranged between 8 and 13 years, with a mean of 10.2 (± 1.7. P1 peak showed an average latency of 17.26 (± 1.78 ms and a mean amplitude of 49.34 (± 23.07 µV, and the N2 peak showed an average latency of 24.78 (± 2.18 ms and mean amplitude of 66.23 (± 36.18 µV. P1-N2 mean amplitude was 115.6 (± 55.7 µV. There were no statistically significant differences when comparing by gender or by laterality.CONCLUSION: We established normal values of cervical myogenic vestibular responses in children between 8 and 13 years without neurotological complaints.

  4. Perspectives in vestibular diagnostics and therapy [

    Ernst, Arneborg

    2012-04-01

    Full Text Available [english] Vestibular diagnostics and therapy ist the mirror of technological, scientific and socio-economics trends as are other fields of clinical medicine. These trends have led to a substantial diversification of the field of neurotology.The improvements in diagnostics have been characterized by the introduction of new receptor testing tools (e.g., VEMPs, progress in imaging (e.g., the endolymphatic hydrops and in the description of central-vestibular neuroplasticity. The etiopathology of vestibular disorders has been updated by geneticists (e.g., the description of the COCH gene mutations, the detection of structural abnormalities (e.g., dehiscence syndromes and related disorders (e.g. migraine-associated vertigo. The therapeutic options were extended by re-evaluation of techniques known a long time ago (e.g., saccus exposure, the development of new approaches (e.g., dehiscence repair and the introduction of new drug therapy concepts (e.g., local drug delivery. Implantable, neuroprosthetic solutions have not yet reached experimental safety and validity and are still far away. However, externally worn neuroprosthetic solution were introduced in the rehab of vestibular disorders (e.g., VertiGuard system.These and related trends point into a medical future which is characterized by presbyvertigo as classical sign of the demographic changes ahead, by shortage of financial resources and a medico-legally over-regulated, even hostile environment for physicians in clinical medicine.

  5. Response to Vestibular Sensory Events in Autism

    Kern, Janet K.; Garver, Carolyn R.; Grannemann, Bruce D.; Trivedi, Madhukar H.; Carmody, Thomas; Andrews, Alonzo A.; Mehta, Jyutika A.

    2007-01-01

    The purpose of this study was to examine the response to vestibular sensory events in persons with autism. The data for this study was collected as part of a cross-sectional study that examined sensory processing (using the Sensory Profile) in 103 persons with autism, 3-43 years of age, compared to age- and gender-matched community controls. The…

  6. Cell Death, Neuronal Plasticity and Functional Loading in the Development of the Central Nervous System

    Keefe, J. R.

    1985-01-01

    Research on the precise timing and regulation of neuron production and maturation in the vestibular and visual systems of Wistar rats and several inbred strains of mice (C57B16 and Pallid mutant) concentrated upon establishing a timing baseline for mitotic development of the neurons of the vestibular nuclei and the peripheral vestibular sensory structures (maculae, cristae). This involved studies of the timing and site of neuronal cell birth and preliminary studies of neuronal cell death in both central and peripheral elements of the mammalian vestibular system. Studies on neuronal generation and maturation in the retina were recently added to provide a mechanism for more properly defining the in utero' developmental age of the individual fetal subject and to closely monitor potential transplacental effects of environmentally stressed maternal systems. Information is given on current efforts concentrating upon the (1) perinatal period of development (E18 thru P14) and (2) the role of cell death in response to variation in the functional loading of the vestibular and proprioreceptive systems in developing mammalian organisms.

  7. Swimming Behavior and Calcium Incorporation into inner Ear Otoliths of Fish after vestibular Nerve Transection

    Edelmann, E.; Anken, R.; Rahmann, H.

    Previous investigations on neonate swordtail fish (Xiphophorus helleri) revealed that otolithic calcium incorporation (visualized using the calcium-tracer alizarin- complexone) and thus otolith growth had ceased after nerve transection, supporting a hypothesis according to which the gravity-dependent otolith growth is regulated neuronally. Subsequent investigations on larval cichlid fish (Oreochromis mossambicus) yielded contrasting results, repeatedly depending on the particular batch of cichlids investigated: Like neonate swordtails, type I cichlids revealed a stop of calcium incorporation after unilateral vestibular nerve transection. Their behaviour after transection was normal and the otolithic calcium incorporation in controls of the same batch was symmetrical. In type II cichlids, however, vestibular nerve transection had no effect on otolithic calcium incorporation. They behaved kinetotically after transection (this kind of kinetosis was qualitatively similar to the swimming behaviour exhibited by larval cichlids during microgravity in the course of parabolic aircraft flights). The otolithic calcium incorporation in control animals was asymmetrical. These results stongly suggest that the effects of vestibular nerve transection as well as the efficacy of the mechanism, which regulates otolith growth/otolithic calcium incorporation, are - depending on the particular batch of animals - genetically predispositioned. Thus, it is assumed that the mechanisms regulating otolith growth and equlibibrium differ in the two types of cichlid fish. This work was financially supported by the German Aerospace Center (DLR) e.V. (FKZ: 50 WB 9997).

  8. Vestibular loss and balance training cause similar changes in human cerebral white matter fractional anisotropy.

    Nadine Hummel

    Full Text Available Patients with bilateral vestibular loss suffer from severe balance deficits during normal everyday movements. Ballet dancers, figure skaters, or slackliners, in contrast, are extraordinarily well trained in maintaining balance for the extreme balance situations that they are exposed to. Both training and disease can lead to changes in the diffusion properties of white matter that are related to skill level or disease progression respectively. In this study, we used diffusion tensor imaging (DTI to compare white matter diffusivity between these two study groups and their age- and sex-matched controls. We found that vestibular patients and balance-trained subjects show a reduction of fractional anisotropy in similar white matter tracts, due to a relative increase in radial diffusivity (perpendicular to the main diffusion direction. Reduced fractional anisotropy was not only found in sensory and motor areas, but in a widespread network including long-range connections, limbic and association pathways. The reduced fractional anisotropy did not correlate with any cognitive, disease-related or skill-related factors. The similarity in FA between the two study groups, together with the absence of a relationship between skill or disease factors and white matter changes, suggests a common mechanism for these white matter differences. We propose that both study groups must exert increased effort to meet their respective usual balance requirements. Since balance training has been shown to effectively reduce the symptoms of vestibular failure, the changes in white matter shown here may represent a neuronal mechanism for rehabilitation.

  9. Calyx and dimorphic neurons of mouse Scarpa's ganglion express histamine H3 receptors

    Zucca Gianpiero

    2009-06-01

    Full Text Available Abstract Background Histamine-related drugs are commonly used in the treatment of vertigo and related vestibular disorders. The site of action of these drugs however has not been elucidated yet. Recent works on amphibians showed that histamine H3 receptor antagonists, e.g. betahistine, inhibit the afferent discharge recorded from the vestibular nerve. To assess the expression of H3 histamine receptors in vestibular neurons, we performed mRNA RT-PCR and immunofluorescence experiments in mouse Scarpa's ganglia. Results RT-PCR analysis showed the presence of H3 receptor mRNA in mouse ganglia tissue. H3 protein expression was found in vestibular neurons characterized by large and roundish soma, which labeled for calretinin and calbindin. Conclusion The present results are consistent with calyx and dimorphic, but not bouton, afferent vestibular neurons expressing H3 receptors. This study provides a molecular substrate for the effects of histamine-related antivertigo drugs acting on (or binding to H3 receptors, and suggest a potential target for the treatment of vestibular disorders of peripheral origin.

  10. Functional and anatomic alterations in the gentamicin-damaged vestibular system in the guinea pig

    Oei, MLYM; Segenhout, HM; Dijk, T; Stokroos, [No Value; van der Want, TJL; Albers, FWJ

    2004-01-01

    Hypothesis: The purpose of this study was to investigate the expected functional and morphologic effect of gentamicin on the vestibular system simultaneously by measurement of vestibular evoked potentials and electron microscopic evaluation. Background: Vestibular short-latency evoked potentials to

  11. Exhibition of Stochastic Resonance in Vestibular Perception

    Galvan-Garza, R. C.; Clark, T. K.; Merfeld, D. M.; Bloomberg, J. J.; Oman, C. M.; Mulavara, A. P.

    2016-01-01

    Astronauts experience sensorimotor changes during spaceflight, particularly during G-transitions. Post flight sensorimotor changes include spatial disorientation, along with postural and gait instability that may degrade operational capabilities of the astronauts and endanger the crew. A sensorimotor countermeasure that mitigates these effects would improve crewmember safety and decrease risk. The goal of this research is to investigate the potential use of stochastic vestibular stimulation (SVS) as a technology to improve sensorimotor function. We hypothesize that low levels of SVS will improve sensorimotor perception through the phenomenon of stochastic resonance (SR), when the response of a nonlinear system to a weak input signal is enhanced by the application of a particular nonzero level of noise. This study aims to advance the development of SVS as a potential countermeasure by 1) demonstrating the exhibition of stochastic resonance in vestibular perception, a vital component of sensorimotor function, 2) investigating the repeatability of SR exhibition, and 3) determining the relative contribution of the semicircular canals (SCC) and otolith (OTO) organs to vestibular perceptual SR. A constant current stimulator was used to deliver bilateral bipolar SVS via electrodes placed on each of the mastoid processes, as previously done. Vestibular perceptual motion recognition thresholds were measured using a 6-degree of freedom MOOG platform and a 150 trial 3-down/1-up staircase procedure. In the first test session, we measured vestibular perceptual thresholds in upright roll-tilt at 0.2 Hz (SCC+OTO) with SVS ranging from 0-700 µA. In a second test session a week later, we re-measured roll-tilt thresholds with 0, optimal (from test session 1), and 1500 µA SVS levels. A subset of these subjects, plus naive subjects, participated in two additional test sessions in which we measured thresholds in supine roll-rotation at 0.2 Hz (SCC) and upright y-translation at 1 Hz

  12. Characterization of pulse amplitude and pulse rate modulation for a human vestibular implant during acute electrical stimulation

    Nguyen, T. A. K.; DiGiovanna, J.; Cavuscens, S.; Ranieri, M.; Guinand, N.; van de Berg, R.; Carpaneto, J.; Kingma, H.; Guyot, J.-P.; Micera, S.; Perez Fornos, A.

    2016-08-01

    Objective. The vestibular system provides essential information about balance and spatial orientation via the brain to other sensory and motor systems. Bilateral vestibular loss significantly reduces quality of life, but vestibular implants (VIs) have demonstrated potential to restore lost function. However, optimal electrical stimulation strategies have not yet been identified in patients. In this study, we compared the two most common strategies, pulse amplitude modulation (PAM) and pulse rate modulation (PRM), in patients. Approach. Four subjects with a modified cochlear implant including electrodes targeting the peripheral vestibular nerve branches were tested. Charge-equivalent PAM and PRM were applied after adaptation to baseline stimulation. Vestibulo-ocular reflex eye movement responses were recorded to evaluate stimulation efficacy during acute clinical testing sessions. Main results. PAM evoked larger amplitude eye movement responses than PRM. Eye movement response axes for lateral canal stimulation were marginally better aligned with PRM than with PAM. A neural network model was developed for the tested stimulation strategies to provide insights on possible neural mechanisms. This model suggested that PAM would consistently cause a larger ensemble firing rate of neurons and thus larger responses than PRM. Significance. Due to the larger magnitude of eye movement responses, our findings strongly suggest PAM as the preferred strategy for initial VI modulation.

  13. Galvanic vestibular stimulation impairs cell proliferation and neurogenesis in the rat hippocampus but not spatial memory.

    Zheng, Yiwen; Geddes, Lisa; Sato, Go; Stiles, Lucy; Darlington, Cynthia L; Smith, Paul F

    2014-05-01

    Galvanic vestibular stimulation (GVS) is a method of activating the peripheral vestibular system using direct current that is widely employed in clinical neurological testing. Since movement is recognized to stimulate hippocampal neurogenesis and movement is impossible without activation of the vestibular system, we speculated that activating the vestibular system in rats while minimizing movement, by delivering GVS under anesthesia, would affect hippocampal cell proliferation and neurogenesis, and spatial memory. Compared with the sham control group, the number of cells incorporating the DNA replication marker, bromodeoxyuridine (BrdU), was significantly reduced in the bilateral hippocampi in both the cathode left-anode right and cathode right-anode left stimulation groups (P ≤ 0.0001). The majority of the BrdU(+ve) cells co-expressed Ki-67, a marker for the S phase of the cell cycle, suggesting that these BrdU(+ve) cells were still in the cell cycle; however, there was no significant difference in the degree of co-labeling between the two stimulation groups. Single labeling for doublecortin (DCX), a marker of immature neurons, showed that while there was no significant difference between the different groups in the number of DCX(+ve) cells in the right dentate gryus, in the left dentate gyrus there was a significant decrease in the cathode left-anode right group compared with the sham controls (P ≤ 0.03). Nonetheless, when animals were tested in place recognition, object exploration and Morris water maze tasks, there were no significant differences between the GVS groups and the sham controls. These results suggest that GVS can have striking effects on cell proliferation and possibly neurogenesis in the hippocampus, without affecting spatial memory. PMID:24449222

  14. Interactions between Stress and Vestibular Compensation – A Review

    MayankBDutia; YouganSaman; DorisBamiou

    2012-01-01

    Elevated levels of stress and anxiety often accompany vestibular dysfunction, while conversely complaints of dizziness and loss of balance are common in patients with panic and other anxiety disorders. The interactions between stress and vestibular function, and plasticity have been investigated both in animal models and in clinical studies. Evidence from animal studies indicates that vestibular symptoms are effective in activating the stress axis, and that the acute stress response is import...

  15. Vestibular hypersensitivity to clicks is characteristic of the Tullio phenomenon

    Colebatch, J; Day, B.; Bronstein, A; Davies, R.; Gresty, M.; Luxon, L; Rothwell, J

    1998-01-01

    OBJECTIVES—The frequency of pathologically reduced click thresholds for vestibular activation was explored in patients with the Tullio phenomenon (sound induced vestibular activation).
METHODS—Seven patients (eight affected ears) with symptoms of oscillopsia and unsteadiness in response to loud external sounds or to the patient's own voice were examined. In all but one patient, vestibular hypersensitivity to sound was confirmed by the fact that eye movements could be produced b...

  16. How vestibular stimulation interacts with illusory hand ownership

    Lopez, Christophe; Lenggenhager, Bigna; Blanke, Olaf

    2010-01-01

    Artificial stimulation of the peripheral vestibular system has been shown to improve ownership of body parts in neurological patients, suggesting vestibular contributions to bodily self-consciousness. Here, we investigated whether galvanic vestibular stimulation (GVS) interferes with the mechanisms underlying ownership, touch, and the localization of one's own hand in healthy participants by using the "rubber hand illusion" paradigm. Our results show that left anodal GVS increases illusory ow...

  17. Reversible tobramycin-induced bilateral high-frequency vestibular toxicity.

    Walsh, R M; Bath, A P; Bance, M L

    2000-01-01

    We report an unusual case of tobramycin-induced bilateral high-frequency vestibular toxicity with subsequent clinical and objective evidence of functional recovery. In those patients with a clinical presentation suggestive of aminoglycoside-induced bilateral vestibular toxicity (ataxia and oscillopsia) and normal low-frequency (ENG-caloric) responses, high-frequency rotation chair testing should be performed to exclude a high-frequency vestibular deficit. PMID:10810261

  18. Influence of temperature on the sound-evoked vestibular potential.

    Wit, H P; Dijkgraaf, E

    1985-01-01

    The sound-evoked vestibular potential, measured with gross electrodes after fenestration of a lateral semicircular canal in pigeons, is delayed with respect to the acoustic stimulus. The influence of temperature of the vestibular system on this delay can most easily be explained by assuming chemically mediated transmission to take place between vestibular hair cells and their primary afferents. The possibility of electrotonic transmission, however, cannot be excluded. PMID:3878654

  19. Periosteal Pedicle Flap Harvested during Vestibular Extension for Root Coverage

    Shubham Kumar

    2015-01-01

    Full Text Available Root exposure along with inadequate vestibular depth is a common clinical finding. Treatment option includes many techniques to treat such defects for obtaining predictable root coverage. Normally, the vestibular depth is increased first followed by a second surgery for root coverage. The present case report describes a single-stage technique for vestibular extension and root coverage in a single tooth by using the Periosteal Pedicle Flap (PPF. This technique involves no donor site morbidity and allows for reflection of sufficient amount of periosteal flap tissue with its own blood supply at the surgical site, thus increasing the chances of success of root coverage with simultaneous increase in vestibular depth.

  20. Clinical application of vestibular evoked myogenic potential (VEMP).

    Murofushi, Toshihisa

    2016-08-01

    The author reviewed clinical aspects of vestibular evoked myogenic potentials (VEMPs). Now two types of VEMPs are available. The first one is cervical VEMP, which is recorded in the sternocleidomastoid muscle and predominantly reflects sacculo-collic reflex. The other is ocular VEMP, which is usually recorded below the lower eye lid and predominantly reflects utriculo-ocular reflex. VEMPs play important roles not only for assessment of common vestibular diseases but also for establishment of new clinical entities. Clinical application in Meniere's disease, vestibular neuritis, benign paroxysmal positional vertigo, vestibular migraine, idiopathic otolithic vertigo, and central vertigo/dizziness was reviewed. PMID:26791591

  1. Experiment M131. Human vestibular function

    Graybiel, A.; Miller, E. F., II; Homick, J. L.

    1977-01-01

    The lower susceptibility to vestibular stimulation aloft, compared with that on ground under experimental conditions, is attributed to a precondition, namely, either there is no need to adapt, or, as exemplified by the Skylab 3 pilot, adaptation to weightlessness is achieved. Findings in some of the astronauts emphasize the distinction between two categories of vestibular side effects: immediate reflex phenomena (illusions, sensations of turning, etc.), and delayed epiphenomena that include the constellation of symptoms and syndromes comprising motion sickness. The drug combinations 1-scopolamine and d-amphetamine and promethazine hydrochloride and ephedrine sulfate are effective in prevention and treatment of motion sickness. It is concluded that prevention of motion sickness in any stressful motion environment involves selection, adaptation, and the use of drugs.

  2. Complications of microsurgery of vestibular schwannoma

    Betka, J.; Zvěřina, E.; Balogová, Zuzana; Profant, Oliver; Skřivan, J.; Kraus, J.; Lisý, J.; Syka, Josef; Chovanec, M.

    2014-01-01

    Roč. 2014, May 28 (2014), s. 315952. ISSN 2314-6133 R&D Projects: GA MZd NT12459 Grant ostatní: GA MZd(CZ) NT11543; GA MŠk(CZ) UNCE 204013; GA UK(CZ) SVV 266513; GA MŠk(CZ) Prvouk-P27/LF1/1 Institutional support: RVO:68378041 Keywords : acoustic neurona surgery * tumor surgery * vestibular schwannomas Subject RIV: FF - HEENT, Dentistry Impact factor: 1.579, year: 2014

  3. Repeat Gamma Knife surgery for vestibular schwannomas

    Sarah Lonneville; Carine Delbrouck; Cécile Renier; Daniel Devriendt; Nicolas Massager

    2015-01-01

    Background: Gamma Knife (GK) surgery is a recognized treatment option for the management of small to medium-sized vestibular schwannoma (VS) associated with high-tumor control and low morbidity. When a radiosurgical treatment fails to stop tumor growth, repeat GK surgery can be proposed in selected cases. Methods : A series of 27 GK retreatments was performed in 25 patients with VS; 2 patients underwent three procedures. The median time interval between GK treatments was 45 months. The me...

  4. Vestibular Facilitation of Optic Flow Parsing

    MacNeilage, Paul R.; Zhou Zhang; DeAngelis, Gregory C.; Angelaki, Dora E.

    2012-01-01

    Simultaneous object motion and self-motion give rise to complex patterns of retinal image motion. In order to estimate object motion accurately, the brain must parse this complex retinal motion into self-motion and object motion components. Although this computational problem can be solved, in principle, through purely visual mechanisms, extra-retinal information that arises from the vestibular system during self-motion may also play an important role. Here we investigate whether combining ve...

  5. Vestibular evoked myogenic potentials: an overview Potencial evocado miogênico vestibular: uma visão geral

    Renato Cal; Fayez Bahmad Jr.

    2009-01-01

    The vestibular evoked myogenic potential (VEMP) test is a relatively new diagnostic tool that is in the process of being investigated in patients with specific vestibular disorders. Briefly, the VEMP is a biphasic response elicited by loud clicks or tone bursts recorded from the tonically contracted sternocleidomastoid muscle, being the only resource available to assess the function of the saccule and the lower portion of the vestibular nerve. AIM: In this review, we shall highlight the histo...

  6. How the vestibular system interacts with somatosensory perception: A sham-controlled study with galvanic vestibular stimulation

    Ferre E.R.; Day B.L.; Bottini G.; Haggard P.

    2013-01-01

    The vestibular system has widespread interactions with other sensory modalities. Here we investigate whether vestibular stimulation modulates somatosensory function, by assessing the ability to detect faint tactile stimuli to the fingertips of the left and right hand with or without galvanic vestibular stimulation (GVS). We found that left anodal and right cathodal GVS, significantly enhanced sensitivity to mild shocks on either hand, without affecting response bias. There was no such effect ...

  7. Galvanic vestibular stimulation: a novel modulatory countermeasure for vestibular-associated movement disorders.

    Rizzo-Sierra, Carlos V; Gonzalez-Castaño, Alexander; Leon-Sarmiento, Fidias E

    2014-01-01

    Motion sickness or kinetosis is the result of the abnormal neural output originated by visual, proprioceptive and vestibular mismatch, which reverses once the dysfunctional sensory information becomes coherent. The space adaptation syndrome or space sickness relates to motion sickness; it is considered to be due to yaw, pith, and roll coordinates mismatch. Several behavioural and pharmacological measures have been proposed to control these vestibular-associated movement disorders with no success. Galvanic vestibular stimulation has the potential of up-regulating disturbed sensory-motor mismatch originated by kinetosis and space sickness by modulating the GABA-related ion channels neural transmission in the inner ear. It improves the signal-to-noise ratio of the afferent proprioceptive volleys, which would ultimately modulate the motor output restoring the disordered gait, balance and human locomotion due to kinetosis, as well as the spatial disorientation generated by gravity transition. PMID:24637984

  8. Galvanic vestibular stimulation: a novel modulatory countermeasure for vestibular-associated movement disorders

    Carlos V. Rizzo-Sierra

    2014-01-01

    Full Text Available Motion sickness or kinetosis is the result of the abnormal neural output originated by visual, proprioceptive and vestibular mismatch, which reverses once the dysfunctional sensory information becomes coherent. The space adaptation syndrome or space sickness relates to motion sickness; it is considered to be due to yaw, pith, and roll coordinates mismatch. Several behavioural and pharmacological measures have been proposed to control these vestibular-associated movement disorders with no success. Galvanic vestibular stimulation has the potential of up-regulating disturbed sensory-motor mismatch originated by kinetosis and space sickness by modulating the GABA-related ion channels neural transmission in the inner ear. It improves the signal-to-noise ratio of the afferent proprioceptive volleys, which would ultimately modulate the motor output restoring the disordered gait, balance and human locomotion due to kinetosis, as well as the spatial disorientation generated by gravity transition.

  9. The vestibular system does not modulate fusimotor drive to muscle spindles in relaxed leg muscles of subjects in a near-vertical position.

    Knellwolf, T P; Hammam, E; Macefield, V G

    2016-05-01

    It has been shown that sinusoidal galvanic vestibular stimulation (sGVS) has no effect on the firing of spontaneously active muscle spindles in either relaxed or voluntarily contracting human leg muscles. However, all previous studies have been conducted on subjects in a seated position. Given that independent vestibular control of muscle spindle firing would be more valuable during postural threat, we tested the hypothesis that this modulation would become apparent for subjects in a near-vertical position. Unitary recordings were made from 18 muscle spindle afferents via tungsten microelectrodes inserted percutaneously into the common peroneal nerve of awake human subjects laying supine on a motorized tilt table. All recorded spindle afferents were spontaneously active at rest, and each increased its firing rate during a weak static contraction. Sinusoidal bipolar binaural galvanic vestibular stimulation (±2 mA, 100 cycles) was applied to the mastoid processes at 0.8 Hz. This continuous stimulation produced a sustained illusion of "rocking in a boat" or "swinging in a hammock." The subject was then moved into a near-vertical position (75°), and the stimulation repeated. Despite robust vestibular illusions, none of the fusimotor-driven spindles exhibited phase-locked modulation of firing during sinusoidal GVS in either position. We conclude that this dynamic vestibular stimulus was insufficient to modulate the firing of fusimotor neurons in the near-vertical position. However, this does not mean that the vestibular system cannot modulate the sensitivity of muscle spindles via fusimotor neurons in free unsupported standing, when reliance on proprioceptive feedback is higher. PMID:26936989

  10. Imaging Finding in 222 Patients with Vestibular

    A. Zahiri

    2008-01-01

    Full Text Available Background/Objective: Vestibular Schwannoma is the most common cranial schwannoma with gradually produce sensorineural deafness. In this study we observed the effect of Gamma Knife therapy for control of this type of schwannoma."nPatients and Methods: We observed imaging findings of 250 patients with vestibular schwannoma from September 2003 to October 2007. We performed the Gamma Knife with C model (Elekta Company for the treatment and control of the tumor."nResults: The minimum age of our patients was 14 years and maximum age was 90 years. Twenty six patients was N.F.2, and female to male ratio was 2/1. The most common imaging finding was loss of central contrast enhancement in contrast MRI beginning after nine months after Gamma Knife. Loss of volume and cystic changes were other imaging findings and regrowth of tumor was seen in same case. After three years follow up, tumor control, tumor regression, and tumor enlargement were seen in 85%, 10%, and 5% of our patients respectively."nConclusion: Gamma Knife should be considered as a suitable treatment option for the treatment of Vestibular Schwannoma.

  11. Disrupting Vestibular Activity Disrupts Body Ownership.

    Hoover, Adria E N; Harris, Laurence R

    2015-01-01

    People are more sensitive at detecting asynchrony between a self-generated movement and visual feedback concerning that movement when the movement is viewed from a first-person perspective. We call this the 'self-advantage' and interpret it as an objective measure of self. Here we ask if disruption of the vestibular system in healthy individuals affects the self-advantage. Participants performed finger movements while viewing their hand in a first-person ('self') or third-person ('other') perspective and indicated which of two periods (one with minimum delay and the other with an added delay of 33-264 ms) was delayed. Their sensitivity to the delay was calculated from the psychometric functions obtained. During the testing, disruptive galvanic vestibular stimulation (GVS) was applied in five-minute blocks interleaved with five minutes of no stimulation for a total of 40 min. We confirmed the self-advantage under no stimulation (31 ms). In the presence of disruptive GVS this advantage disappeared and there was no longer a difference in performance between perspectives. The threshold delay for the 'other' perspective was not affected by the GVS. These results suggest that an intact vestibular signal is required to distinguish 'self' from 'other' and to maintain a sense of body ownership. PMID:26595957

  12. MRI in a quiescent vestibular schwannoma

    Vestibular schwannomas are benign neoplasms that take origin from Schwann cells, the majority arise from the vestibular branch of VIII cranial nerve. Unilateral sensorineural hearing loss is the most common symptom referred by patients who suffer this disease. With the advent and increasing use of MRI the diagnosis of this intra labyrinthine tumor has become more frequent. Paramagnetic contrast gadolinium has precise indication in the study protocol of this pathology. The high sensitivity of this method allows an early diagnosis. In patients with low auditory loss an excision of intra labyrinthine small tumors can offer a better therapeutic chance. We report a case of a 25 years old woman with progressive hearing loss. MRI with gadolinium enhancement demonstrated an intra vestibular schwannoma. In a follow-up control after 5 years MRI revealed no significant changes in tumor size or signal intensity. 3-D volumetric reconstruction offered complimentary information about this 'quiescent' schwannoma. Considering the tumoral behavior (without growth within five years) and the degree of hearing loss no invasive therapy was performed. (author)

  13. Can Electrical Vestibular Noise Be Used for the Treatment of Brain Diseases?

    Yamamoto, Yoshiharu; Soma, Rika; Struzik, Zbigniew R.; Kwak, Shin

    2005-11-01

    The therapy currently available for the treatment of degenerative neurological diseases is far from satisfactory, and a novel therapeutic strategy, especially for pharmacologically unresponsive patients, would be welcomed. The vestibular nerves are known to influence neuronal circuits in the medullary cardiovascular areas and, through the cerebellar vermis, the basal ganglia and the limbic system. By means of noisy galvanic vestibular stimulation (GVS), it may now be possible to ameliorate blunted responsiveness of degenerated neuronal circuits in the brains of multiple system atrophy (MSA) and/or Parkinson's disease (PD) patients, through a mechanism known as stochastic resonance. We evaluate the effect of 24-hour noisy GVS on long-term heart rate dynamics in seven MSA patients, and on daytime locomotor activity dynamics in twelve patients with either PD or levodopa unresponsive parkinsonism. Short-range heart rate variability and long-range anti-correlation of trunk activity are significantly increased by the noisy GVS compared with sham stimulation, suggestive of improved autonomic and motor responsiveness. The noisy GVS is effective in boosting the neuro-degenerative brains of MSA and/or PD patients, including those unresponsive to standard levodopa therapy.

  14. Head movements evoked in alert rhesus monkey by vestibular prosthesis stimulation: implications for postural and gaze stabilization.

    Diana E Mitchell

    Full Text Available The vestibular system detects motion of the head in space and in turn generates reflexes that are vital for our daily activities. The eye movements produced by the vestibulo-ocular reflex (VOR play an essential role in stabilizing the visual axis (gaze, while vestibulo-spinal reflexes ensure the maintenance of head and body posture. The neuronal pathways from the vestibular periphery to the cervical spinal cord potentially serve a dual role, since they function to stabilize the head relative to inertial space and could thus contribute to gaze (eye-in-head + head-in-space and posture stabilization. To date, however, the functional significance of vestibular-neck pathways in alert primates remains a matter of debate. Here we used a vestibular prosthesis to 1 quantify vestibularly-driven head movements in primates, and 2 assess whether these evoked head movements make a significant contribution to gaze as well as postural stabilization. We stimulated electrodes implanted in the horizontal semicircular canal of alert rhesus monkeys, and measured the head and eye movements evoked during a 100 ms time period for which the contribution of longer latency voluntary inputs to the neck would be minimal. Our results show that prosthetic stimulation evoked significant head movements with latencies consistent with known vestibulo-spinal pathways. Furthermore, while the evoked head movements were substantially smaller than the coincidently evoked eye movements, they made a significant contribution to gaze stabilization, complementing the VOR to ensure that the appropriate gaze response is achieved. We speculate that analogous compensatory head movements will be evoked when implanted prosthetic devices are transitioned to human patients.

  15. A study of whirlin isoforms in the mouse vestibular system suggests potential vestibular dysfunction in DFNB31-deficient patients.

    Mathur, Pranav Dinesh; Vijayakumar, Sarath; Vashist, Deepti; Jones, Sherri M; Jones, Timothy A; Yang, Jun

    2015-12-15

    The DFNB31 gene plays an indispensable role in the cochlea and retina. Mutations in this gene disrupt its various isoforms and lead to non-syndromic deafness, blindness and deaf-blindness. However, the known expression of Dfnb31, the mouse ortholog of DFNB31, in vestibular organs and the potential vestibular-deficient phenotype observed in one Dfnb31 mutant mouse (Dfnb31(wi/wi)) suggest that DFNB31 may also be important for vestibular function. In this study, we find that full-length (FL-) and C-terminal (C-) whirlin isoforms are expressed in the vestibular organs, where their stereociliary localizations are similar to those of developing cochlear inner hair cells. No whirlin is detected in Dfnb31(wi/wi) vestibular organs, while only C-whirlin is expressed in Dfnb31(neo/neo) vestibular organs. Both FL- and C-whirlin isoforms are required for normal vestibular stereociliary growth, although they may play slightly different roles in the central and peripheral zones of the crista ampullaris. Vestibular sensory-evoked potentials demonstrate severe to profound vestibular deficits in Dfnb31(neo/neo) and Dfnb31(wi/wi) mice. Swimming and rotarod tests demonstrate that the two Dfnb31 mutants have balance problems, with Dfnb31(wi/wi) mice being more affected than Dfnb31(neo/neo) mice. Because Dfnb31(wi/wi) and Dfnb31(neo/neo) mice faithfully recapitulate hearing and vision symptoms in patients, our findings of vestibular dysfunction in these Dfnb31 mutants raise the question of whether DFNB31-deficient patients may acquire vestibular as well as hearing and vision loss. PMID:26420843

  16. Vestibular papillomatosis: An important differential diagnosis of vulvar papillomas.

    Ozkur, Ezgi; Falay, Tugba; Turgut Erdemir, Asli Vefa; Gurel, Mehmet Salih; Leblebici, Cem

    2016-01-01

    Most authors believe that vestibular papillomatosis (VP) is an anatomical variant of the vestibular mucosa. But VP is sometimes misdiagnosed as genital warts and this can lead to aggressive investigations, therapy, and anxiety in patients. We present a patient with VP. Dermoscopy and reflectance confocal microscopy (RCM) were performed to differentiate VP from other papilomatous diseases of the vulva. PMID:27136629

  17. Vestibular influences on autonomic cardiovascular control in humans

    Biaggioni, I.; Costa, F.; Kaufmann, H.; Robertson, D. (Principal Investigator)

    1998-01-01

    There is substantial evidence that anatomical connections exist between vestibular and autonomic nuclei. Animal studies have shown functional interactions between the vestibular and autonomic systems. The nature of these interactions, however, is complex and has not been fully defined. Vestibular stimulation has been consistently found to reduce blood pressure in animals. Given the potential interaction between vestibular and autonomic pathways this finding could be explained by a reduction in sympathetic activity. However, rather than sympathetic inhibition, vestibular stimulation has consistently been shown to increase sympathetic outflow in cardiac and splanchnic vascular beds in most experimental models. Several clinical observations suggest that a link between vestibular and autonomic systems may also exist in humans. However, direct evidence for vestibular/autonomic interactions in humans is sparse. Motion sickness has been found to induce forearm vasodilation and reduce baroreflex gain, and head down neck flexion induces transient forearm and calf vasoconstriction. On the other hand, studies using optokinetic stimulation have found either very small, variable, or inconsistent changes in heart rate and blood pressure, despite substantial symptoms of motion sickness. Furthermore, caloric stimulation severe enough to produce nystagmus, dizziness, and nausea had no effect on sympathetic nerve activity measured directly with microneurography. No effect was observed on heart rate, blood pressure, or plasma norepinephrine. Several factors may explain the apparent discordance of these results, but more research is needed before we can define the potential importance of vestibular input to cardiovascular regulation and orthostatic tolerance in humans.

  18. Facial myokymia as a presenting symptom of vestibular schwannoma.

    Joseph B

    2002-07-01

    Full Text Available Facial myokymia is a rare presenting feature of a vestibular schwannoma. We present a 48 year old woman with a large right vestibular schwannoma, who presented with facial myokymia. It is postulated that facial myokymia might be due to a defect in the motor axons of the 7th nerve or due to brain stem compression by the tumor.

  19. Long-term hearing preservation in vestibular schwannoma

    Stangerup, Sven-Eric; Thomsen, Jens; Tos, Mirko;

    2010-01-01

    The aim of the present study was to evaluate the long-term hearing during "wait and scan" management of vestibular schwannomas.......The aim of the present study was to evaluate the long-term hearing during "wait and scan" management of vestibular schwannomas....

  20. Electronystagmographic analysis of caloric test parameters in vestibular disorders.

    Szirmai, Agnes; Keller, Balázs

    2013-01-01

    The electronystagmographical analysis of the eye movements provoked by caloric stimulation is an important method in the evaluation and topical diagnostic procedure of several vestibular lesions. The aim of the study was to compare the electronystagmographical results of caloric response in several vestibular disorders. The patients were divided into five groups: right and left unilateral and bilateral peripheral lesions, central vestibular dysfunction, and normal vestibular function. In the normal vestibular system group the average caloric nystagmus SPV in normal vestibular system was 17.4 °/s. In the peripheral lesion groups the average slow phase velocities are decreased in the affected side, as we expected. In the compensated vestibular lesion the average ASPV of caloric nystagmus is also decreased on the unaffected side. This might be caused by the effect of the central adaptive mechanisms. According to our observations, in central dysfunctions the average caloric ASPV and the spontaneous nystagmus ASPV is increased (25.0 °/s). This suggests that in central vestibular lesions the central inhibiting mechanisms of the caloric response are impaired. Our results show that electronystagmographical analysis of spontaneous and caloric nystagmus is very important in the evaluation of dizzy patients. PMID:22298250

  1. Plasticity of histamine H3 receptor expression and binding in the vestibular nuclei after labyrinthectomy in rat

    Karlstedt Kaj

    2004-09-01

    Full Text Available Abstract Background In rat, deafferentation of one labyrinth (unilateral labyrinthectomy results in a characteristic syndrome of ocular and motor postural disorders (e.g., barrel rotation, circling behavior, and spontaneous nystagmus. Behavioral recovery (e.g., diminished symptoms, encompassing 1 week after unilateral labyrinthectomy, has been termed vestibular compensation. Evidence suggesting that the histamine H3 receptor plays a key role in vestibular compensation comes from studies indicating that betahistine, a histamine-like drug that acts as both a partial histamine H1 receptor agonist and an H3 receptor antagonist, can accelerate the process of vestibular compensation. Results Expression levels for histamine H3 receptor (total as well as three isoforms which display variable lengths of the third intracellular loop of the receptor were analyzed using in situ hybridization on brain sections containing the rat medial vestibular nucleus after unilateral labyrinthectomy. We compared these expression levels to H3 receptor binding densities. Total H3 receptor mRNA levels (detected by oligo probe H3X as well as mRNA levels of the three receptor isoforms studied (detected by oligo probes H3A, H3B, and H3C showed a pattern of increase, which was bilaterally significant at 24 h post-lesion for both H3X and H3C, followed by significant bilateral decreases in medial vestibular nuclei occurring 48 h (H3X and H3B and 1 week post-lesion (H3A, H3B, and H3C. Expression levels of H3B was an exception to the forementioned pattern with significant decreases already detected at 24 h post-lesion. Coinciding with the decreasing trends in H3 receptor mRNA levels was an observed increase in H3 receptor binding densities occurring in the ipsilateral medial vestibular nuclei 48 h post-lesion. Conclusion Progressive recovery of the resting discharge of the deafferentated medial vestibular nuclei neurons results in functional restoration of the static postural and

  2. Vestibular schwannoma with contralateral facial pain – case report

    Ghodsi Mohammad

    2003-03-01

    Full Text Available Abstract Background Vestibular schwannoma (acoustic neuroma most commonly presents with ipsilateral disturbances of acoustic, vestibular, trigeminal and facial nerves. Presentation of vestibular schwannoma with contralateral facial pain is quite uncommon. Case presentation Among 156 cases of operated vestibular schwannoma, we found one case with unusual presentation of contralateral hemifacial pain. Conclusion The presentation of contralateral facial pain in the vestibular schwannoma is rare. It seems that displacement and distortion of the brainstem and compression of the contralateral trigeminal nerve in Meckel's cave by the large mass lesion may lead to this atypical presentation. The best practice in these patients is removal of the tumour, although persistent contralateral pain after operation has been reported.

  3. Vestibular disorders following different types of head and neck trauma

    Kolev, Ognyan I.; Sergeeva, Michaela

    2016-01-01

    Summary This review focuses on the published literature on vestibular disorders following different types of head and neck trauma. Current knowledge of the different causes and underlying mechanisms of vestibular disorders, as well as the sites of organic damage, is presented. Non-organic mechanisms are also surveyed. The frequency of occurrence of vestibular symptoms, and of other accompanying subjective complaints, associated with different types of trauma is presented and related to the specific causes. Hypotheses about the pathogenesis of traumatic vestibular disorders are presented, and the knowledge derived from animal experiments is also discussed. We believe this to be a very important topic, since vestibular complaints in traumatic patients often remain undiagnosed or underestimated in clinical practice. This review article aims to suggest directions for additional research and to provide guidance to both the scientific and clinical practice communities. PMID:27358219

  4. Analysis of signal processing in vestibular circuits with a novel light-emitting diodes-based fluorescence microscope.

    Direnberger, Stephan; Banchi, Roberto; Brosel, Sonja; Seebacher, Christian; Laimgruber, Stefan; Uhl, Rainer; Felmy, Felix; Straka, Hans; Kunz, Lars

    2015-05-01

    Optical visualization of neural network activity is limited by imaging system-dependent technical tradeoffs. To overcome these constraints, we have developed a powerful low-cost and flexible imaging system with high spectral variability and unique spatio-temporal precision for simultaneous optical recording and manipulation of neural activity of large cell groups. The system comprises eight high-power light-emitting diodes, a camera with a large metal-oxide-semiconductor sensor and a high numerical aperture water-dipping objective. It allows fast and precise control of excitation and simultaneous low noise imaging at high resolution. Adjustable apertures generated two independent areas of variable size and position for simultaneous optical activation and image capture. The experimental applicability of this system was explored in semi-isolated preparations of larval axolotl (Ambystoma mexicanum) with intact inner ear organs and central nervous circuits. Cyclic galvanic stimulation of semicircular canals together with glutamate- and γ-aminobutyric acid (GABA)-uncaging caused a corresponding modulation of Ca(2+) transients in central vestibular neurons. These experiments revealed specific cellular properties as well as synaptic interactions between excitatory and inhibitory inputs, responsible for spatio-temporal-specific sensory signal processing. Location-specific GABA-uncaging revealed a potent inhibitory shunt of vestibular nerve afferent input in the predominating population of tonic vestibular neurons, indicating a considerable impact of local and commissural inhibitory circuits on the processing of head/body motion-related signals. The discovery of these previously unknown properties of vestibular computations demonstrates the merits of our novel microscope system for experimental applications in the field of neurobiology. PMID:25847143

  5. Neural Network Model of Vestibular Nuclei Reaction to Onset of Vestibular Prosthetic Stimulation

    DiGiovanna, Jack; Nguyen, T. A. K.; Guinand, Nils; Pérez-Fornos, Angelica; Micera, Silvestro

    2016-01-01

    The vestibular system incorporates multiple sensory pathways to provide crucial information about head and body motion. Damage to the semicircular canals, the peripheral vestibular organs that sense rotational velocities of the head, can severely degrade the ability to perform activities of daily life. Vestibular prosthetics address this problem by using stimulating electrodes that can trigger primary vestibular afferents to modulate their firing rates, thus encoding head movement. These prostheses have been demonstrated chronically in multiple animal models and acutely tested in short-duration trials within the clinic in humans. However, mainly, due to limited opportunities to fully characterize stimulation parameters, there is a lack of understanding of “optimal” stimulation configurations for humans. Here, we model possible adaptive plasticity in the vestibular pathway. Specifically, this model highlights the influence of adaptation of synaptic strengths and offsets in the vestibular nuclei to compensate for the initial activation of the prosthetic. By changing the synaptic strengths, the model is able to replicate the clinical observation that erroneous eye movements are attenuated within 30 minutes without any change to the prosthetic stimulation rate. Although our model was only built to match this time point, we further examined how it affected subsequent pulse rate modulation (PRM) and pulse amplitude modulation (PAM). PAM was more effective than PRM for nearly all stimulation configurations during these acute tests. Two non-intuitive relationships highlighted by our model explain this performance discrepancy. Specifically, the attenuation of synaptic strengths for afferents stimulated during baseline adaptation and the discontinuity between baseline and residual firing rates both disproportionally boost PAM. Comodulation of pulse rate and amplitude has been experimentally shown to induce both excitatory and inhibitory eye movements even at high

  6. Experiment M-131 - Human vestibular function.

    Miller, E. F., II; Graybiel, A.

    1973-01-01

    The purpose of the M-131 experiment is to measure responses in astronauts throughout orbital flight that reflect vestibular function and compare them with measurements made before and after flight. Three subtasks require measurement of (1) susceptibility to motion sickness, (2) thresholds of response to stimulation of the semicircular canals, and (3) space perception, viz, visual and nonvisual localization, using external spacecraft and internal morphological frames of reference. Four astronauts will be available for all measurements in Skylab 2 and 3 and two additional astronauts for only the 'static' measurements during the flights.

  7. Human Vestibular Function - Skylab Experiment M131

    1972-01-01

    This set of photographs details Skylab's Human Vestibular Function experiment (M131). This experiment was a set of medical studies designed to determine the effect of long-duration space missions on astronauts' coordination abilities. This experiment tested the astronauts susceptibility to motion sickness in the Skylab environment, acquired data fundamental to an understanding of the functions of human gravity reception under prolonged absence of gravity, and tested for changes in the sensitivity of the semicircular canals. Data from this experiment was collected before, during, and after flight. The Marshall Space Flight Center had program management responsibility for the development of Skylab hardware and experiments.

  8. Reabilitação vestibular na criança: estudo preliminar Vestibular rehabilitation in children: preliminary study

    Roseli S. M. Bittar

    2002-08-01

    Full Text Available Forma de estudo: Clínico prospectivo. Objetivo: O estudo analisa prospectivamente os resultados da Reabilitação Vestibular pelo método de Cawtorne & Cooksey em 22 crianças, portadoras de vestibulopatia periférica, associada ou não a sintomas centrais, com idade média de 8,6 anos. Material e método: Os exames quantitativos da função vestibular utilizados para quantificar a vestibulopatia foram a eletronistagmografia e a prova rotatória pendular decrescente (PRPD, mas a história clínica altamente sugestiva de processo vestibular foi considerada diagnóstica mesmo na presença de exames normais. Resultado: Os resultados apontam a Reabilitação Vestibular como uma opção válida no tratamento das vestibulopatias na infância, uma vez que não houve casos não responsivos ao tratamento.Study design: Clinical prospective. Aim: The authors analyze prospectively 22 children (mean age 8,6 years with vestibulopathy treated with Vestibular Rehabilitation in order to verify its results. Material and methody: Twenty two children with peripheral vestibular disorders associated or not to central symptoms were submitted to vestibular stimulation by the method of Cawthorne & Cooksey. The methods used to quantify the vestibular abnormalities were the electronystagmography and rotational chair testing, but a suggestive history of vestibular disorder was accepted even the exams were normal. Results: All the patients improved and our results suggest that VR is a therapeutic alternative for the treatment of vestibular disorders in the children.

  9. Influence of galvanic vestibular stimulation on egocentric and object-based mental transformations

    Lenggenhager, Bigna; Lopez, Christophe; Blanke, Olaf

    2008-01-01

    The vestibular system analyses angular and linear accelerations of the head that are important information for perceiving the location of one's own body in space. Vestibular stimulation and in particular galvanic vestibular stimulation (GVS) that allow a systematic modification of vestibular signals has so far mainly been used to investigate vestibular influence on sensori-motor integration in eye movements and postural control. Comparatively, only a few behavioural and imaging studies have i...

  10. The human vestibular cortex revealed by coordinate-based activation likelihood estimation meta-analysis

    Lopez, C.; O. Blanke; Mast, F. W.

    2012-01-01

    The vestibular system contributes to the control of posture and eye movements and is also involved in various cognitive functions including spatial navigation and memory. These functions are subtended by projections to a vestibular cortex, whose exact location in the human brain is still a matter of debate (Lopez and Blanke, 2011). The vestibular cortex can be defined as the network of all cortical areas receiving inputs from the vestibular system, including areas where vestibular signals inf...

  11. Identification of Neural Networks That Contribute to Motion Sickness through Principal Components Analysis of Fos Labeling Induced by Galvanic Vestibular Stimulation

    Balaban, Carey D.; Sarah W Ogburn; Warshafsky, Susan G.; Abdul Ahmed; Bill J Yates

    2014-01-01

    Motion sickness is a complex condition that includes both overt signs (e.g., vomiting) and more covert symptoms (e.g., anxiety and foreboding). The neural pathways that mediate these signs and symptoms are yet to identified. This study mapped the distribution of c-fos protein (Fos)-like immunoreactivity elicited during a galvanic vestibular stimulation paradigm that is known to induce motion sickness in felines. A principal components analysis was used to identify networks of neurons activate...

  12. Passive motion reduces vestibular balance and perceptual responses.

    Fitzpatrick, Richard C; Watson, Shaun R D

    2015-05-15

    With the hypothesis that vestibular sensitivity is regulated to deal with a range of environmental motion conditions, we explored the effects of passive whole-body motion on vestibular perceptual and balance responses. In 10 subjects, vestibular responses were measured before and after a period of imposed passive motion. Vestibulospinal balance reflexes during standing evoked by galvanic vestibular stimulation (GVS) were measured as shear reaction forces. Perceptual tests measured thresholds for detecting angular motion, perceptions of suprathreshold rotation and perceptions of GVS-evoked illusory rotation. The imposed conditioning motion was 10 min of stochastic yaw rotation (0.5-2.5 Hz ≤ 300 deg s(-2) ) with subjects seated. This conditioning markedly reduced reflexive and perceptual responses. The medium latency galvanic reflex (300-350 ms) was halved in amplitude (48%; P = 0.011) but the short latency response was unaffected. Thresholds for detecting imposed rotation more than doubled (248%; P vestibular sensations of rotation evoked by GVS (mean 113 deg for 10 s at 1 mA) by 44% (P vestibular sensory autoregulation exists and that this probably involves central and peripheral mechanisms, possibly through vestibular efferent regulation. We propose that failure of these regulatory mechanisms at different levels could lead to disorders of movement perception and balance control during standing. PMID:25809702

  13. Biomimetic smart sensors for autonomous robotic behavior II: vestibular processing

    Xue, Shuwan; Deligeorges, Socrates; Soloway, Aaron; Lichtenstein, Lee; Gore, Tyler; Hubbard, Allyn

    2009-05-01

    Limited autonomous behaviors are fast becoming a critical capability in the field of robotics as robotic applications are used in more complicated and interactive environments. As additional sensory capabilities are added to robotic platforms, sensor fusion to enhance and facilitate autonomous behavior becomes increasingly important. Using biology as a model, the equivalent of a vestibular system needs to be created in order to orient the system within its environment and allow multi-modal sensor fusion. In mammals, the vestibular system plays a central role in physiological homeostasis and sensory information integration (Fuller et al, Neuroscience 129 (2004) 461-471). At the level of the Superior Colliculus in the brain, there is multimodal sensory integration across visual, auditory, somatosensory, and vestibular inputs (Wallace et al, J Neurophysiol 80 (1998) 1006-1010), with the vestibular component contributing a strong reference frame gating input. Using a simple model for the deep layers of the Superior Colliculus, an off-the-shelf 3-axis solid state gyroscope and accelerometer was used as the equivalent representation of the vestibular system. The acceleration and rotational measurements are used to determine the relationship between a local reference frame of a robotic platform (an iRobot Packbot®) and the inertial reference frame (the outside world), with the simulated vestibular input tightly coupled with the acoustic and optical inputs. Field testing of the robotic platform using acoustics to cue optical sensors coupled through a biomimetic vestibular model for "slew to cue" gunfire detection have shown great promise.

  14. Pattern of hair cell loss and delayed peripheral neuron degeneration in inner ear by a high-dose intratympanic gentamicin

    Jintao Yu; Dalian Ding; Fengjun Wang; Haiyan Jiang; Hong Sun; Richard Salvi

    2014-01-01

    To gain insights into the ototoxic effects of aminoglycoside antibiotics (AmAn) and delayed peripheral ganglion neuron death in the inner ear, experimental animal models were widely used with several different approaches including AmAn systemic injections, combination treat-ment of AmAn and diuretics, or local application of AmAn. In these approaches, systemic AmAn treatment alone usually causes incomplete damage to hair cells in the inner ear. Co-administration of diuretic and AmAn can completely destroy the cochlear hair cells, but it is impossible to damage the vestibular system. Only the approach of AmAn local application can selectively eliminate most sensory hair cells in the inner ear. Therefore, AmAn local application is more suitable for studies for complete hair cell destructions in cochlear and vestibular system and the following delayed peripheral ganglion neuron death. In current studies, guinea pigs were unilaterally treated with a high concentration of gentamicin (GM, 40 mg/ml) through the tympanic membrane into the middle ear cavity. Auditory functions and vestibular functions were measured before and after GM treatment. The loss of hair cells and delayed degeneration of ganglion neurons in both cochlear and vestibular system were quantified 30 days or 60 days after treatment. The results showed that both auditory and vestibular functions were completely abolished after GM treatment. The sensory hair cells were totally missing in the cochlea, and severely destroyed in vestibular end-organs. The delayed spiral ganglion neuron death 60 days after the deafening procedure was over 50%. However, no obvious pathological changes were observed in vestibular ganglion neurons 60 days post-treatment. These results indicated that a high concentration of gentamycin delivered to the middle ear cavity can destroy most sensory hair cells in the inner ear that subsequently causes the delayed spiral ganglion neuron degeneration. This model might be useful for studies

  15. Vestibular contributions to a right-hemisphere network for bodily awareness: combining galvanic vestibular stimulation and the "Rubber Hand Illusion".

    Ferrè, Elisa Raffaella; Berlot, Eva; Haggard, Patrick

    2015-03-01

    An altered sense of one's own body is a common consequence of vestibular damage, and also of damage to vestibular networks in the right hemisphere. However, few experimental studies have investigated whether vestibular signals contribute to bodily awareness. We addressed this issue by combining an established experimental model of bodily awareness (Rubber Hand Illusion -RHI) with galvanic vestibular stimulation (GVS) in healthy participants. Brief left anodal and right cathodal GVS (which predominantly activates vestibular networks in the right hemisphere), or right anodal and left cathodal GVS, or sham stimulation were delivered at random, while participants experienced either synchronous or asynchronous visuo-tactile stimulation of a rubber hand and their own hand. The drift in the perceived position of the participant's hand towards the rubber hand was used as a proxy measure of the resulting multisensory illusion of body ownership. GVS induced strong polarity-dependent effects on this measure of RHI: left anodal and right cathodal GVS produced significantly lower proprioceptive drift than right anodal and left cathodal GVS. We suggest that vestibular inputs influence the multisensory weighting functions that underlie bodily awareness: the right hemisphere vestibular projections activated by the left anodal and right cathodal GVS increased the weight of intrinsic proprioceptive signals about hand position, and decreased the weight of visual information responsible for visual capture during the RHI. PMID:25619847

  16. Growth factor treatment enhances vestibular hair cell renewal and results in improved vestibular function

    Kopke, Richard D; Jackson, Ronald L; Li, Geming; Rasmussen, Mark D.; Hoffer, Michael E.; Frenz, Dorothy A.; Costello, Michael; Schultheiss, Peter; Van De Water, Thomas R.

    2001-01-01

    The vestibules of adult guinea pigs were lesioned with gentamicin and then treated with perilymphatic infusion of either of two growth factor mixtures (i.e., GF I or GF II). GF I contained transforming growth factor α (TGFα), insulin-like growth factor type one (IGF-1), and retinoic acid (RA), whereas GF II contained those three factors and brain-derived neurotrophic factor. Treatment with GF I significantly enhanced vestibular hair cell renewal in ototoxin-damaged ...

  17. Reabilitação vestibular em um hospital universitário Vestibular rehabilitation in a university hospital

    Flávia da Silva Tavares; Maria Francisca Colella dos Santos; Keila Alessandra Baraldi Knobel

    2008-01-01

    A Reabilitação Vestibular visa melhorar o equilíbrio global, a qualidade de vida e orientação espacial dos pacientes com tontura. OBJETIVOS: Traçar o perfil dos pacientes atendidos no Ambulatório de Reabilitação Vestibular do Setor de Otoneurologia de um hospital universitário e verificar os resultados obtidos no período de novembro/2000 a dezembro/2004. MATERIAL E MÉTODO: Levantamento de dados contidos nas fichas dos 93 pacientes submetidos à Reabilitação Vestibular no período. FORMA DE ESTU...

  18. Improved results for vestibular schwannoma radiosurgery

    PURPOSE/OBJECTIVE: Treatment techniques in radiosurgery have changed since 1987. We reviewed patients who received radiosurgery for vestibular schwannoma to identify these changes and to investigate any differences in tumor control and complications. MATERIALS and METHODS: One hundred thirty-eight unilateral vestibular schwannoma patients with a minimum follow-up of two years after treatment with gamma knife radiosurgery between 1987 and 1992 were analyzed. The early treatment group consisted of 55 patients treated between 1987-1989 (median: tumor volume 3.63 cc, Dmin 18.1 Gy, Dmax 35.4 Gy, isocenters 2.3, follow-up 50.4 mos.). The later treatment group consisted of 83 patients treated between 1990-1992 (median: tumor volume 3.81 cc, Dmin 16.0 Gy, Dmax 31.6 Gy, isocenters 4.7, follow-up 35.8 mos.) RESULTS: Clinical tumor recurrence requiring surgical intervention occurred in one patient in each group. The overall actuarial clinical tumor control rate was 98%. Slight increases in tumor size (1 to 2 mm) were identified in five other patients not requiring intervention, because of no further tumor growth (n=4) or shrinkage (n=1). This led to an overall radiologic tumor control rate of 92% (not significantly different in either group). Compared to the early treatment group, the incidence of facial neuropathy (temporary or permanent) decreased in the later group (49% vs. 11%, p < 0.0001), as did trigeminal neuropathy (40% vs. 8%, p < 0.0001). Serviceable hearing preservation improved only slightly in the later group (27% vs. 40%, p = 0.70). CONCLUSION: We document a significant decrease in the morbidity of vestibular schwannoma radiosurgery over this time period with no decrease in the high rate of tumor control. This improvement is attributed to a) better conformal dose-planning with stereotactic MRI rather than CT, b) an increase in the number of isocenters used, and c) a reduction in the average dose administered by 2 Gy

  19. Ongoing cell death and immune influences on regeneration in the vestibular sensory organs

    Warchol, M. E.; Matsui, J. I.; Simkus, E. L.; Ogilive, J. M.

    2001-01-01

    Hair cells in the vestibular organs of birds have a relatively short life span. Mature hair cells appear to die spontaneously and are then quickly replaced by new hair cells that arise from the division of epithelial supporting cells. A similar regenerative mechanism also results in hair cell replacement after ototoxic damage. The cellular basis of hair cell turnover in the avian ear is not understood. We are investigating the signaling pathways that lead to hair cell death and the relationship between ongoing cell death and cell production. In addition, work from our lab and others has demonstrated that the avian inner ear contains a resident population of macrophages and that enhanced numbers of macrophages are recruited to sites of hair cells lesions. Those observations suggest that macrophages and their secretory products (cytokines) may be involved in hair cell regeneration. Consistent with that suggestion, we have found that treatment with the anti-inflammatory drug dexamethasone reduces regenerative cell proliferation in the avian ear, and that certain macrophage-secreted cytokines can influence the proliferation of vestibular supporting cells and the survival of statoacoustic neurons. Those results suggest a role for the immune system in the process of sensory regeneration in the inner ear.

  20. Behavioral Assessment of the Aging Mouse Vestibular System

    Tung, Victoria W. K.; Burton, Thomas J.; Dababneh, Edward; Quail, Stephanie L.; Camp, Aaron J.

    2014-01-01

    Age related decline in balance performance is associated with deteriorating muscle strength, motor coordination and vestibular function. While a number of studies show changes in balance phenotype with age in rodents, very few isolate the vestibular contribution to balance under either normal conditions or during senescence. We use two standard behavioral tests to characterize the balance performance of mice at defined age points over the lifespan: the rotarod test and the inclined balance beam test. Importantly though, a custom built rotator is also used to stimulate the vestibular system of mice (without inducing overt signs of motion sickness). These two tests have been used to show that changes in vestibular mediated-balance performance are present over the murine lifespan. Preliminary results show that both the rotarod test and the modified balance beam test can be used to identify changes in balance performance during aging as an alternative to more difficult and invasive techniques such as vestibulo-ocular (VOR) measurements. PMID:25045963

  1. Distinct spontaneous shrinkage of a sporadic vestibular schwannoma

    Huang, Xiaowen; Cayé-Thomasen, Per; Stangerup, Sven-Eric

    2013-01-01

    We present a case with outspoken spontaneous vestibular schwannoma shrinkage and review the related literature. The patient was initially diagnosed with a left-sided, intrameatal vestibular schwannoma, which subsequently grew into the cerebello-pontine angle (CPA), followed by total shrinkage...... of the CPA component without any intervention over a 12-year observation period. The literature on spontaneous tumor shrinkage was retrieved by searching the subject terms "vestibular schwannoma, conservative management" in PubMed/MEDLINE database, without a time limit. Of the published data, the articles...... on "shrinkage" or "negative growth" or "regression" or "involution" of the tumor were selected, and the contents on the rate, extent and mechanism of spontaneous tumor shrinkage were extracted and reviewed. The reported rate of spontaneous shrinkage of vestibular schwannoma is 5-10% of patients managed...

  2. Distinct spontaneous shrinkage of a sporadic vestibular schwannoma.

    Huang, Xiaowen; Caye-Thomasen, Per; Stangerup, Sven-Eric

    2013-04-01

    We present a case with outspoken spontaneous vestibular schwannoma shrinkage and review the related literature. The patient was initially diagnosed with a left-sided, intrameatal vestibular schwannoma, which subsequently grew into the cerebello-pontine angle (CPA), followed by total shrinkage of the CPA component without any intervention over a 12-year observation period. The literature on spontaneous tumor shrinkage was retrieved by searching the subject terms "vestibular schwannoma, conservative management" in PubMed/MEDLINE database, without a time limit. Of the published data, the articles on "shrinkage" or "negative growth" or "regression" or "involution" of the tumor were selected, and the contents on the rate, extent and mechanism of spontaneous tumor shrinkage were extracted and reviewed. The reported rate of spontaneous shrinkage of vestibular schwannoma is 5-10% of patients managed conservatively. Extreme shrinkage of the tumor may occur spontaneously. PMID:22858145

  3. Vestibular impairment in patients with Charcot-Marie-Tooth disease

    Poretti, A.; Palla, A; Tarnutzer, A A; Petersen, J A; Weber, K P; Straumann, D; Jung, H H

    2013-01-01

    OBJECTIVE: This case-control study aimed to determine whether the imbalance in Charcot-Marie-tooth (CMT) disease is caused only by reduced proprioceptive input or whether the involvement of the vestibular nerve is an additional factor. METHODS: Fifteen patients with CMT disease (aged 48 ± 17 years; 8 women) underwent cervical vestibular-evoked myogenic potentials, which reflect otolith-spinal reflex function, and quantitative horizontal search-coil head-impulse testing, which assesses the hi...

  4. Vestibular function in families with inherited autosomal dominant hearing loss

    Street, Valerie A.; Kallman, Jeremy C.; Strombom, Paul D.; Bramhall, Naomi F; Phillips, James O.

    2008-01-01

    The inner ear contains the developmentally related cochlea and peripheral vestibular labyrinth. Given the similar physiology between these two organs, hearing loss and vestibular dysfunction may be expected to occur simultaneously in individuals segregating mutations in inner ear genes. Twenty-two different genes have been discovered that when mutated lead to non-syndromic autosomal dominant hearing loss. A review of the literature indicates that families segregating mutations in 13 of these ...

  5. Galvanic Vestibular Stimulation in Hemi-Spatial Neglect

    David Wilkinson; Mohamed Sakel

    2014-01-01

    Hemi-spatial neglect is an attentional disorder in which the sufferer fails to acknowledge or respond to stimuli appearing in contralesional space. In recent years, it has become clear that a measurable reduction in contralesional neglect can occur during galvanic vestibular stimulation, a technique by which transmastoid, small amplitude current induces lateral, attentional shifts via asymmetric modulation of the left and right vestibular nerves. However, it remains unclear whether this reduc...

  6. Postural control adaptation during galvanic vestibular and vibratory proprioceptive stimulation.

    Fransson, Per-Anders; Hafström, Anna; Karlberg, Mikael; Magnusson, Måns; Tjäder, Annika; Johansson, Rolf

    2003-01-01

    he objective for this study was to investigate whether the adaptation of postural control was similar during galvanic vestibular stimulation and during vibratory proprioceptivestimulation of the calf muscles. Healthy subjects were tested during erect stance with eyes open or closed. An analysis method designed to consider the adaptive adjustments was used to evaluate the motion dynamics and the evoked changes of posture and stimulation response.Galvanic vestibular stimulation induced primaril...

  7. Using Galvanic Vestibular Stimulation to Sense Abstract Data

    MÀki-Reinikka, Kasperi; Torniainen, Jari; Alafuzoff, Aleksander; Kotkanen, Henri; Toivanen, Jukka M.

    2013-01-01

    We propose using galvanic vestibular stimulation for presenting abstract data, for instance stock market trends. Using galvanic vestibular stimulation, data is felt directly as a perturbation in the sense of balance. This work is showcased as an art performance, where stock market fluctuations cause a person to maintain or lose balance. We present the artistic and technical principles underlying the performance and describe the technical implementation of a working system. The work shows how ...

  8. Galvanic vestibular stimulation in hemi-spatial neglect

    Wilkinson, David; Zubko, Olga; Sakel, Mohamed; Coulton, Simon; Higgins, Tracy; Pullicino, Patrick

    2014-01-01

    Hemi-spatial neglect is an attentional disorder in which the sufferer fails to acknowledge or respond to stimuli appearing in contralesional space. In recent years, it has become clear that a measurable reduction in contralesional neglect can occur during galvanic vestibular stimulation, a technique by which transmastoid, small amplitude current induces lateral, attentional shifts via asymmetric modulation of the left and right vestibular nerves. However, it remains unclear whether this reduc...

  9. Morphological analysis of the vestibular aqueduct by computerized tomography images

    Objective: In the last two decades, advances in the computerized tomography (CT) field revise the internal and medium ear evaluation. Therefore, the aim of this study is to analyze the morphology and morphometric aspects of the vestibular aqueduct on the basis of computerized tomography images (CTI). Material and method: Computerized tomography images of vestibular aqueducts were acquired from patients (n = 110) with an age range of 1-92 years. Thereafter, from the vestibular aqueducts images a morphometric analysis was performed. Through a computerized image processing system, the vestibular aqueduct measurements comprised of its area, external opening, length and the distance from the vestibular aqueduct to the internal acoustic meatus. Results: The morphology of the vestibular aqueduct may be funnel-shaped, filiform or tubular and the respective proportions were found to be at 44%, 33% and 22% in children and 21.7%, 53.3% and 25% in adults. The morphometric data showed to be of 4.86 mm2 of area, 2.24 mm of the external opening, 4.73 mm of length and 11.88 mm of the distance from the vestibular aqueduct to the internal acoustic meatus, in children, and in adults it was of 4.93 mm2, 2.09 mm, 4.44 mm, and 11.35 mm, respectively. Conclusions: Computerized tomography showed that the vestibular aqueduct presents high morphological variability. The morphometric analysis showed that the differences found between groups of children and adults or between groups of both genders were not statistically significant

  10. Metachronous schwannoma in the colon with vestibular schwannoma

    Jung, Eun-Joo; Han, Hye Seung; Koh, Young-Cho; Cho, Joon; Ryu, Chun-Geun; Paik, Jin Hee; Hwang, Dae-Yong

    2014-01-01

    We experienced a case of vestibular schwannoma and metachronous schwannoma in the colon. A 59-year-old female presented with a 1-month history of hematochezia. She had undergone suboccipital craniectomy resulting in radical subtotal resection, followed by gamma knife radiosurgery for a large left vestibular schwannoma 4 years prior to admission. On preoperative colonoscopy, a huge mass through which the colonoscope could not be passed was detected. CT scans showed colo-colonic intussusception...