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1.
Otolaryngol Pol ; 76(4): 1-6, 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-36047324

RESUMO

<b>Introduction:</b> Migrainous vertigo (MV) is one of the most common causes of episodic vertigo. Diagnostic criteria for MV are described in the appendix to the third edition of the International Classification of Headache Disorders (Beta Version). The dysfunction exerts its impact on certain peripheral and central structures within the vestibular system. </br></br> <b>Aim:</b> The aim of the study was to assess the function of the central and peripheral vestibular system in patients with MV based on the results of objective clinical tests including videonystagmography (VNG) and cervical vestibular evoked myogenic potentials (cVEMP) depending on the duration of the disease. </br></br> <b>Material and methods:</b> A query of the medical records of patients receiving vertigo treatment at the Department of Otolaryngo-logy of the Centre of Postgraduate Medical Education over the last four years returned a total of 84 cases of patients diagnosed with MV; the patients were assigned to either of the following two groups: study group I (SG1) - 42 patients with MV in whom the symp-tom onset had occurred within one year prior to hospital admission, and study group II (SG2) - 42 patients who had been suffering from vertigo for about 10 years. </br></br> <b>Results:</b> Patients in both groups (SG1 and SG2) were diagnosed with all three types of vestibular dysfunction (central, peri-pheral and mixed), with peripheral vestibular dysfunction being the predominant finding. A thorough analysis of the dura-tion of vestibular attacks revealed that the patients suffering from MV for a longer period of time (SG2) suffered from vertigo attacks which were longer than those in the patients with the shorter lasting-disorder (SG1). The duration of vertigo episodes was also estimated to be prolonged in peripheral and mixed types of vestibular disorders. The percentage of individuals with peripheral and mixed vestibular disorders increased significantly with increasing MV episode durations.


Assuntos
Transtornos de Enxaqueca , Doenças Vestibulares , Potenciais Evocados Miogênicos Vestibulares , Vestíbulo do Labirinto , Humanos , Transtornos de Enxaqueca/complicações , Transtornos de Enxaqueca/diagnóstico , Vertigem/diagnóstico , Vertigem/etiologia , Potenciais Evocados Miogênicos Vestibulares/fisiologia
2.
Artigo em Chinês | MEDLINE | ID: mdl-36058659

RESUMO

Objective: To investigate the clinical features and prognosis in patients with idiopathic sudden sensorineural hearing loss (ISSNHL) with blood-labyrinth barrier breakdown (BLB-B). Methods: Clinical data of patients with unilateral ISSNHL hospitalized from December 2017 to December 2018 were retrospectively analyzed. According to the results of 3D-FLAIR MRI and enhanced MRI scanning, these patients were divided into two groups, i.e., normal and abnormal inner ear groups. The patients in abnormal inner ear group were further divided into two subgroups: BLB-B and BLB-B with exudation. The differences and correlations among the groups in clinical characteristics, in terms of gender, age, deafness side, basic diseases, dizziness/vertigo, vestibular function, hearing loss degree, as well as classification of hearing curve, and prognosis were analyzed by statistical software SPSS 23.0. Results: Data were collected from 150 cases, in which 68 were male and 82 were female, aged (46.2±14.6) years, including 67 cases with normal inner ears and 83 cases with abnormal inner ears (13 cases with BLB-B; 70 cases with BLB-B and exudation). The dizziness/vertigo incidence, side ratio, hearing loss degree, classification of hearing curve, vestibular dysfunction (vestibular double temperature test, HIT and VAT) and therapeutic effect were different between normal and abnormal inner ear groups (P<0.05). The dizziness/vertigo incidence, side ratio, hearing loss degree, classification of hearing curve, vestibular dysfunction (vestibular double temperature test, o/cVEMP, HIT and VAT) and therapeutic effect were different among normal inner ear, BLB-B and BLB-B with exudation groups (P<0.05). Pairwise comparison between groups revealed that vestibular dysfunction (vestibular double temperature test, o/cVEMP, HIT and VAT) and therapeutic effect were different between normal inner ear and BLB-B groups (P<0.05); The dizziness/vertigo incidence, side ratio, hearing loss degree, classification of hearing curve, vestibular dysfunction (vestibular double temperature test, o/cVEMP, HIT and VAT) and therapeutic effect were different between normal inner ear and BLB-B with exudation groups (P<0.05). There was no significant different between BLB-B and BLB-B with exudation groups. Conclusion: BLB-B displayed by 3D-FLAIR MRI manifestation in ISSNHL patients indicates more serious cochlear and vestibular dysfunction, and worse therapeutic effect.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Vestíbulo do Labirinto , Tontura , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Vertigem
3.
PLoS Biol ; 20(9): e3001798, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36103550

RESUMO

Sensory pathways provide complex and multifaceted information to the brain. Recent advances have created new opportunities for applying our understanding of the brain to sensory prothesis development. Yet complex sensor physiology, limited numbers of electrodes, and nonspecific stimulation have proven to be a challenge for many sensory systems. In contrast, the vestibular system is uniquely suited for prosthesis development. Its peripheral anatomy allows site-specific stimulation of 3 separate sensory organs that encode distinct directions of head motion. Accordingly, here, we investigated whether implementing natural encoding strategies improves vestibular prosthesis performance. The eye movements produced by the vestibulo-ocular reflex (VOR), which plays an essential role in maintaining visual stability, were measured to quantify performance. Overall, implementing the natural tuning dynamics of vestibular afferents produced more temporally accurate VOR eye movements. Exploration of the parameter space further revealed that more dynamic tunings were not beneficial due to saturation and unnatural phase advances. Trends were comparable for stimulation encoding virtual versus physical head rotations, with gains enhanced in the latter case. Finally, using computational methods, we found that the same simple model explained the eye movements evoked by sinusoidal and transient stimulation and that a stimulation efficacy substantially less than 100% could account for our results. Taken together, our results establish that prosthesis encodings that incorporate naturalistic afferent dynamics and account for activation efficacy are well suited for restoration of gaze stability. More generally, these results emphasize the benefits of leveraging the brain's endogenous coding strategies in prosthesis development to improve functional outcomes.


Assuntos
Membros Artificiais , Vestíbulo do Labirinto , Animais , Movimentos Oculares , Macaca mulatta , Reflexo Vestíbulo-Ocular/fisiologia , Vestíbulo do Labirinto/fisiologia
4.
Sci Rep ; 12(1): 15424, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36104440

RESUMO

Posture and gait are maintained by sensory inputs from the vestibular, visual, and somatosensory systems and motor outputs. Upon vestibular damage, the visual and/or somatosensory systems functionally substitute by cortical mechanisms called "sensory reweighting". We investigated the cerebrocortical mechanisms underlying sensory reweighting after unilateral labyrinthectomy (UL) in mice. Arc-dVenus transgenic mice, in which the gene encoding the fluorescent protein dVenus is transcribed under the control of the promoter of the immediate early gene Arc, were used in combination with whole-brain three-dimensional (3D) imaging. Performance on the rotarod was measured as a behavioral correlate of sensory reweighting. Following left UL, all mice showed the head roll-tilt until UL10, indicating the vestibular periphery damage. The rotarod performance worsened in the UL mice from UL1 to UL3, which rapidly recovered. Whole-brain 3D imaging revealed that the number of activated neurons in S1, but not in V1, in UL7 was higher than that in sham-treated mice. At UL7, medial prefrontal cortex (mPFC) and agranular insular cortex (AIC) activation was also observed. Therefore, sensory reweighting to the somatosensory system could compensate for vestibular dysfunction following UL; further, mPFC and AIC contribute to the integration of sensory and motor functions to restore balance.


Assuntos
Vestíbulo do Labirinto , Animais , Córtex Cerebral , Camundongos , Neurônios/fisiologia , Postura , Vestíbulo do Labirinto/fisiologia
5.
Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi ; 36(9): 651-658;664, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36036063

RESUMO

Auditory and vestibular function detection technology is the premise and key to the diagnosis and management for inner ear diseases. Concurrent damage to the auditory and vestibular system occurs in many inner ear diseases. The general points and issues on hearing and vestibular function tests, as well as the clinical significance of refined and individualized comprehensive evaluation of inner ear function are described in this paper.


Assuntos
Doenças do Labirinto , Vestíbulo do Labirinto , Audição , Humanos
6.
Artigo em Chinês | MEDLINE | ID: mdl-36036070

RESUMO

Objective:To complete the working principle design and prototype construction of the Chinese multichannel vestibular prosthesis (CMVP) with independent intellectual property rights, and verify its working performance, so as to lay the foundation for the clinical promotion and application of CMVP. Methods:On the basis of previous research, the working principle of CMVP was constructed based on the information encoding principle of vestibular nervous system, and the circuit was designed according to the principle. Then, appropriate electronic components and software systems were selected to construct a CMVP prototype according to the design. Finally, the input and output characteristics of the CMVP prototype were verified through the performance test. Results:In the present study, a block diagram of the working principle of the CMVP was successfully designed and drawn, and the working principle was explained in detail according to the block diagram. Further, the circuit diagram of the CMVP was designed and drawn based on the working principle, then the selected electronic components and software systems were combined one by one to complete the construction of a prototype. Finally, the performance test for the prototype was completed, which showed that all stimulus electrodes of the prototype could output biphasic pulse current, and the frequency of biphasic pulse current was modulated by the spatial rotation data input sensed by a motion sensor. Conclusion:The working principle and circuit design of the CMVP are reasonable; the CMVP prototype in China has been successfully constructed; the spatial rotation motion sensing input and the modulated pulse current output are stable and reliable.


Assuntos
Vestíbulo do Labirinto , China , Humanos , Próteses e Implantes , Rotação , Software
7.
Artigo em Chinês | MEDLINE | ID: mdl-36036073

RESUMO

Objective: To investigate the characteristics of air-conducted sound cervical vestibular evoked myogenic potential (ACS-cVEMP) and bone-conducted vibration cervical vestibular evoked myogenic potential (BCV-cVEMP) in healthy preschool children, and to provide the normal reference range of VEMP for preschool children in China. Methods:Forty-four normal-hearing children (88 ears) aged 3-7 years were recruited to undergo ACS-cVEMP and BCV-cVEMP determination. These children were divided into two groups according to age: 3-4 years old group ( 17 cases, 34 ears) and 5-7 years old group ( 27 cases, 54 ears). The response rates and waveform parameters were recorded and analyzed statistically using SPSS 18.0 software. Results:The response rates of ACS-cVEMP, BCV-cVEMP in 44 normal-hearing children (88 ears) were 96.59%(85/88) and 97.73%(86/88) respectively, and there was no significant difference between the two groups (P > 0.05). The response rates of ACS-cVEMP in 3-4 year old group and 5-7 year old group were 94.12% (32/34) and 98.15% (53/54) respectively, and there was no significant difference between the two groups(P>0.05); The response rates of BCV-cVEMP in 3-4 year old group and 5-7 year old group were 94.12% (32/34) and 100.00%(54/54) respectively, and there was no significant difference between the two groups (P>0.05). Compared with the 5-7 year old group, the latency of p1 and n1 in the 3-4 year old group was shorter (P<0.05) and the amplitude was higher (P<0.05), and there was no significant difference in other parameters (P>0.05). There was no statistical difference in threshold, n1, p1 latency, n1-p1 wave interval, n1-p1 amplitude, and amplitude asymmetry ratio of BCV-cVEMP between the two groups (P>0.05). Conclusion:ACS-cVEMP and BCV-cVEMP can be elicited in most preschool children, and cVEMP is a feasible method to detect vestibular function in children.


Assuntos
Potenciais Evocados Miogênicos Vestibulares , Vestíbulo do Labirinto , Condução Óssea , Criança , Pré-Escolar , Humanos , Som , Vibração
8.
Artigo em Chinês | MEDLINE | ID: mdl-35959574

RESUMO

Objective:To investigate the impact of time interval from symptoms onset to vestibular rehabilitation on the recovery of patients in the acute phase of vestibular neuritis. Methods:Thirty-one patients with vestibular neuritis treated in outpatient and inpatient settings from December 2019 to July 2021 were selected and randomly divided into vestibular rehabilitation group and general treatment group. The vestibular rehabilitation group was subdivided into early-intervention group (1-week after symptom onset) and late-intervention group (2-week after symptom onset) according to the interval from the onset to vestibular rehabilitation. The differences in DP, UW, VOR, DHI, BBS and SAS values at 1 month and 3 months after treatment were compared among early-intervention group(11 cases), late-intervention group (10 cases) and general treatment group(10 cases). Results:For patients in the vestibular rehabilitation group and the general treatment group, DP, UW, VOR gain, DHI score and SAS score were significantly different after treatment ( P<0.05) and no significant difference was found in BBS score (P>0.05 ). Pairwise comparisons between early-intervention and late-intervention group showed that the DP, UW and VOR gain were significantly different (P<0.05), while the score of DHI and SAS were not significantly different (P>0.05). Conclusion:Vestibular rehabilitation therapy can accelerate vestibular compensation, relieve vertigo symptoms and anxiety symptoms in patients with vestibular neuritis. It is better to be carried out within 1 week after symptom onset.


Assuntos
Neuronite Vestibular , Vestíbulo do Labirinto , Ansiedade , Tontura/diagnóstico , Humanos , Neuronite Vestibular/diagnóstico
9.
Expert Rev Neurother ; 22(8): 669-680, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35912850

RESUMO

INTRODUCTION: Vestibular rehabilitation (VR) is now a subject of active studies and has been shown to be effective for multiple vestibular disorders, peripheral or central. VR is a physical therapy that helps train the central nervous system to compensate for vestibular dysfunction. There is moderate to strong evidence that VR is safe and effective for the management of peripheral vestibular dysfunction. Nonetheless, the studies on how VR works on central vestibular dysfunction remains scanty. AREAS COVERED: This article addressed the rehabilitation strategies and possible mechanisms, including how central vestibular function might improve upon rehabilitation. In addition, it provides some examples concerning the effect of VR on central vestibular dysfunction. EXPERT OPINION: VR works on the vestibular system through repetition of specific physical exercises that activate central neuroplastic mechanisms to achieve adaptive compensation of the impaired functions. VR has become a mainstay in the management of patients with dizziness and balance dysfunction. Individualized VR programs are a safe and effective treatment option for a large percentage of patients with central vestibular disease reporting imbalance and dizziness. Exploration of various treatment strategies and possible mechanisms will help develop the best and personalized VR treatment for patients with central vestibular dysfunction.


Assuntos
Doenças Vestibulares , Vestíbulo do Labirinto , Tontura/reabilitação , Humanos , Equilíbrio Postural/fisiologia , Vertigem/reabilitação
10.
Otol Neurotol ; 43(8): e814-e819, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35970155

RESUMO

A "gold standard" for quantitatively diagnosing inner ear malformations (IEMs) and a consensus on normative measurements are lacking. Reference ranges and cutoff values of inner ear dimensions may add in distinguishing IEM types. This study evaluates the volumes of the cochlea and vestibular system in different types of IEM. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary academic center. PATIENTS: High-resolution CT scans of 115 temporal bones (70 with IEM; cochlear hypoplasia [CH]; n = 19), incomplete partition (IP) Types I and III (n = 16), IP Type II with an enlarged vestibular aqueduct (Mondini malformation; n = 16), enlarged vestibular aqueduct syndrome (n = 19), and 45 controls. INTERVENTIONS: Volumetry by software-based, semiautomatic segmentation, and 3D reconstruction. MAIN OUTCOME MEASURES: Differences in volumes among IEM and between IEM types and controls; interrater reliability. RESULTS: Compared with controls (mean volume, 78.0 mm3), only CH showed a significantly different cochlear volume (mean volume, 30.2 mm3; p < 0.0001) among all types of IEM. A cutoff value of 60 mm3 separated 100% of CH cases from controls. Compared with controls, significantly larger vestibular system volumes were found in Mondini malformation (mean difference, 22.9 mm3; p = 0.009) and IP (mean difference, 24.1 mm3; p = 0.005). In contrast, CH showed a significantly smaller vestibular system volume (mean difference, 41.1 mm3; p < 0.0001). A good interrater reliability was found for all three-dimensional measurements (ICC = 0.86-0.91). CONCLUSION: Quantitative reference values for IEM obtained in this study were in line with existing qualitative diagnostic characteristics. A cutoff value less than 60 mm3 may indicate an abnormally small cochlea. Normal reference values for volumes of the cochlea and vestibular system may aid in diagnosing IEM.


Assuntos
Implante Coclear , Perda Auditiva Neurossensorial , Aqueduto Vestibular , Vestíbulo do Labirinto , Cóclea/anormalidades , Cóclea/diagnóstico por imagem , Perda Auditiva Neurossensorial/diagnóstico por imagem , Humanos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Aqueduto Vestibular/anormalidades , Aqueduto Vestibular/diagnóstico por imagem , Vestíbulo do Labirinto/anormalidades , Vestíbulo do Labirinto/diagnóstico por imagem
11.
Nat Commun ; 13(1): 4699, 2022 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-35948549

RESUMO

Gaze stabilization compensates for movements of the head or external environment to minimize image blurring. Multisensory information stabilizes the scene on the retina via the vestibulo-ocular (VOR) and optokinetic (OKR) reflexes. While the organization of neuronal circuits underlying VOR is well-described across vertebrates, less is known about the contribution and evolution of the OKR and the basic structures allowing visuo-vestibular integration. To analyze these neuronal pathways underlying visuo-vestibular integration, we developed a setup using a lamprey eye-brain-labyrinth preparation, which allowed coordinating electrophysiological recordings, vestibular stimulation with a moving platform, and visual stimulation via screens. Lampreys exhibit robust visuo-vestibular integration, with optokinetic information processed in the pretectum that can be downregulated from tectum. Visual and vestibular inputs are integrated at several subcortical levels. Additionally, saccades are present in the form of nystagmus. Thus, all basic components of the visuo-vestibular control of gaze were present already at the dawn of vertebrate evolution.


Assuntos
Reflexo Vestíbulo-Ocular , Vestíbulo do Labirinto , Animais , Movimentos Oculares , Estimulação Luminosa , Reflexo Vestíbulo-Ocular/fisiologia , Movimentos Sacádicos , Vestíbulo do Labirinto/fisiologia
12.
J Int Adv Otol ; 18(5): 441-446, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35971266

RESUMO

The central vestibular compensation reduces vestibular symptoms and helps individuals improve balance affected by vestibular dysfunction. The video head impulse test provides an opportunity to study central vestibular compensation objectively. This study aims to methodically present existing information about the video head impulse test as a measure to evaluate central vestibular compensation in patients with unilateral vestibular dysfunction. Literature review comprised 12 research articles selected based on pre-set criteria and timeline (January 2010 to June 2020). The findings indicate that the appropriate video head impulse test measures to evaluate central vestibular compensation after the occurrence of temporary unilateral vestibular dysfunction are the improvement in vestibulo-ocular reflex gain. And, for permanent unilateral vestibular dysfunction are reduction in catch-up saccades percentage, velocity, amplitude, latency, and Perez and Rey score.


Assuntos
Teste do Impulso da Cabeça , Vestíbulo do Labirinto , Humanos , Reflexo Vestíbulo-Ocular , Movimentos Sacádicos
13.
Sensors (Basel) ; 22(15)2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35957391

RESUMO

Motion platforms have been used in simulators of all types for several decades. Since it is impossible to reproduce the accelerations of a vehicle without limitations through a physically limited system (platform), it is common to use washout filters and motion cueing algorithms (MCA) to select which accelerations are reproduced and which are not. Despite the time that has passed since their development, most of these algorithms still use the classical washout algorithm. In the use of these MCAs, there is always information that is lost and, if that information is important for the purpose of the simulator (the training simulators), the result obtained by the users of that simulator will not be satisfactory. This paper shows a case study where a BMW 325Xi AUT fitted with a sensor, recorded the accelerations produced in all degrees of freedom (DOF) during several runs, and data have been introduced in mathematical simulation software (washout + kinematics + actuator simulation) of a 6DOF motion platform. The input to the system has been qualitatively compared with the output, observing that most of the simulation adequately reflects the input to the system. Still, there are three events where the accelerations are lost. These events are considered by experts to be of vital importance for the outcome of a learning process in the simulator to be adequate.


Assuntos
Condução de Veículo , Enjoo devido ao Movimento , Vestíbulo do Labirinto , Simulação por Computador , Humanos , Movimento (Física) , Sensação
14.
Otol Neurotol ; 43(9): e1045-e1048, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36026590

RESUMO

OBJECTIVES: The main objective was to describe the nystagmus observed during benign paroxysmal vertigo (BPV) of childhood, which is one of the criteria included in the three versions of the International Classification of Headache Disorders that has never been specified. The secondary objectives were to emphasize the usefulness of a mobile phone to record nystagmus and discuss the physiopathology of this nystagmus. PATIENT: A 6-year-old boy complained of approximately 30 to 50 vertigo attacks, most of them lasting around 1 minute, during a 6-month period. INTERVENTION: Otoneurologic history and examination, audiovestibular exploration, and brain imaging were performed between the attacks. Video recording by the parents' mobile phone and video electroencephalography recording during a 1-day hospitalization were performed during the episodes. MAIN OUTCOME MEASURE: Analysis of seven video recordings performed by the parents and four during a 1-day hospitalization, as well as follow-up. RESULTS: The assessment between the attacks confirmed the diagnosis of BPV according to International Classification of Headache Disorders criteria. Video recordings constantly demonstrated a strong left horizontal nystagmus present at fixation in all direction of gaze, enhanced in left gaze. This nystagmus was associated with a rightward body deviation. CONCLUSION: The clinical presentation was more consistent with a peripheral vestibular deficit than with a central disorder. We encourage video recording of their child by the parents because it will help both to define the ictal nystagmus and to understand the underlying pathophysiology. The latter is discussed and is probably more complex than initially thought in BPV.


Assuntos
Transtornos da Cefaleia , Nistagmo Patológico , Vestíbulo do Labirinto , Vertigem Posicional Paroxística Benigna/complicações , Criança , Cefaleia/diagnóstico , Cefaleia/etiologia , Transtornos da Cefaleia/complicações , Humanos , Masculino , Nistagmo Patológico/etiologia , Gravação em Vídeo
15.
Neurobiol Aging ; 119: 102-116, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36030560

RESUMO

Nearly 75% of older adults in the US report balance problems. Although it is known that aging results in widespread brain atrophy, less is known about how brain structure relates to balance in aging. We collected T1- and diffusion-weighted MRI scans and measured postural sway of 36 young (18-34 years) and 22 older (66-84 years) adults during eyes open, eyes closed, eyes open-foam, and eyes closed-foam conditions. We calculated summary measures indicating visual, proprioceptive, and vestibular contributions to balance. Across both age groups, thinner cortex in multisensory integration regions was associated with greater reliance on visual inputs for balance. Greater gyrification within sensorimotor and parietal cortices was associated with greater reliance on proprioceptive inputs. Poorer vestibular function was correlated with thinner vestibular cortex, greater gyrification within sensorimotor, parietal, and frontal cortices, and lower free water-corrected axial diffusivity across the corona radiata and corpus callosum. These results expand scientific understanding of how individual differences in brain structure relate to balance and have implications for developing brain stimulation interventions to improve balance.


Assuntos
Equilíbrio Postural , Vestíbulo do Labirinto , Encéfalo/diagnóstico por imagem , Equilíbrio Postural/fisiologia , Propriocepção/fisiologia , Vestíbulo do Labirinto/fisiologia , Água
16.
Nat Commun ; 13(1): 5060, 2022 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-36030280

RESUMO

Motor circuits develop in sequence from those governing fast movements to those governing slow. Here we examine whether upstream sensory circuits are organized by similar principles. Using serial-section electron microscopy in larval zebrafish, we generated a complete map of the gravity-sensing (utricular) system spanning from the inner ear to the brainstem. We find that both sensory tuning and developmental sequence are organizing principles of vestibular topography. Patterned rostrocaudal innervation from hair cells to afferents creates an anatomically inferred directional tuning map in the utricular ganglion, forming segregated pathways for rostral and caudal tilt. Furthermore, the mediolateral axis of the ganglion is linked to both developmental sequence and neuronal temporal dynamics. Early-born pathways carrying phasic information preferentially excite fast escape circuits, whereas later-born pathways carrying tonic signals excite slower postural and oculomotor circuits. These results demonstrate that vestibular circuits are organized by tuning direction and dynamics, aligning them with downstream motor circuits and behaviors.


Assuntos
Vestíbulo do Labirinto , Peixe-Zebra , Animais , Movimentos Oculares , Sensação Gravitacional , Larva
17.
J Vis Exp ; (186)2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35993707

RESUMO

Vestibular perceptual thresholds refer to the motion intensity required to enable a participant to detect or discriminate a motion based on vestibular input. Using passive motion profiles provided by six degree-of-motion platforms, vestibular perceptual thresholds can be estimated for any kind of motion and thereby target each of the sub-components of the vestibular end-organ. Assessments of vestibular thresholds are clinically relevant as they complement diagnostic tools such as caloric irrigation, the head impulse test (HIT), or vestibular evoked myogenic potentials (VEMPs), which only provide information on sub-components of the vestibular system, but none of them allow for assessing all components. There are several methods with different advantages and disadvantages for estimating vestibular perceptual thresholds. In this article, we present a protocol using an adaptive staircase algorithm and sinusoidal motion profiles for an efficient estimation procedure. Adaptive staircase algorithms consider the response history to determine the peak velocity of the next stimuli and are the most commonly used algorithms in the vestibular domain. We further discuss the impact of motion frequency on vestibular perceptual thresholds.


Assuntos
Potenciais Evocados Miogênicos Vestibulares , Vestíbulo do Labirinto , Teste do Impulso da Cabeça , Humanos , Movimento (Física) , Potenciais Evocados Miogênicos Vestibulares/fisiologia , Vestíbulo do Labirinto/fisiologia
18.
Brain Inj ; 36(8): 911-920, 2022 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35918848

RESUMO

PRIMARY OBJECTIVE: To review the pathway to care for treatment and management of patients receiving visual and vestibular rehabilitation after mild traumatic brain injury (mTBI). METHODS & PROCEDURES: English scientific peer-reviewed articles from PubMed, CINAHL, Embase, and PsycINFO between 2000 and 2020 were first screened by title and abstract, then those selected underwent full-text review and analysis. MAIN OUTCOMES & RESULTS: The database search yielded 1640 results and after title and abstract review, 75 articles were selected for full-text screening, from which 8 were included in the qualitative synthesis. Current evidence includes a limited number of retrospective cohort studies and case studies. CONCLUSIONS: Many patients with visual and vestibular deficits following mTBI do not receive rehabilitation services until months following their injury as there is no standardized pathway to care for patients for visual and vestibular rehabilitation. Barriers to establishing a standardized pathway are the lack of natural history data for visual and vestibular function following mTBI and the lack of randomized clinical trials establishing the efficacy of rehabilitation in patients following mTBI.


Assuntos
Concussão Encefálica , Vestíbulo do Labirinto , Concussão Encefálica/diagnóstico , Humanos , Estudos Retrospectivos
19.
J Neurophysiol ; 128(2): 364-377, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35830608

RESUMO

The inner ear of teleost fishes is composed of three paired multimodal otolithic end organs (saccule, utricle, and lagena), which encode auditory and vestibular inputs via the deflection of hair cells contained within the sensory epithelia of each organ. However, it remains unclear how the multimodal otolithic end organs of the teleost inner ear simultaneously integrate vestibular and auditory inputs. Therefore, microwire electrodes were chronically implanted using a 3-D printed micromanipulator into the utricular nerve of oyster toadfish (Opsanus tau) to determine how utricular afferents respond to conspecific mate vocalizations termed boatwhistles (180 Hz fundamental frequency) during movement. Utricular afferents were recorded while fish were passively moved using a sled system along an underwater track at variable speeds (velocity: 4.0-12.5 cm/s; acceleration: 0.2-2.6 cm/s2) and while fish freely swam (velocity: 3.5-18.6 cm/s; acceleration: 0.8-29.8 cm/s2). Afferent fiber activities (spikes/s) increased in response to the onset of passive and active movements; however, afferent fibers differentially adapted to sustained movements. In addition, utricular afferent fibers remained sensitive to playbacks of conspecific male boatwhistle vocalizations during both passive and active movements. Here, we demonstrate in alert toadfish that utricular afferents exhibit enhanced activity levels (spikes/s) in response to behaviorally relevant acoustic stimuli during swimming.NEW & NOTEWORTHY The inner ear of teleost fishes is composed of three paired multimodal otolithic end organs, which are sensitive to vestibular and auditory inputs. Previous studies investigating inner ear functions have primarily focused on the effects of unimodal stimuli; therefore, it remains unclear how otolithic end organs simultaneously encode multiple stimuli. Here, we show that utricular afferents remain sensitive to behaviorally relevant acoustic stimuli during swimming.


Assuntos
Batracoidiformes , Vestíbulo do Labirinto , Estimulação Acústica , Animais , Batracoidiformes/fisiologia , Células Ciliadas Auditivas , Masculino , Sáculo e Utrículo
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