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Context: Sports-related concussions are commonly occurring injuries as a result of sports and recreation that may cause alterations in brain functioning. It is important to be able to evaluate the impact of these injuries on function to manage the injury recovery and ensure recovery. Recent literature suggests the use of objective evaluation strategies in a multifaceted approach to evaluate and manage these injuries. It is important to understand the relationships between the assessments and how best to utilize each assessment. The purpose of this study was to investigate if relationships exist between measures of vestibular function at baseline in assessments that may be used following sports-related concussions. Additionally, a secondary purpose was to determine if self-reported symptoms were related to performance on the assessments. This study aimed to identify if these assessments measured independent functions of the vestibulo–ocular reflex or if some redundancy existed among the assessment strategies. Design: A cross-sectional study design was used in a cohort of collegiate athletes ages 18–24. Methods: Participants completed demographics questionnaires, the Post-Concussion Symptom Scale, Gaze Stabilization Test, and Concussion Balance Test. Spearman rho correlations were used to examine the relationships between the measures. Results: One hundred and thirty-five collegiate athletes (82 males and 53 females) were included, representative of 3 sports (cheerleading, soccer, and football) with a mean age of 19.77 (1.42) years old. There were weak to moderate, significant relationships between measures of Gaze Stabilization Test and Concussion Balance Test errors (r =.20–.31, P =.001–.03). Conclusions: The direction of these relationships indicated that greater Concussion Balance Test errors were associated with greater Gaze Stabilization Test performance. These relationships may be attributed to the difficulty created by the foam conditions and the integration of more complex sensory tasks required to maintain balance during the more difficult conditions. [ABSTRACT FROM AUTHOR]

Oculomotor deficits are common in hereditary ataxia, but disproportionally neglected in clinical ataxia scales and as outcome measures for interventional trials. Quantitative assessment of oculomotor function has become increasingly available and thus applicable in multicenter trials and offers the opportunity to capture severity and progression of oculomotor impairment in a sensitive and reliable manner. In this consensus paper of the Ataxia Global Initiative Working Group On Digital Oculomotor Biomarkers, based on a systematic literature review, we propose harmonized methodology and measurement parameters for the quantitative assessment of oculomotor function in natural-history studies and clinical trials in hereditary ataxia. MEDLINE was searched for articles reporting on oculomotor/vestibular properties in ataxia patients and a study-tailored quality-assessment was performed. One-hundred-and-seventeen articles reporting on subjects with genetically confirmed (n=1134) or suspected hereditary ataxia (n=198), and degenerative ataxias with sporadic presentation (n=480) were included and subject to data extraction. Based on robust discrimination from controls, correlation with disease-severity, sensitivity to change, and feasibility in international multicenter settings as prerequisite for clinical trials, we prioritize a core-set of five eye-movement types: (i) pursuit eye movements, (ii) saccadic eye movements, (iii) fixation, (iv) eccentric gaze holding, and (v) rotational vestibulo-ocular reflex. We provide detailed guidelines for their acquisition, and recommendations on the quantitative parameters to extract. Limitations include low study quality, heterogeneity in patient populations, and lack of longitudinal studies. Standardization of quantitative oculomotor assessments will facilitate their implementation, interpretation, and validation in clinical trials, and ultimately advance our understanding of the evolution of oculomotor network dysfunction in hereditary ataxias.

Characterizing bedside oculomotor deficits is a critical factor in defining the clinical presentation of hereditary ataxias. Quantitative assessments are increasingly available and have significant advantages, including comparability over time, reduced examiner dependency, and sensitivity to subtle changes. To delineate the potential of quantitative oculomotor assessments as digital-motor outcome measures for clinical trials in ataxia, we searched MEDLINE for articles reporting on quantitative eye movement recordings in genetically confirmed or suspected hereditary ataxias, asking which paradigms are most promising for capturing disease progression and treatment response. Eighty-nine manuscripts identified reported on 1541 patients, including spinocerebellar ataxias (SCA2, n = 421), SCA3 (n = 268), SCA6 (n = 117), other SCAs (n = 97), Friedreich ataxia (FRDA, n = 178), Niemann-Pick disease type C (NPC, n = 57), and ataxia-telangiectasia (n = 85) as largest cohorts. Whereas most studies reported discriminatory power of oculomotor assessments in diagnostics, few explored their value for monitoring genotype-specific disease progression (n = 2; SCA2) or treatment response (n = 8; SCA2, FRDA, NPC, ataxia-telangiectasia, episodic-ataxia 4). Oculomotor parameters correlated with disease severity measures including clinical scores (n = 18 studies (SARA: n = 9)), chronological measures (e.g., age, disease duration, time-to-symptom onset; n = 17), genetic stratification (n = 9), and imaging measures of atrophy (n = 5). Recurrent correlations across many ataxias (SCA2/3/17, FRDA, NPC) suggest saccadic eye movements as potentially generic quantitative oculomotor outcome. Recommendation of other paradigms was limited by the scarcity of cross-validating correlations, except saccadic intrusions (FRDA), pursuit eye movements (SCA17), and quantitative head-impulse testing (SCA3/6). This work aids in understanding the current knowledge of quantitative oculomotor parameters in hereditary ataxias, and identifies gaps for validation as potential trial outcome measures in specific ataxia genotypes.

Background: In patients presenting with acute prolonged vertigo and/or gait imbalance, the HINTS [Head-Impulse, Nystagmus, Test-of-Skew] are very valuable. However, their application may be limited by lack of training and absence of vertigo/nystagmus. Alternatively, a graded gait/truncal-instability (GTI, grade 0–3) rating may be applied. Methods: We performed a systematic search (MEDLINE/Embase) to identify studies reporting on the diagnostic accuracy of bedside examinations in adults with acute vestibular syndrome. Diagnostic test properties were calculated for findings using a random-effects model. Results were stratified by GTI-rating used. Results: We identified 6515 articles and included 18 studies (n = 1025 patients). Ischemic strokes (n = 665) and acute unilateral vestibulopathy (n = 306) were most frequent. Grade 2/3 GTI had moderate sensitivity (70.8% [95% confidence-interval (CI) = 59.3–82.3%]) and specificity (82.7 [71.6–93.8%]) for predicting a central cause, whereas grade 3 GTI had a lower sensitivity (44.0% [34.3–53.7%] and higher specificity (99.1% [98.0–100.0%]). In comparison, diagnostic accuracy of HINTS (sensitivity = 96.8% [94.8–98.8%]; specificity = 97.6% [95.3–99.9%]) was higher. When combining central nystagmus-patterns and grade 2/3 GTI, sensitivity was increased to 76.4% [71.3–81.6%] and specificity to 90.3% [84.3–96.3%], however, no random effects model could be used. Sensitivity was higher in studies using the GTI rating (grade 2/3) by Lee (2006) compared to the approach by Moon (2009) (73.8% [69.0–78.0%] vs. 57.4% [49.5–64.9%], p = 0.001). Conclusions: In comparison to HINTS, the diagnostic accuracy of GTI is inferior. When combined with central nystagmus-patterns, diagnostic accuracy could be improved based on preliminary findings. GTI can be readily applied in the ED-setting and also in patients with acute imbalance syndrome. [ABSTRACT FROM AUTHOR]

Disease-specific oculomotor assessments play a crucial role in the early diagnosis of hereditary cerebellar ataxias. Whereas several studies have reported on quantitative oculomotor and vestibular measurements in Friedreich's Ataxia (FRDA), the value of specific oculomotor paradigms remains unclear. We aimed to address this knowledge gap through a systematic literature review and providing disease-specific recommendations for a tailored set of eye-movement recordings in FRDA. MEDLINE and Embase were searched for studies reporting on quantitative oculomotor and/or vestibular measurements in FRDA-patients. Data on oculomotor and vestibular parameters were extracted and correlations with a range of clinical parameters were sought. Included studies (n = 17) reported on 185 patients. Abnormalities observed included the presence of saccadic intrusions (143/161) such as square-wave jerks (SWJ, 90/109) and ocular flutter (21/43), impaired eccentric gaze-holding (40/104), abnormal pursuit (81/93) and angular vestibulo-ocular reflex (aVOR) deficits (39/48). For visually-guided saccades (VGS), we frequently observed increases in saccade latency (27/38) and dysmetric saccades (71/93), whereas saccade velocity was more often preserved (37/43). Augmented anti-saccade (AS) latency, downbeat nystagmus and frequent macro-SWJ correlated with disease duration. Increased AS-latency and VGS-latency, frequent macro-SWJ, reduced aVOR-gain and augmented aVOR peak-latency correlated with disease severity. A broad range of oculomotor and vestibular deficits are documented in the literature. Impairments in pursuit, saccades and aVOR-responses are most commonly reported, and as such, should be prioritized as disease markers. Quantitative oculomotor testing in FRDA may facilitate early diagnosis and prove valuable in monitoring disease progression and treatment response. [ABSTRACT FROM AUTHOR]

Suffering an acute asymmetry in vestibular function (i.e., vestibular neuritis) causes increased sway. Non-causal studies report associations between lateral semicircular canal function and balance ability, but direct links remain controversial. We investigate the immediate effect on body sway after unilateral vestibulo-ocular reflex (VOR) gain down adaptation simulating acute peripheral vestibular hypofunction. Eighteen healthy adults, mean age 27.4 (± 12.4), stood wearing an inertial measurement device with their eyes closed on foam before and after incremental VOR gain down adaptation to simulate mild unilateral vestibular neuritis. Active head impulse VOR gain was measured before and after the adaptation to ensure VOR gain adaptation. Percentage change for VOR gain was determined. Sway area was compared before and after VOR adaptation. VOR gain decreased unilaterally exceeding meaningful change values. Sway area was significantly greater immediately after VOR gain down adaptation, but quickly returned to baseline. In a subset of subjects VOR gain was re-assessed and found to remain adapted despite sway normalization. These results indicate that oculomotor adaptation targeting the lateral semicircular canal VOR pathway has an immediate, albeit transient increase in body sway. Rapid return of body sway to baseline levels suggests dynamic sensory reweighting between vestibular and somatosensory inputs to resolve the undesirable increased body sway. [ABSTRACT FROM AUTHOR]

This study aims to establish a set of normal values for the objective evaluation of ocular movements using videonystagmography (VNG). Thirty individuals aged between 18 and 50 years, with no history of vestibular symptoms, recurrent headaches, central nervous system (CNS) symptoms, or cochlear symptoms, were selected. The assessment of five types of ocular movements (saccades, pursuit, optokinetic tests, spontaneous nystagmus, and gaze tests) were conducted using VNG. Normal ranges were established for different parameters of saccades, including latency, precision, and velocity in both horizontal and vertical directions for each eye. Pursuit gain was calculated for each eye in all four directions. Optokinetic gain was determined when the stimulation screen moved in all four directions. Symmetric responses were observed in all subjects. No spontaneous nystagmus was observed with fixation, although two participants exhibited nystagmus upon removal of fixation. Gaze tests revealed no abnormalities. [ABSTRACT FROM AUTHOR]

The purpose of this case report is to highlight both the feasibility and clinical utility of remote camera video head impulse testing (vHIT) in children <3 years. Five cases are described where remote camera vHIT was used to quantify ear specific semicircular function in children at risk for vestibular dysfunction. Remote camera vHIT is a helpful clinical tool for quantifying ear specific semicircular function in children between 6 and 31 months. Remote camera vHIT is feasible and provides ear specific information regarding semicircular canal function, which can be used to augment or validate the presence of vestibular dysfunction in children <3 years. Laryngoscope, 134:5201–5206, 2024 [ABSTRACT FROM AUTHOR]

Swim tests are highly effective for identifying vestibular deficits in rodents by offering significant vestibular motor challenges with reduced proprioceptive input, unlike rotarod and balance beam tests. Traditional swim tests rely on subjective assessments, limiting objective quantification and reproducibility. We present a novel instrumented swim test using a miniature motion sensor with a 3D accelerometer and 3D gyroscope affixed to the rodent's head. This setup robustly quantifies six-dimensional motion—three translational and three rotational axes—during swimming with high temporal resolution. We demonstrate the test's capabilities by comparing head movements of Gpr156-/- mutant mice, which have impaired otolith organ development, to their heterozygous littermates. Our results show axis-specific differences in head movement probability distribution functions and dynamics that identify mice with the Gpr156 mutation. Axis-specific power spectrum analyses reveal selective movement alterations within distinct frequency ranges. Additionally, our spherical visualization and 3D analysis quantifies swimming performance based on head vector distance from upright. We use this analysis to generate a single classifier metric—a weighted average of an animal's head deviation from upright during swimming. This metric effectively distinguishes animals with vestibular dysfunction from those with normal vestibular function. Overall, this instrumented swim test provides quantitative metrics for assessing performance and identifying subtle, axis- and frequency-specific deficits not captured by existing systems. This novel quantitative approach can enhance understanding of rodent sensorimotor function including enabling more selective and reproducible studies of vestibular-motor deficits. [ABSTRACT FROM AUTHOR]

Background: Anti-phospholipid syndrome (APS) has emerged as a significant issue in autoimmune diseases over recent decades. Its hallmark feature is thromboembolic events, potentially affecting any vascularized area including the microcirculation of the inner ear. Since the first case report of APS-related audiovestibular dysfunction described in 1993, numerous reports have explored the association between APS-related antibodies and audiovestibular dysfunction. These studies indicate a higher prevalence of APS-related antibodies in patients with sensorineural hearing loss compared to healthy controls. Unlike other idiopathic hearing loss disorders, audiovestibular dysfunction associated with APS may respond to appropriate treatments, highlighting the importance of timely recognition by clinicians to potentially achieve favorable outcomes. Therefore, this systematic review aims to consolidate current evidence on the characteristics, pathophysiology, assessment, and management of audiovestibular dysfunction linked to APS. Methods: This systematic review utilized electronic searches of the PubMed, Embase, ClinicalKey, Web of Science, and ScienceDirect online platforms. The initial search was performed on 27 January 2024, with the final update search completed on 20 June 2024. Results: Based on theoretical pathophysiology, anticoagulation emerges as a pivotal treatment strategy. Additionally, drawing from our preliminary data, we propose a modified protocol combining anticoagulants, steroids, and non-invasive brain stimulation to offer clinicians a novel therapeutic approach for managing these symptoms. Conclusions: Clinicians are encouraged to remain vigilant about the possibility of APS and its complex audiovestibular manifestations, as prompt intervention could stabilize audiovestibular function effectively. [ABSTRACT FROM AUTHOR]

Dizziness following mild traumatic brain injury (mTBI), or concussion, is common and can encompass multiple sensations reflecting diverse aetiologies. This exploratory study investigated the types of dizzy sensations experienced, their evolution, and relationship with other post-concussion symptoms. Thirty New Zealanders (24 female) aged 49 ± 16 years who experienced dizziness or imbalance following their injury completed the Dizziness Handicap Inventory, Visual Vertigo Analogue Scale, and the Hospital Anxiety and Depression Scale. Additional custom questionnaires probed subjective experiences of dizziness and balance, headaches, and difficulties with auditory processing and vision. Just over half the participants (56.7%) experienced a single mTBI. The median time interval since the injury was 16 months (IQR = 24 months). Participants usually reported multiple dizzy symptoms which developed within a week of the injury, although delays of up to six months were reported. Most participants (70%) felt their symptoms improved over time, while lack of improvement was associated with a history of multiple mTBI (P = 0.020). Moderate to strong correlations between questionnaire scores representing dizziness handicap, visual vertigo severity, and auditory processing difficulties (P < 0.001) suggest that dizziness and sensory impairment following mTBI are multi-modal and likely to benefit from holistic, multidisciplinary treatment. [ABSTRACT FROM AUTHOR]

Objective: To conduct a retrospective cross‐sectional multicenter study to validate the relationships between migraine‐associated symptoms. Background: Symptoms associated with headache—photophobia and phonophobia, nausea, and/or vomiting—are required criteria for migraine diagnosis based on the International Classification of Headache Disorders‐Third Edition (ICHD‐3). However, individuals with migraine report high rates of other symptoms (e.g., lightheadedness, difficulty thinking). We recently completed a single‐center study assessing the relationships between an expanded set of migraine‐associated symptoms. Methods: A pre‐registered cross‐sectional multicenter retrospective analysis was conducted on standardized questionnaire data of youth ages 6–17 years from two headache registries at pediatric tertiary care centers. Cluster Analysis of Migraine‐associated Symptoms (CAMS) was implemented to assess associations between 11 migraine‐associated symptoms. We explored differences between the two centers, and how CAMS was associated with demographics, including sex and age, and headache burden. Results: There were 10,721 participants who were 66.5% female and had a median (interquartile range) age of 13 (10–15) years. The first three CAMS dimensions accounted for 46.5% of the variance and were consistent across sites. The first dimension indicated those reporting any migraine‐associated symptoms were likely to report multiple. The second dimension separated symptoms into those included in ICHD‐3 migraine diagnostic criteria and non‐ICHD symptoms (e.g., lightheadedness, difficulty thinking). The third dimension separated sensory hypersensitivity and vestibular symptoms. An abundance of migraine‐associated symptoms correlated with greater headache severity (Spearman's ρ = 0.18, 95% confidence interval [CI] 0.17–0.20; small effect size) and disability (ρ = 0.26, 95% CI 0.25–0.28; small effect size). We also observed differences in associated symptoms across age and sex. Discussion: Associations between an expanded set of migraine‐associated symptoms are informative for headache burden and reveal intriguing changes across child development and sex. We were able to replicate findings across two centers, indicating that these symptom clusters are inherent to migraine. Plain Language Summary: The presence of symptoms such as light or sound sensitivity, nausea, and vomiting can help clinicians differentiate between migraine and other headache disorders, such as tension‐type headache. However, people with migraine commonly experience symptoms that are not part of migraine diagnostic criteria per the International Classification for Headache Disorders‐Third Edition criteria, including lightheadedness, vision changes, and vertigo. In this study, we found that by considering these other associated symptoms, we were able to better understand the burden of headache in children and adolescents; e.g., we found that having more associated symptoms was associated with more headache severity and greater headache impact in children and teenagers. [ABSTRACT FROM AUTHOR]

Objectives: We used Cluster Analysis of Migraine‐associated Symptoms (CAMS) to critically evaluate current International Classification of Headache Disorders‐Third Edition (ICHD‐3) migraine‐associated symptoms criteria. Background: Diagnostic criteria play a central role in guiding clinical trial inclusion, and therefore available treatments. Migraine and tension‐type headaches (TTH) are differentiated in ICHD‐3 by many headache characteristics, including associated symptoms. A diagnosis of probable migraine indicates some but not all features of migraine are met. Photophobia and phonophobia, or nausea and/or vomiting, are required to meet a diagnosis of migraine; however, CAMS—a model that describes associated symptoms across youth with headache—indicates that a broader range of symptoms contain information about migraine burden. Methods: In this multisite retrospective cross‐sectional study, we evaluated ICHD‐3 migraine criteria. Youth aged 6–17 years with migraine (including probable migraine) or TTH were included in the analysis. We used CAMS to evaluate the migraine‐associated symptom criterion. With CAMS as a guide, we evaluated how changes to the migraine‐associated symptom criterion altered who met the diagnosis of migraine. Results: Of the 9017 participants included in this study, 66.7% were female and had a median (interquartile range) age of 13 (10–15) years. Most participants had migraine or probable migraine (99.0%), and the remainder had TTH (1.0%). A sizable percentage (10.1%) of youth under the umbrella diagnosis of migraine were diagnosed with probable migraine because they did not meet migraine‐associated symptom criterion D; however, many in this group reported several non‐ICHD migraine‐associated symptoms. We explored alterations to criterion D based on CAMS. Allowing for photophobia or phonophobia re‐categorized 55.6% of youth as having migraine, though some only had one symptom. Including lightheadedness or lightheadedness and spinning re‐categorized 19.7% and 25.8% of youth with migraine, respectively, but all of those who were re‐categorized had at least two migraine‐associated symptoms. Conclusion: The ICHD‐3 captures the most prevalent migraine‐associated symptoms; however, many youths with probable migraine who do not meet full criteria due to insufficient associated symptoms nonetheless experience multiple non‐ICHD migraine‐associated symptoms. Changes to criterion D should be considered for the ICHD‐4. Plain Language Summary: For clinicians to make a diagnosis of migraine based on International Classification of Headache Disorders‐Third Edition (ICHD‐3) criteria, patients must have headache‐associated nausea, vomiting, or light and sound sensitivity (criterion D). However, migraine can also be associated with other symptoms like lightheadedness, difficulties with thinking, and vertigo. In this study of youth aged 6–17 years with migraine, probable migraine, or tension‐type headache, we looked at how altering the ICHD‐3 criterion D changed participants' diagnosis based on their symptoms; overall, our results suggest that the next version of ICHD should account for the fact that many youth who do not experience nausea, vomiting, or light and sound sensitivities still experience manyx other migraine associated symptoms. [ABSTRACT FROM AUTHOR]

Background and Objective: In the US military, traumatic brain injury (TBI) is of distinct importance, at home and in the deployed setting, and is considered a "signature injury of the wars in Afghanistan and Iraq." Since 2000, an estimated 468 424 service members (SMs) have been diagnosed with at least one TBI. We examined the clinical trajectories of a group of 18 comorbidities before and after a military-sustained mild TBI (mTBI). Methods: Without making assumptions on causality, a group of 18 conditions often co-occurring with mTBI were identified through literature review and TBI subject matter workgroup consensus. Using data from Military Health System Data Repository, we identified SMs whose first lifetime military mTBI occurred between October 1, 2016, and October 30, 2019. Correlation analyses were used to determine the linear relationship between comorbidities prior to and after mTBI diagnosis. Changes in the period prevalence of comorbidities was calculated. Results: We identified 42 018 SMs with a first lifetime military mTBI, of which 77.6% had at least one comorbidity. Identified SMs were mostly young (46.1% ages 18-24 years), male (81.4%), and White (64.1%). Up to 180 days prior to an mTBI, the most frequently identified conditions were sleep-related conditions (21.7%), headaches (19.4%), posttraumatic stress disorders (PTSDs) (17.8%), anxiety disorders (11.3%), and cervicogenic disorders (eg, cervicalgia) (10.9%). In the period following mTBI diagnosis, the prevalence of diagnosed conditions increased, especially for visual disturbances (327.2%), cognitive conditions (313.9%), vestibular conditions (192.6%), those related to headache (152.2%), and hearing (72.9%). Sleep-related conditions showed moderate positive correlation with a group of co-occurring conditions, led by cognitive conditions (ÿc = 0.50), anxiety disorders (ÿc = 0.42), PTSDs (ÿc =0.43), and headaches and related conditions (ÿc = 0.38). Conclusion: Results indicate that caring for SMs with mild TBI requires a holistic approach, one that considers the complex nature of SM conditions, prior to sustaining their mTBI, as well as after injury. We found a complex correlation of conditions that suggest SMs with mTBI are undergoing a multifaceted experience, one that may require the development of a targeted multidimensional clinical practice recommendation and practice. [ABSTRACT FROM AUTHOR]

This retrospective study describes the surgical outcomes of our first 20 transgender women to undergo feminization thyroid laryngochondroplasty (FLC) by a direct transvestibular FLC (DTV-FLC) approach from December 2019 to October 2023. The medical records of all patients were retrieved and reviewed. Data on the operative, postoperative, and follow-up courses, complications, and functional and cosmetic outcomes were retrieved. The cosmetic results were evaluated by four independent facial plastic surgeons. Thirteen patients underwent DTV-FLC combined with genioplasty or genioplasty with mandibular angle reduction and seven underwent isolated DTV-FLC. DTV-FLC was feasible in all planned cases. Complications (skin flap perforation, thyroid cartilage fracture, mental hypoesthesia, hematoma, dehiscence of the vestibular incision, vestibular scar adhesions, and anemia) were minor and resolved spontaneously. The preoperative grade of thyroid cartilage protrusion was 1.9 ± 0.9 on a scale from 1 to 3. The postoperative cosmetic results of 18 patients were judged as having improved (a score of 2.1 ± 0.8 on a scale from −1 to 3). Eighteen patients were satisfied with the cosmetic result, one was dissatisfied (the revision surgery patient), and one was lost to follow-up. In conclusion, DTV-FTLC is a valid surgical approach for FLC, yielding high patient satisfaction and good cosmetic results. [ABSTRACT FROM AUTHOR]

Animal studies of the mammalian vestibular system began at the University of Otago in 1987. From approximately 2000, these studies focused on the effects of vestibular lesions and stimulation, on spatial memory and the hippocampus. Our research has shown that, as well as the deficits in the vestibulo-ocular and vestibulo-spinal reflexes that occur following vestibular dysfunction, vestibular loss may also cause cognitive disorders, especially spatial memory deficits, some of which are related to the contribution of ascending vestibular pathways to the function of the limbic system and neocortex in regulating spatial orientation. In addition to behavioural demonstrations of spatial memory deficits, we have demonstrated that vestibular loss is associated with a variety of dysfunctional changes in the hippocampus, which may be responsible for the spatial memory deficits. These memory deficits are unlikely to be due to hearing loss, problems with motor control, oscillopsia or anxiety and depression. These animal studies have raised awareness of cognitive deficits associated with vestibular disorders and contributed to their recognition and treatment. [ABSTRACT FROM AUTHOR]

AbstractObjectiveDesignStudy sampleResultsConclusionsOur primary purpose was evaluation of early benefits of lifestyle modification on symptoms of vestibular migraine. The secondary purpose was to determine if a patient’s global sense of coping relates to outcomes with lifestyle modification.Prospective observational cohort. Participants completed questionnaires related to dizziness handicap, headache disability, and adherence to lifestyle modifications at baseline and weekly over 30 d. Sense of coping was measured pre-intervention.Thirty-eight patients with vestibular migraine diagnosed in tertiary care setting between 2022 and 2023.Symptoms were better at all four weeks post-intervention than pre-intervention (p < 0.01), with no difference across weeks two through four (p > 0.10) when symptoms were lowest and stable. By week two, 52% and 18.5% of participants had significant improvement in dizziness and headache compared to published critical difference scores, respectively. Sense of coping was inversely correlated with dizziness (R = −0.53, p < 0.00001) and headache (R = −0.64, p < 0.0001).Lifestyle modification reduced dizziness and headache in many vestibular migraineurs in the first two weeks following intervention. Improvement in restful sleep was associated with improvement in symptoms. Sense of coping did not predict improvement but was inversely related to symptoms. Lifestyle modification could be considered as sole management or in addition to pharmacological intervention. [ABSTRACT FROM AUTHOR]

Background: Multiple Sclerosis (MS) is the most prevalent autoimmune neurological condition in the world, leading to a wide variety of symptoms, including balance disorders. Objective: To evaluate the angular vestibulo–ocular reflex (aVOR) of all six semicircular canals (SCCs) through Head Impulse (HIMP) and Suppression HIMP (SHIMP) paradigms and any correlations with clinical balance scales. Methods: All participants were assessed using the Expanded Disability Status Scale (EDSS), Berg Balance Scale (BBS), and Mini-BESTest (MBT). Vestibular function was measured by video Head Impulse Test (vHIT), obtaining aVOR gain for each SSC. Results: Twenty-seven PwMS (mean age 47.93 ± 8.51 years old, 18 females) were recruited. Most of the patients (81.48%) presented abnormal aVOR gains for at least one SSC. A moderate to strong correlation between aVOR gains of the left anterior SSC and, respectively, the MBT and the BBS was found. The subgroup analysis, based on the EDSS class, confirmed the correlation with the BBS in the patients with the most significant disability. Conclusions: People with MS may present impairments of the aVOR in one or more semicircular canals. The aVOR gain impairment of the vertical semicircular canals correlates with balance and gait disorders identified through clinical scales in PwMS. [ABSTRACT FROM AUTHOR]

Objectives: The study objective was to investigate the influence of electrical stimulus properties on cervical and ocular vestibular‐evoked myogenic potentials to electrical stimulation by cochlear implants (e‐cVEMPs, e‐oVEMPs). Methods: E‐VEMPs were recorded in adult Nucleus cochlear implant (CI) patients using electric pulse trains (4 biphasic pulses at 1000 Hz burst rate). Ground path and stimulation electrodes were varied between monopolar stimulation at basal electrode contact E3 (MP1 + 2 E3), monopolar stimulation at apical electrode contact E20 (MP1 + 2 E20), and bipolar transmodiolar stimulation between E3 and E14 (BP E3‐E14). The electric pulse train was further varied to 2 pulses at 1000 Hz, 2 pulses at 500 Hz, and a single pulse, in patients with present e‐VEMP responses. VEMPs to bone‐conducted vibration (BCV) were recorded as reference in all participants. Results: Measurements were conducted in 30 ears of 27 participants (mean age 49.3 years, SD 12.7 years). E‐VEMPs were present in 13 ears (43%). 5 of the 13 cases showed e‐VEMPs but no BCV evoked VEMPs. Response numbers increased with increasing stimulation levels. The highest response rate of 40% was obtained for MP1 + 2 E3 stimulation. Stimulus variation did not affect response numbers. E‐VEMP amplitudes were comparable to BCV‐stimulated VEMPs. Latencies were up to 3.1 ms shorter for electric stimulation. Some patients showed e‐VEMP thresholds close to or below the electric hearing threshold level. Conclusion: The occurrence of e‐VEMPs is dependent on current path and stimulation level. Vestibular co‐stimulation by the CI is more likely in patients with high stimulation levels and for monopolar stimulation of basal electrode contacts. Level of Evidence: 4. [ABSTRACT FROM AUTHOR]

Introduction: Aging is associated with loss of balance, with falls being one of the leading causes of death among the elderly in the USA. Gaze stabilization exercises (GSE) improve balance control in vestibular populations and could be useful to prevent falls in healthy individuals. However, the extent to which aging affects head kinematics in GSE is unknown. Methods: Forty-eight younger (n = 25, 24 ± 6 years, 60% female) and older (n = 23, 66 ± 5 years, 56% female) adults completed six 30-s GSE. Participants were asked to maintain gaze fixation on a stationary target while continuously performing head movements in pitch (e.g., vertical) and yaw (e.g., horizontal) directions. The visual target was placed on the wall 1 m or 2 m away or handheld at arm's length. Head kinematics were recorded with an inertial measurement unit placed on the back of the participants' head. Results: Older adults took significantly more time (e.g., delay) to complete cycles of head rotation in both pitch and yaw compared to younger participants across all GSE. Such delay was further increased during yaw head rotation while fixating gaze of the 1 m target. The average peak velocity (APV) and average angular displacement (AAD), however, were equivalent between groups in all GSE. Conclusion: Aging leads to the maintenance of head rotation APV and AAD at the expense of delayed cycles of head rotation, suggesting an age-dependent prioritization strategy (e.g., adapt duration first, range second) during continuous head movements. The distance of the visual target and head movement direction influenced elderly performance and should be considered when prescribing GSE to older populations. [ABSTRACT FROM AUTHOR]

Galvanic Vestibular Stimulation (GVS) has been proposed as an alternative display modality to relay information without increasing demands on the visual or auditory sensory modalities of the wearer or in environments where those modalities cannot be used (e.g., covert night operations). We further investigated this concept with four experiments designed to test: (1) thresholds at which subjects could distinguish between different GVS current amplitudes and polarities, (2) thresholds at which different bipolar (i.e., sinusoidal waveform with current oscillating between left and right directions) current frequencies were distinguishable among room temperature, hot, cold, and windy environments, (3) effects of unipolar (i.e., sinusoidal waveform with current occurring in only the left or right direction) currents on balance performance, and (4) dual-task performance among frequency and polarity modulated GVS conditions during a concordant visual search task. Subjects reliably distinguished between current amplitudes that varied from a pedestal of ± 0.6 mA by a median of 0.03 mA (range of 0.02–0.32 mA) and between unipolar currents at a median amplitude of 0.55 mA (range of 0.32–0.83 mA). GVS frequency thresholds were robust to the environment conditions tested, with no statistical differences found. Sway and balance errors were increased with unipolar currents. GVS thresholds were not impacted by the dual-task paradigm, but the visual search scores were slightly elevated when congruently performing a polarity thresholding task. Overall findings continue to support GVS use as a display modality, but some limitations are noted, such as the use of unipolar currents under scenarios where postural control is important. [ABSTRACT FROM AUTHOR]

Background: The goal of post-stroke early rehabilitation is to regain ambulation, standing and balance. Objective: The purpose of this study was to investigate the effects of vestibular and somatosensory rehabilitation in addition to early rehabilitation on balance in patients with early subacute stroke. Design and setting: A randomized controlled trial was conducted at a university hospital. Methods: The study was included 52 hemiplegic hospitalized early suacute stroke patients. The experimental group (n: 30), was applied with vestibular and somatosensorial rehabilitation together with early rehabilitation. Vestibular exercises, included Cawthorne-Cooksey exercises, stimulate the vestibulo-ocular and vestibulo-spinal reflex. Somatosensory exercises, which included Frenkel exercises, stimulate the sensory proprioception and somatosensory systems. The control group (n: 22) patients with early subacute stroke were treated with the early rehabilitation program only. The balance parameters of the patients were evaluated with the Korebalance System, Functional Reach Test, Postural Assessment Scale for Stroke, and Functional Ambulation Scale. Results: The mean age of the patients was 67.32 ± 9.46 years, and the mean number of days that had passed since the stroke occurred was 17.90 ± 7.26. In calculating the balance scores, statistically significant differences were observed in the experimental and control groups, with a statistically greater improvement in the rehabilitation group. Statistically significant differences were determined between the groups in respect of the balance scores. Conclusions: Based on these findings, the use of vestibular and somatosensory rehabilitation can be recommended for better functioning of the compensatory mechanism of early subacute-stroke hemiplegic patients in early ambulation, and this can lead to considerably improved standing and dynamic upper and lower body balance. [ABSTRACT FROM AUTHOR]

Abstract Swim tests are highly effective for identifying vestibular deficits in rodents by offering significant vestibular motor challenges with reduced proprioceptive input, unlike rotarod and balance beam tests. Traditional swim tests rely on subjective assessments, limiting objective quantification and reproducibility. We present a novel instrumented swim test using a miniature motion sensor with a 3D accelerometer and 3D gyroscope affixed to the rodent’s head. This setup robustly quantifies six-dimensional motion—three translational and three rotational axes—during swimming with high temporal resolution. We demonstrate the test’s capabilities by comparing head movements of Gpr156 -/- mutant mice, which have impaired otolith organ development, to their heterozygous littermates. Our results show axis-specific differences in head movement probability distribution functions and dynamics that identify mice with the Gpr156 mutation. Axis-specific power spectrum analyses reveal selective movement alterations within distinct frequency ranges. Additionally, our spherical visualization and 3D analysis quantifies swimming performance based on head vector distance from upright. We use this analysis to generate a single classifier metric—a weighted average of an animal’s head deviation from upright during swimming. This metric effectively distinguishes animals with vestibular dysfunction from those with normal vestibular function. Overall, this instrumented swim test provides quantitative metrics for assessing performance and identifying subtle, axis- and frequency-specific deficits not captured by existing systems. This novel quantitative approach can enhance understanding of rodent sensorimotor function including enabling more selective and reproducible studies of vestibular-motor deficits.

Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population. Posture and gait control does not happen automatically, as previously believed, but rather requires continuous involvement of central nervous mechanisms. To effectively exert control over the body, the brain must integrate multiple streams of sensory information, including visual, vestibular, and somatosensory signals. The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work. Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults. Insufficient emphasis, however, has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance. In the present work, we review the contributions of somatosensory, visual, and vestibular modalities, along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease. We also review evidence of vestibular contributions to multisensory temporal binding windows, previously shown to be highly pertinent to fall risk in older adults. Lastly, we relate multisensory vestibular mechanisms to potential neural substrates, both at the level of neurobiology (concerning positron emission tomography imaging) and at the level of electrophysiology (concerning electroencephalography). We hope that this integrative review, drawing influence across multiple subdisciplines of neuroscience, paves the way for novel research directions and therapeutic neuromodulatory approaches, to improve the lives of older adults and patients with neurodegenerative diseases.

Background: Multiple Sclerosis (MS) is the most prevalent autoimmune neurological condition in the world, leading to a wide variety of symptoms, including balance disorders. Objective: To evaluate the angular vestibulo–ocular reflex (aVOR) of all six semicircular canals (SCCs) through Head Impulse (HIMP) and Suppression HIMP (SHIMP) paradigms and any correlations with clinical balance scales. Methods: All participants were assessed using the Expanded Disability Status Scale (EDSS), Berg Balance Scale (BBS), and Mini-BESTest (MBT). Vestibular function was measured by video Head Impulse Test (vHIT), obtaining aVOR gain for each SSC. Results: Twenty-seven PwMS (mean age 47.93 ± 8.51 years old, 18 females) were recruited. Most of the patients (81.48%) presented abnormal aVOR gains for at least one SSC. A moderate to strong correlation between aVOR gains of the left anterior SSC and, respectively, the MBT and the BBS was found. The subgroup analysis, based on the EDSS class, confirmed the correlation with the BBS in the patients with the most significant disability. Conclusions: People with MS may present impairments of the aVOR in one or more semicircular canals. The aVOR gain impairment of the vertical semicircular canals correlates with balance and gait disorders identified through clinical scales in PwMS.

Abstract Background Dizziness and vertigo are common referrals to Ear Nose Throat (ENT) outpatient services however these services have long waitlists for assessment. Primary contact physiotherapy-led vestibular clinics are recognized as improving access to care. This pilot study investigated agreement between physiotherapists and an ENT medical practitioner for diagnostic and management decisions in patients attending a primary contact physiotherapy-led vestibular clinic. Methods Prospective blinded inter-rater agreement study undertaken in an ENT primary contact physiotherapy-led vestibular clinic. Participants were adults referred to ENT from general practitioners, triaged (Category 2 or 3) to the primary contact physiotherapy-led vestibular clinic with clinical symptoms consistent with vestibular disorder. Primary outcome measures included agreement of diagnoses and management decisions made by an ENT medical practitioner and Physiotherapist based on a vestibular physiotherapy assessment. Adverse events were reviewed 11 months post data collection. Gwet’s first order agreement co-efficient (AC1) calculated inter-rater reliability between physiotherapy and ENT. Results Fifty-one participants were recruited consecutively from the primary contact physiotherapy-led vestibular clinic. Physiotherapy and ENT had a substantial agreement (AC1 0.613) on diagnosis. AC1 between physiotherapy and ENT for recommending Magnetic resonance imaging (0.810) and computerized tomography (0.935) both indicated near perfect agreement. There was moderate to near-perfect agreement regarding management recommendations between physiotherapy and ENT. Substantial agreement (AC1 0.720) was found for recommendations for ENT input, near perfect agreement (AC1 0.933) for neurology input and moderate agreement (AC1 0.574) for physiotherapy input. There were no adverse events from physiotherapist’s management decision, based on final recommendations undertaken 11-months post data collection. Conclusions Physiotherapists and ENT medical practitioner made comparable diagnostic and management decisions, based on physiotherapy and audiology hearing assessment, for adults with signs of vestibular dysfunction, within an ENT primary contact physiotherapy-led vestibular clinic. This study provides support for this type of Physiotherapy-led service in managing patients referred to an ENT service with vestibular dysfunction.

Abstract The present study explored the presence of torsional gaze-stabilization to proprioceptive neck activation in humans. Thirteen healthy subjects (6 female, mean age 25) were exposed to passive body rotations while maintaining a head-fixed, gravitationally upright, position. Participants were seated in a mechanical sled, their heads placed in a chin rest embedded in a wooden beam while wearing an eye tracker attached to the beam using strong rubber bands to ensure head stability. The body was passively rotated underneath the head both in darkness and while viewing a projected visual scene. Static torsional gaze positions were compared between the baseline position prior to the stimulation, and immediately after the final body tilt had been reached. Results showed that passive neck flexion produced ocular torsion when combined with a visual background. The eyes exhibited rotations in the opposite direction of the neck’s extension, matching a hypothetical head tilt in the same direction as the sled. This corresponded with a predicted head rotation aimed at straightening the head in relation to the body. No such response was seen during trials in darkness. Altogether, these findings suggest that proprioception may produce a predictive gaze-stabilizing response in humans.

Background: Dizziness and vertigo are common referrals to Ear Nose Throat (ENT) outpatient services however these services have long waitlists for assessment. Primary contact physiotherapy-led vestibular clinics are recognized as improving access to care. This pilot study investigated agreement between physiotherapists and an ENT medical practitioner for diagnostic and management decisions in patients attending a primary contact physiotherapy-led vestibular clinic. Methods: Prospective blinded inter-rater agreement study undertaken in an ENT primary contact physiotherapy-led vestibular clinic. Participants were adults referred to ENT from general practitioners, triaged (Category 2 or 3) to the primary contact physiotherapy-led vestibular clinic with clinical symptoms consistent with vestibular disorder. Primary outcome measures included agreement of diagnoses and management decisions made by an ENT medical practitioner and Physiotherapist based on a vestibular physiotherapy assessment. Adverse events were reviewed 11 months post data collection. Gwet's first order agreement co-efficient (AC1) calculated inter-rater reliability between physiotherapy and ENT. Results: Fifty-one participants were recruited consecutively from the primary contact physiotherapy-led vestibular clinic. Physiotherapy and ENT had a substantial agreement (AC1 0.613) on diagnosis. AC1 between physiotherapy and ENT for recommending Magnetic resonance imaging (0.810) and computerized tomography (0.935) both indicated near perfect agreement. There was moderate to near-perfect agreement regarding management recommendations between physiotherapy and ENT. Substantial agreement (AC1 0.720) was found for recommendations for ENT input, near perfect agreement (AC1 0.933) for neurology input and moderate agreement (AC1 0.574) for physiotherapy input. There were no adverse events from physiotherapist's management decision, based on final recommendations undertaken 11-months post data collection. Conclusions: Physiotherapists and ENT medical practitioner made comparable diagnostic and management decisions, based on physiotherapy and audiology hearing assessment, for adults with signs of vestibular dysfunction, within an ENT primary contact physiotherapy-led vestibular clinic. This study provides support for this type of Physiotherapy-led service in managing patients referred to an ENT service with vestibular dysfunction. Key points: 1. This is the first study investigating interprofessional agreement between physiotherapists and an ENT medical practitioner in the diagnosis and management of patients within an ENT primary contact physiotherapy-led vestibular clinic (recommendations were based on a vestibular physiotherapy assessment as participants were not directly assessed by ENT). 2. Physiotherapists and ENT agreement on diagnosis was substantial. 3. Agreement between physiotherapy and ENT on requesting MRI brain and CT head were near perfect; and agreement between physiotherapy and ENT for onward management to ENT, neurology or physiotherapy was moderate to near perfect. 4. There were no adverse events from physiotherapy's management decision, based on the final recommendations. 5. This paper provides support for the competency of physiotherapists in managing patients referred to ENT with vestibular dysfunction and the safety of ENT primary contact physiotherapy-led vestibular clinics, albeit the presence of bias given the recommendations were based on a vestibular physiotherapy assessment only. [ABSTRACT FROM AUTHOR]

Background: Usher's syndrome type II (USH2) is a rare genetic disorder encompassing hearing loss, vision impairment, and apparent intact vestibular function. Recent research suggests a potential involvement of the otolith vestibular receptors in USH2. Aims/Objectives: Evaluate otolith dynamic function in USH2. Material and Methods: Twenty-two USH2 (median age 53.9 ± 2.99) and age-matched controls underwent a complete battery vestibular testing including air conducted cervical and ocular vestibular evoked myogenic potentials (c-VEMPs and o-VEMPs). Vestibular function tests were correlated with Activities Balance Scale (ABC) and Dizziness Handicap Inventory (DHI) scores. Results: Fourteen USH2 reported previous vertigo (vs none control). Among 88 ears, c-VEMPs were absent in 15 USH2 cases and 4 controls (p = 0.034), while o-VEMPs were absent in 22 USH2 cases and 12 controls (p = 0.129). There were significant differences between USH2 vs controls in right ear o-VEMP N1 latencies (median 11.60/10.40, p < 0.010), N1-P1 amplitudes (median 5.15/10.10, p < 0.003) and in o-VEMP N1-P1 asymmetry ratio (median 24.78/40.50, p < 0.014). USH2 showed a strong correlation between o-VEMP amplitude and DHI score (p = 0.003, ρ = 0.769). No association was found between vertigo and VEMPs subgroups. Conclusions and Significance: Our findings suggest the presence of otolith dysfunction in USH2, which is independent from subjectively reported dizziness. Incorporating vestibular testing into USH2 evaluation and monitoring could enhance characterization of this multisensory disease. [ABSTRACT FROM AUTHOR]

Background: Postural control deficits have been documented in children with autism spectrum disorder (ASD), yet vestibular system contributions to postural control have not been widely considered. The purpose of this study is to explore the relationship between functional balance, postural sway, and vestibular function in children with ASD. Methods: Ten children with a confirmed diagnosis of ASD according to DSM-V guidelines along with ten children with no known neurodevelopmental or motor delays participated in the study. Bruininks–Oseretsky Test of Motor Proficiency and the Paediatric Balance Scale measured functional balance ability, and postural sway was measured using static posturography with modified sensory inputs. Peripheral vestibular function was measured using cervical vestibular evoked myogenic potentials and video head impulse testing. Correlations between measures were performed. Results: When visual cues were removed, children with ASD demonstrated larger path velocities indicative of reduced postural control, and different patterns of postural sway. Functional balance was correlated with path velocities for conditions where sensory information was modified. No differences in peripheral vestibular function were noted between groups, and functional balance was not correlated with vestibular function. Conclusions: Findings suggest that while peripheral vestibular function is similar between groups, postural control differences in children with ASD remain, particularly for conditions where sensory information is modified. Furthermore, demonstrated patterns of postural sway suggest sensory system integration is less developed in children with ASD. These findings highlight the importance of utilising a range of clinical tools to quantify balance ability and consideration of postural control measures to inform intervention. [ABSTRACT FROM AUTHOR]

Objectives: To quantify norms and changes in eye-tracking proficiency, and determine vestibular symptom correlations in varsity college athletes following acute mild traumatic brain injury (mTBI). We hypothesized that mTBI impacts central coordination between the vestibular and oculomotor systems with resultant changes in eye-tracking proficiency that are correlated with vestibular symptom provocation. Design: Retrospective cohort study. Setting: Sports medicine care at a single institution. Patients: One hundred and nineteen college athletes diagnosed with mTBI by a physician between 2013 and 2019. Interventions: N/A. Main Outcome Measures: Standard deviation of tangential error, standard deviation of radian error, mean phase error, and horizontal gain from virtual reality-based, circular eye-tracking goggles used at baseline and within 72 hours post-mTBI. Headache, dizziness, nausea, and fogginess provocation after the Vestibular Ocular Motor Screening (VOMS) smooth pursuits subtest compared with pretest baseline, assessed within 72 hours post-mTBI. Results: One hundred and nineteen college athletes (N 5 56 women and 63 men) aged 18 to 24 years sustained a total of 177 mTBI. Forty-four percent of athletes displayed abnormal eye-tracking on at least 1 eye-tracking measure following acute mTBI compared with their baseline. From the VOMS, horizontal gain showed medium-sized to large-sized positive correlations with headache (r50.34) and dizziness (r50.54), respectively. Mean phase error showed a medium-sized negative correlation with nausea (r 5 20.32) on the VOMS. Conclusions: Eye-tracking proficiency was impaired and correlated with vestibular symptom provocation following acute mTBI in college athletes. Future research should examine eye-tracking proficiency testing in other acute care settings to support mTBI diagnosis. [ABSTRACT FROM AUTHOR]

Purpose: This review aims to investigate the effects of the Gufoni maneuver on horizontal semicircular canal benign paroxysmal positional vertigo (HC-BPPV). Methods: A comprehensive search, including PubMed, PEDro, REHABDATA, SCOPUS, EMBASE, and Web of Science, was conducted to determine randomized clinical trials (RCTs) studying the effects of the Gufoni maneuver for HC-BPPV from inception to March 1, 2024. The quality of the included studies was estimated using the Physiotherapy Evidence Database (PEDro) scale. Results: Ten randomized controlled trials (RCTs) were included in this review with a total of 1025 HC-BPPV patients (mean age = 58.58 years; 63% female; 55% right-side HC-HBPPV; 49% geotropic HC-BPPV). The included RCTs ranged from 4 to 9 out of 10 (median = 6.5) on the PEDro scale. The included studies showed that the Gufoni maneuver revealed efficacy when compared to the sham maneuver but not when compared to other maneuvers such as the Barbecue roll maneuver, the Appiani maneuver, the Mastoid oscillation, the head shaking, and the modified Gufoni maneuver. Conclusions: The Gufoni maneuver is considered an option for treating patients with geotropic or apogeotropic HC-BPPV. Precise diagnosis of the BPPV, the subtype of HC-BPPV, symptom duration, history of previous BPPV attacks, the applied methods of maneuver and the proficiency of the clinician performing the maneuver, proper diagnosis, presence of any underlying health conditions are critical for successful treatment. Further studies are strongly warranted. [ABSTRACT FROM AUTHOR]

In all vertebrates, maintaining trunk posture primarily depends on descending commands originating from brainstem vestibulospinal nuclei. Despite being broadly outlined across species, the detailed anatomical and operational structure of these vestibulospinal networks remains poorly understood. Xenopus frogs have previously served as an excellent model for exploring such anatomical and functional aspects in relation to the animal’s behavioral requirements. In this study, we examined the reflex motor reactions induced by vestibular stimulation in pre-metamorphic tadpoles. Our findings indicate that natural vestibular stimulation in the horizontal plane yields greater efficacy compared to stimulation in other planes, a phenomenon replicated in a frequencydependent manner through specific galvanic stimulation (GVS) of the horizontal semicircular canals. With the exception of a very rostral cluster of neurons that receive vestibular inputs and project to the spinal cord, the overall anatomical segregation of vestibulospinal nuclei in the brainstem mirrors that observed in juvenile frogs. However, our results suggest closer similarities to mammalian organization than previously acknowledged. Moreover, we demonstrated that vestibulospinal cells project not only to spinal motoneurons in rostral segments but also to more distal segments that undergo regression during metamorphosis. Lastly, we illustrated how vestibular-induced spinal reflexes change during larval development, transitioning from tail swim-based activity to rostral trunk bursting responses, likely anticipating postural control in post-metamorphic frogs. [ABSTRACT FROM AUTHOR]

Hearing and vestibular research in Aotearoa New Zealand (NZ) spans basic sciences, clinical research, and public health. Equitable health care and sustainable research models are threatened by several factors including the increasing prevalence of hearing impairment and vestibular disorders, reforms to the NZ public health system, and funding challenges within the research environment. Our perspectives as early career researchers can shape the future of hearing and vestibular research, healthcare, and clinical practice in NZ. [ABSTRACT FROM AUTHOR]

Blast deafness and balance disorders are common consequences of modern warfare and terrorist actions. A predictive evaluation system can assist commanders in quickly gathering information on the incapacitation of combat personnel. However, a critical challenge to this goal was to clarify the dose–response relationship between the blast parameters and the severity of auditory and vestibular dysfunction. This paper describes the algorithms for a prediction model. We performed blast experiments to obtain data on animal auditory/vestibular dysfunction under different overpressures. Peak overpressure and positive phase duration of the blast wave were obtained by pressure measurements. The severity of auditory and vestibular dysfunction was established by the auditory brainstem response test, behavioral rating, and vestibular-evoked myogenic potentials tests. Test data were analyzed using receiver operating characteristic (ROC) curves and logistic regression analysis to obtain the overpressure limits for auditory/vestibular function and logistic regression curves for severity separately. The ROC curve analysis showed that the overpressure limit for the auditory function was 32.635 kPa and the vestibular function was 96.275 kPa. Logistic regression fitted curves illustrated the dose–response relationship between the coefficient K, normalized by peak overpressure and positive phase duration, and the risk probability of auditory and vestibular disfunction. The prediction model for the risk of auditory and vestibular disfunction severity (mild/moderate/severe) has been established based on the overpressure limit and dose–response relationship. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to comprehensively review animal and human studies that explore the role of omega-3 PUFAs in maintaining the health of the auditory organ across all life stages. Methods: This narrative review involved searching Scopus, PubMed, Google Scholar, and Cochrane Library databases for relevant articles from December 1980 to July 2023. Results: some animal and human studies suggest that both deficiency and excessive intake of long-chain omega-3 PUFAs, particularly docosahexaenoic acid (DHA), can lead to auditory neural conduction impairment and reduced hearing acuity from fetal development to old age (presbycusis). These effects are likely to be dependent on the dosage. Some research indicates that an excessive intake of omega-3, rather than a deficiency, can result in nutritional toxicity and hearing impairments. Animal studies highlight the positive impact of omega-3 supplements with high DHA content in addressing hearing damage, but human research on this subject is limited. Furthermore, certain studies propose that omega-3 PUFAs may prevent or delay age-related hearing loss, with high plasma omega-3 concentration, particularly long-chain omega-3 PUFA, linked to reduced hearing loss. Additionally, consuming fish more than twice a week may be associated with a lower risk of hearing loss in adulthood, with these effects potentially influenced by age and gender. However, the majority of studies have been conducted on animals, and clinical trials are scarce. Research on the influence of omega-3 PUFAs on the peripheral and central vestibular systems remains limited. Conclusion: This article delves into the impact of omega-3 on the auditory-vestibular system, exploring its influence on neurodevelopment, protection, and treatment. It not only highlights specific research gaps but also offers valuable insights for potential future studies. [ABSTRACT FROM AUTHOR]

This single case study describes the audiological and vestibular findings of a female patient, aged 62, with diabetes mellitus and rheumatoid arthritis. Based on this case study, we hypothesize that individuals with diabetes mellitus and rheumatoid arthritis are more vulnerable to vestibular impairment. The current findings indicate that central vestibular lesions and bilateral sensorineural hearing loss are related to rheumatoid arthritis and diabetes. Therefore concluding early detection and follow-up is required to understand pathophysiology in detail. [ABSTRACT FROM AUTHOR]

In patients with cerebellar ataxia (CA), symptoms related to oculomotor dysfunction significantly affect quality of life (QoL). This study aimed to analyze the literature on patient-related outcome measures (PROMs) assessing QoL impacts of vestibular and cerebellar oculomotor abnormalities in patients with CA to identify the strengths and limitations of existing scales and highlight any areas of unmet need. A systematic review was conducted (Medline, Embase) of English-language original articles reporting on QoL measures in patients with vertigo, dizziness or CA. Pre-specified parameters were retrieved, including diseases studied, scales applied and conclusions drawn. Our search yielded 3671 articles of which 467 studies (n = 111,606 participants) were deemed relevant. The most frequently studied disease entities were (a) non-specific dizziness/gait imbalance (114 studies; 54,581 participants), (b) vestibular schwannomas (66; 15,360), and (c) vestibular disorders not further specified (66; 10,259). The Dizziness Handicap Inventory (DHI) was the most frequently used PROM to assess QoL (n = 91,851), followed by the Penn Acoustic Neuroma Quality-of-Life Scale (n = 12,027) and the Activities-Specific Balance Confidence Scale (n = 2'471). QoL-scores capturing symptoms related to oculomotor abnormalities in CA were rare, focused on visual impairments (e.g., National-Eye-Institute Visual Function Questionnaire, Oscillopsia Functional Impact, oscillopsia severity score) and were unvalidated. The DHI remains the most widely used and versatile scale for evaluating dizziness. A lack of well-established PROMs for assessing the impact of oculomotor-related symptoms on QoL in CA was noted, emphasizing the need for developing and validating a new QoL-score dedicated to the oculomotor domain for individuals with CA. [ABSTRACT FROM AUTHOR]

Because of the crucial importance of finding a useful biomarker for further clinical trials in Machado-Joseph disease (MJD), and based on our previous studies, we aimed to evaluate whether the horizontal vestibulo-ocular reflex (VOR) gain could be a reliable neurophysiological biomarker for the clinical onset, severity, and progression of the disease. Thirty-five MJD patients, 11 pre-symptomatic genetically confirmed MJD subjects, and 20 healthy controls underwent a detailed epidemiological and clinical neurological examination including the Scale for the Assessment and Rating of Ataxia (SARA). Their VOR gain was measured using the video Head Impulse Test system. Twenty of the MJD patients were re-tested after a period of 1–3 years. Horizontal VOR gain was abnormal in 92% of MJD, 54% pre-symptomatic, and 0% healthy controls. Horizontal VOR gain in the MJD group was significantly negatively correlated with SARA score in the first (r=0.66, p<0.001) and second (r=0.61, p<0.001) examinations. There was also a significant negative correlation between the percentage of change in horizontal VOR gain and the percentage of change in SARA score across both examinations (r=−0.54, p < 0.05). A regression model of the SARA score with the horizontal VOR gain and disease duration as predictors demonstrated that both the horizontal VOR gain and the disease duration had an independent contribution to the prediction of the SARA score. The horizontal VOR gain seems to be a reliable biomarker for the clinical onset, severity, and progression of MJD and could be used in further clinical studies. [ABSTRACT FROM AUTHOR]

Patients with persistent postural-perceptual dizziness (PPPD) perceive postural instability larger than the observed sway. It is unknown whether the concept of postural misperception prevails during vestibular stimulation and whether it may account for the unsteadiness patients complain during body movements. We tested the hypothesis of an abnormal sensory-perceptual scaling mechanism in PPPD by recording objective, perceived, and the reproduced postural sway under various standing conditions, modulating visual and proprioceptive input, by binaural galvanic vestibular stimulation (GVS). We related postural sway speed to individual vestibular motion perceptional thresholds and disease-related PPPD questionnaires in 32 patients and 28 age-matched healthy control subjects (HC). All participants showed normal vestibular function tests on quantitative testing at the time of enrollment. The perception threshold of GVS was lower in patients. Compared to HC, patients showed and perceived larger sway on the firm platform. With GVS, posturo-perceptual ratios did not show group differences. The ratio of reproduced to real postural sway showed no group differences indicating normal postural sway perception during vestibular stimulation. Noticeably, only in patients, reproduced postural instability became larger with lower individual thresholds of vestibular motion detection. We conclude that posturo-perceptual (metacognitive) scaling of postural control seems to be largely preserved in PPPD during GVS. Vestibular stimulation does not destabilize patients more than HC, even in challenging postural conditions. Low individual thresholds of vestibular motion perception seem to facilitate instability and postural misperception on solid grounds. This conclusion is important for an effective physical therapy with vestibular exercises in PPPD. [ABSTRACT FROM AUTHOR]

Background: The ototoxicity of both chemotherapy and radiotherapy has been studied. Little is known regarding their impact on the vestibular system, particularly, the laboratory vestibular testing that evaluates the effects of both chemotherapy and radiotherapy on the peripheral and central vestibular system. Consequently, the current research was designed to study Videonystagmography (VNG) and video head impulse test (vHIT)in patients with head and neck cancer receiving chemotherapy and radiotherapy for early diagnosis of vestibularsystem abnormalities. Methods: This study included two groups with head and neck cancer: group I included 19 patients receiving chemotherapy and group II included 19 patients receiving radiotherapy. Basic audiological evaluation, VNG, and vHIT were conducted on all patients before treatment and 3 months following treatment. Results: Regarding pure tone audiometry, there was a statistically significant increase in hearing threshold at high frequencies in patients receiving chemotherapy and radiotherapy before and after treatment. As regards the VNG test, there was a statistically significant impairment in saccade, smooth pursuit, optokinetic, and caloric tests in patients before and after receiving chemotherapy. However, in patients receiving radiotherapy, there was no statistically significant difference in the VNG test battery except for increased value of caloric weakness. vHIT abnormalities were reported in patients of both groups. Conclusions: This study demonstrated the ototoxic and vestibulotoxic effects of both chemotherapy and radiotherapy in patients with head and neck cancer. [ABSTRACT FROM AUTHOR]

Audiovestibular dysfunction in patients with systemic lupus erythematosus has been underestimated for decades. Systemic lupus erythematosus can affect both the auditory and vestibular systems simultaneously. Several potential pathophysiological mechanisms behind systemic lupus erythematosus-related audiovestibular dysfunction have been proposed, including antibody-mediated immune responses, cell-mediated cytotoxicity, immune complex deposition in microvessels, central involvement in the audiovestibular pathway, and ototoxicity from medications used in systemic lupus erythematosus treatment. Currently available tests to evaluate audiovestibular function in systemic lupus erythematosus patients are neither specific nor sensitive. Nevertheless, there is no consensus regarding the efficacy of treatments for audiovestibular dysfunction in such patients. In this systematic review, we electronically searched the PubMed, Embase, ClinicalKey, Web of Science, and ScienceDirect platforms to find eligible articles. The first inspection date was on 29 December 2023 and the final update search date was on 11 June 2024. Further, we rated the quality of the included articles with Newcastle–Ottawa Scale. Based upon the aforementioned systematic review process, we have summarized the currently available evidence on the characteristics, pathophysiology, examination, and treatment of audiovestibular dysfunction related to systemic lupus erythematosus. Furthermore, we have proposed a specific steroid treatment protocol to manage audiovestibular dysfunction related to systemic lupus erythematosus. Audiovestibular dysfunction related to systemic lupus erythematosus may be responsive to adequate treatments, potentially allowing for reversibility if the disease is recognized and managed in a timely manner. Therefore, to provide clinically relevant evidence to clinicians, we have organized this literature review article to summarize the available evidence on the characteristics, pathophysiology, examination, and treatment of audiovestibular dysfunction in patients with systemic lupus erythematosus. Finally, based on our modified steroid treatment protocol, we would like to provide a new treatment strategy to clinicians to manage systemic lupus erythematosus-related audiovestibular dysfunction. [ABSTRACT FROM AUTHOR]

The relative contributions of proprioceptive, vestibular, and visual sensory cues to balance control change depending on their availability and reliability. This sensory reweighting is classically supported by nonlinear sway responses to increasing visual surround and/or surface tilt amplitudes. However, recent evidence indicates that visual cues are reweighted based on visual tilt velocity rather than tilt amplitude. Therefore, we designed a study to specifically test the hypothesized velocity dependence of reweighting while expanding on earlier findings for visual reweighting by testing proprioceptive reweighting for standing balance on a tilting surface. Twenty healthy young adults stood with their eyes closed on a toes-up/-down tilting platform. We designed four pseudorandom tilt sequences with either a slow (S) or a fast (F) tilt velocity and different peak-to-peak amplitudes. We used model-based interpretations of measured sway characteristics to estimate the proprioceptive sensory weight (Wprop) within each trial. In addition, root-mean-square values of measured body center of mass sway amplitude (RMS) and velocity (RMSv) were calculated for each tilt sequence. Wprop, RMS, and RMSv values varied depending on the stimulus velocity, exhibiting large effects (all Cohen's d >1.10). In contrast, we observed no significant differences across stimulus amplitudes for Wprop (Cohen's d: 0.02–0.16) and, compared with the differences in velocity, there were much smaller changes in RMS and RMSv values (Cohen's d: 0.05–0.91). These results confirmed the hypothesized velocity, rather than amplitude, dependence of sensory reweighting. NEW & NOTEWORTHY: This novel study examined the velocity dependence of sensory reweighting for human balance control using support surface tilt stimuli with independently varied amplitude and velocity. Estimates of the proprioceptive contribution to standing balance, derived from model-based interpretations of sway characteristics, showed greater sensitivity to changes in surface tilt velocity than surface tilt amplitude. These results support a velocity-based mechanism underlying sensory reweighting for human balance control. [ABSTRACT FROM AUTHOR]

Everyday actions like moving the head, walking around, and grasping objects are typically self-controlled. This presents a problem when studying the signals encoding such actions because active self-movement is difficult to control experimentally. Available techniques demand repeatable trials, but each action is unique, making it difficult to measure fundamental properties like psychophysical thresholds. We present a novel paradigm that recovers both precision and bias of self-movement signals with minimal constraint on the participant. The paradigm relies on linking image motion to previous self-movement, and two experimental phases to extract the signal encoding the latter. The paradigm takes care of a hidden source of external noise not previously accounted for in techniques that link display motion to self-movement in real time (e.g., virtual reality). We use head rotations as an example of self-movement, and show that the precision of the signals encoding head movement depends on whether they are being used to judge visual motion or auditory motion. We find that perceived motion is slowed during head movement in both cases. The "nonimage" signals encoding active head rotation (motor commands, proprioception, and vestibular cues) are therefore biased toward lower speeds and/or displacements. In a second experiment, we trained participants to rotate their heads at different rates and found that the imprecision of the head rotation signal rises proportionally with head speed (Weber's law). We discuss the findings in terms of the different motion cues used by vision and hearing, and the implications they have for Bayesian models of motion perception. NEW & NOTEWORTHY: We present a psychophysical technique for measuring the precision of signals encoding active self-movements. Using head movements, we show that 1) precision is greater when active head rotation is performed using visual comparison stimuli versus auditory; 2) precision decreases with head speed (Weber's law); 3) perceived speed is lower during head rotation. The findings may reflect the steps needed to convert different cues into common units, and challenge standard Bayesian models of motion perception. [ABSTRACT FROM AUTHOR]

The present study explored the presence of torsional gaze-stabilization to proprioceptive neck activation in humans. Thirteen healthy subjects (6 female, mean age 25) were exposed to passive body rotations while maintaining a head-fixed, gravitationally upright, position. Participants were seated in a mechanical sled, their heads placed in a chin rest embedded in a wooden beam while wearing an eye tracker attached to the beam using strong rubber bands to ensure head stability. The body was passively rotated underneath the head both in darkness and while viewing a projected visual scene. Static torsional gaze positions were compared between the baseline position prior to the stimulation, and immediately after the final body tilt had been reached. Results showed that passive neck flexion produced ocular torsion when combined with a visual background. The eyes exhibited rotations in the opposite direction of the neck's extension, matching a hypothetical head tilt in the same direction as the sled. This corresponded with a predicted head rotation aimed at straightening the head in relation to the body. No such response was seen during trials in darkness. Altogether, these findings suggest that proprioception may produce a predictive gaze-stabilizing response in humans. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to provide a comprehensive understanding of the spatial orientation of the crista ampullaris within the inner ear and its implications for the diagnosis and management of benign paroxysmal positional vertigo (BPPV). Methods: Using high-resolutionMRI scans of 55 normal inner ears, 3Dmodels of the semicircular canals were segmented. These were complemented by detailed membrane labyrinth models from micro-CT scans of human temporal bones, accessed via the Comparative Ear Bank (www.earbank.org). A statistical shape model of inner ears and eyeballs was established, and a standardized 3D spatial coordinate system was created. The horizontal plane was defined using the top of the common crus and the bottom of the eyeballs. This calibrated reference system allowed for precise quantification of crista ampullaris orientations by calculating angles between the defined crista planes and coordinate planes. Results: The plane of the ampulla and the corresponding semicircular canal plane are nearly perpendicular to each other. In the upright position, the posterior semicircular canal crista ampullaris formed an angle of 48.9? with the horizontal plane. The relative orientations of the crista ampullaris of the lateral and superior canals were also defined. Furthermore, we identified "zero-point planes" representing crista orientations perpendicular to gravity, which resulted in minimal ampullary stimulation. A 6.2? tilt to the left in the supine position resulted in the plane of the left lateral semicircular canal crista ampullaris being parallel to the direction of gravity. Conclusion: This study elucidates the precise spatial orientation of the crista ampullaris, thereby providing an anatomical basis for understanding BPPV pathophysiology and improving the accuracy of diagnostic and therapeutic maneuvers. The findings have the potential to significantly enhance the management of BPPV and other inner ear disorders. [ABSTRACT FROM AUTHOR]

Introduction and objective: The association of vestibular symptoms in patients with migraine is more frequent than in the general population. In childhood, one of the most common causes of dizziness is vestibular migraine, which due to its variety of symptoms is often the object of study by various specialties. The purpose of this article is to perform a bibliographic review that allows us to familiarize ourselves with this pathology. Method: A bibliographic review of the articles published in the main databases ((PubMed) Medline, UpToDate, Elsevier, Cochrane Library, Science Direct) was conducted, selecting the most relevant articles according to type of study and year of publication. Results: Vestibular migraine is a diagnosis to consider in the evaluation of the pediatric patient, given its prevalence and the spectrum of differential diagnosis to which it belongs. Discussion: Vestibular migraine in childhood has an unknown prevalence and is defined by the presence of headache with migraine characteristics, accompanied by vestibular symptoms, before, during or after the migraine attack. Its diagnosis is made using the new diagnostic criteria published by the ICVD (International Classification of Vestibular Disorders) in 2021 and does not require other tests for its diagnosis. So far, there is no specific treatment, and the existing one is based on the control of the symptoms of the migraine attack. Conclusions: One of the most frequent causes of dizziness in children is vestibular migraine, which, as of 2021, has its own diagnostic criteria, together with a spectrum of diseases with which a differential diagnosis must be made. Despite the studies conducted, there is no standardized treatment for this pathology. [ABSTRACT FROM AUTHOR]

We investigated the extent of literature and findings on relationships between vestibular issues, noise sensitivity (NS), and anxiety. We were interested in how relationships among these factors impacted adults' recovery three months or more after mild traumatic brain injury (mTBI). We conducted a scoping review to evaluate the extent of evidence linking relationships between vestibular issues, NS and anxiety with recovery after mTBI. Data relating to study characteristics and key findings were extracted and used to inform a critical narrative synthesis of findings. After screening and full-text review, we included two studies. Both studies considered the combination of vestibular issues, NS and anxiety and mTBI recovery. Vestibular issues, NS and anxiety were all significantly associated with one another and their presence was the strongest indicator that symptoms would extend beyond three-months after mTBI. Few studies have focused on the relationships that vestibular issues, NS and anxiety have with one another and recovery after mTBI. Given the apparent strong relationships between these factors and prolonged recovery, we highlight this as an area warranting further investigation. Vestibular issues, noise sensitivity and anxiety all appear to impact on recovery from mild traumatic brain injury. There appear to be quite strong relationships between vestibular, noise sensitivity and anxiety symptoms following mild traumatic brain injury. More work exploring these key symptoms and how they impact recovery from mild traumatic brain injury using a wide range of study methods and approaches are needed to advance the field. [ABSTRACT FROM AUTHOR]

Background Subjective unsteadiness or dizziness, usually without increase in body sway, is common in older people. The absence of mechanistic understanding of such symptoms renders clinical management difficult. Here, we explore the mechanisms behind such idiopathic dizziness (ID), focusing on postural control abnormalities. Methods Thirty patients with ID and 30 age-matched controls stood on a moving platform. Platform oscillations were randomly delivered at different velocities (from 0 to 0.2 m/s). Markers of postural control, including objective sway (trunk sway path, recorded via a sensor attached to vertebrae C7), stepping responses, subjective instability and anxiety ratings were obtained. MRI scans were available for correlations with levels of cerebral small vessel disease in 28 patients and 24 controls. Results We observed a significant relationship between objective and subjective instability in all groups. The slope of this fit was significantly steeper for patients than controls, indicating greater perceived instability for the same body sway. Stepwise linear regression showed that the slopes of this objective–subjective instability relationship were best explained by concerns about falling (Falls Efficacy Scale-International), clinical physical functioning (Short Physical Performance Battery) and, to some degree, by neuroimaging markers of cerebral small vessel disease. In addition, patients had a reduced stepping threshold, suggesting an overly cautious postural response. Conclusion The distorted perception of instability and subtle impairments in balance control, including abnormal and overly cautious stepping responses, underlies the emergence of ID. It appears to relate to changes in postural performance, psychological functioning and disruption of postural brain networks associated with cerebral small vessel disease. [ABSTRACT FROM AUTHOR]