Effect of Video Games on the Otolithic Reflex System

<b><i>Background:</i></b> Video gaming (VG) has since the 1980s become increasingly ubiquitous entertainment among the adolescents and young adults. Many young people expe­rienced dizzy spells, but not vertiginous episodes, after playing VG. <b><i>Objectives:</i></b> This study performed ocular vestibular-evoked myogenic potential (oVEMP) and cervical VEMP (cVEMP) tests in subjects before and after engaging on VG to investigate the effect of VG on the otolithic reflex system. <b><i>Methods:</i></b> Twenty subjects who frequently played VG (&#x3e;3 days per week) for more than 10 years were assigned to the long-term group. Another 20 subjects with engaging on VG &#x3c;3 days per week or &#x3c;10 years were assigned to the short-term group. Each subject underwent baseline oVEMP and cVEMP tests first, followed by playing VG for 1 h. Then, all subjects underwent the same paradigm. The “VG-year” is defined as frequency of VG playing within 1 week (day/week) multiplied by total length of VG engagement (year). <b><i>Results:</i></b> Engagement on VG rarely affected the oVEMP responses for either short- or long-term players. In contrast, the response rates of cVEMP significantly declined from pre-VG period (80%) to post-VG period (58%) in the short-term group, but not in the long-term group. The cutoff value for predicting absent cVEMP in VG engagement is 21 VG-year. <b><i>Conclusion:</i></b> Short-term engagement on VG may result in temporary cVEMP loss, while permanent cVEMP loss could be identified in long-term VG players. The cutoff value for predicting absent cVEMP in VG engagement is 21 VG-year, indicating that damage to the sacculo-collic reflex system could be anticipated in a subject who has played VG at least 1 h per session, 7 days weekly for 3 years.

Parameters of Off-Vertical Axis Rotation in Unilateral and Bilateral Vestibulopathy and Their Correlation with Vestibular Evoked Myogenic Potentials

Off-vertical axis rotation (OVAR) is a laboratory test to assess the otolith function. This study aimed to analyze the parameters of OVAR in patients with unilateral vestibular hypofunction (UVH) and bilateral vestibulopathy (BVP), and to correlate the parameters of OVAR with those of VEMPs. Ten healthy volunteers, 41 UVH, and 13 BVP patients performed OVAR. Bias component (BIC) and modulation component (MOC) of UVH and BVP patients were compared with those of healthy controls. BIC and MOC were correlated with amplitude and interaural difference (IAD) of cervical VEMP (cVEMP) and ocular VEMP (oVEMP). In UVH patients, the direction of BICs to affected side rotation were reversed and the absolute value of BICs were decreased when they were compared to healthy controls. In BVP patients, BICs were markedly attenuated. MOCs were not changed in UVH and BVP patients. There was no statistically significant correlation between VEMPs and OVAR.

Assessment of cervical and ocular vestibular evoked myogenic potentials in migraine patients

Background Patients suffering from vestibular migraine (VM) are known to have various vestibular test abnormalities interictally and ictally. Recently, vestibular evoked myogenic potentials (VEMPs) have become accepted as a valid method for otolith function assessment. Many studies have identified various vestibular symptoms and laboratory abnormalities in migraineurs. Since migraineurs with no accompanying vestibular symptoms might exhibit subclinical vestibular dysfunction, we investigated vestibular function using ocular and cervical VEMPs in migraine patients. The aim was to study cervical VEMP and occular VEMP in migraineurs with and without vestibular symptoms interictally. Results Migraine and VM patients showed significantly longer P13 latency of cVEMP compared to controls. A statistically significant cVEMP interaural P13 latency difference was found in VM compared to healthy controls. Cervical VEMP N23 latency, peak-to-peak amplitude, interaural N23 latency, and amplitude asymmetric ratio did not show any significant difference in migraine and VM patients compared to healthy controls as well as no significant difference across the three groups regarding oVEMP parameters. Conclusions Abnormal interictal cVEMP results in migraineurs might indicate subclinical vestibulo-collic pathway dysfunction.

Diagnostic capabilities of the vestibular evoked myogenic potential test in children with vestibular dysfunction

<p class="abstract"><strong>Background:</strong> Vestibular evoked myogenic potential (VEMP) testing is used in the diagnosis of vestibular disorders. It is an objective method for testing the the otolith organs of the vestibular system. VEMP test is an additional method for diagnosing vestibular neuritis (VN). The combination of cervical VEMP (cVEMP) and ocular VEMP (oVEMP) testing has an advantage in long-term monitoring of patients with VN. The VEMP test is well-studied for adults but studies involving children are insufficient. The aim of this study was to analysis and evaluation of the results from VEMP testing of children diagnosed with vestibular dysfunction. Analysis and evaluation of the results from VEMP testing of children diagnosed with vestibular dysfunction.</p><p class="abstract"><strong>Methods:</strong> History, examination of ENT organs, tone threshold audiometry, tympanometry, otoneurological examination, VEMP test. </p><p class="abstract"><strong>Results:</strong> Children with vestibular dysfunction who were examined showed changes predominantly in the oVEMP test. The upper branch of the vestibular nerve is affected. </p><p class="abstract"><strong>Conclusions:</strong> The VEMP test is an additional method for diagnosing patients with vestibular dysfunction. It is safe when used for children.</p>

Investigating short latency subcortical vestibular projections in humans: what have we learned?

Vestibular evoked myogenic potentials (VEMPs) are now widely used for the noninvasive assessment of vestibular function and diagnosis in humans. This review focuses on the origin, properties, and mechanisms of cervical VEMPs and ocular VEMPs; how these reflexes relate to reports of vestibular projections to brain stem and cervical targets; and the physiological role of (otolithic) cervical and ocular reflexes. The evidence suggests that both VEMPs are likely to represent the effects of excitation of irregularly firing otolith afferents. While the air-conducted cervical VEMP appears to mainly arise from excitation of saccular receptors, the ocular VEMP evoked by bone-conducted stimulation, including impulsive bone-conducted stimuli, mainly arises from utricular afferents. The surface responses are generated by brief changes in motor unit firing. The effects that have been demonstrated are likely to represent otolith-dependent vestibulocollic and vestibulo-ocular reflexes, both linear and torsional. These observations add to previous reports of short latency otolith projections to the target muscles in the neck (sternocleidomastoid and splenius) and extraocular muscles (the inferior oblique). New insights have been provided by the investigation and application of these techniques.

Ocular vestibular evoked myogenic potential (VEMP) reveals subcortical HTLV-1-associated neurological disease

IntroductionVestibular Myogenic Evoked Potential (VEMP) evaluates vestibulo-ocular and vestibulospinal reflexes associated with posture.PurposeTo compare cervical and ocular VEMP in individuals with HTLV-1 associated myelopathy (HAM) and with HTLV-1-asymptomatic infection.Materials and MethodsThis cross-sectional study included 52 HTLV-1-infected individuals (26 HAM and 26 asymptomatic carriers) and 26 negative controls. The groups were similar regarding age and gender. Participants underwent ocular and cervical VEMP that were performed simultaneously. The stimulus used to generate VEMP was a sound, low-frequency toneburst, intensity of 120 decibels normalized hearing level (dB nHL), bandpass filter from 10 to 1,500 Hz, with 100 stimuli at 500 Hertz (Hz) and 50 milliseconds (ms) recording time. An alteration in the electrophysiological waves P13 and N23 for cervical VEMP and N10 and P15 waves for ocular VEMP was compared between groups.ResultsCervical VEMP was different among the groups for P13 (p=0.001) and N23 (p=0.003). Ocular VEMP was similar for N10 (p=0.375) and different for P15 (p=0.000). In the HTLV-1-asymptomatic group, 1(3.8%) individual presented changes in both ocular and cervical VEMP, while in HAM group, 16(61.5%) presented changes in both tests.ConclusionNeurological impairment in HAM was not restricted to the spinal cord. The mesencephalic and thalamic connections, tested by ocular VEMP, were also altered. Damage of the oculomotor system, responsible for eye stabilization during head and body movements, may explain why dizziness is such a frequent complaint in HAM.Authors’ summaryHuman T-cell lymphotropic virus type 1 (HTLV-1) infection is endemic in Brazil and can cause HTLV-1-associated myelopathy (HAM). This neurological disease progresses slowly and, within ten years after its onset, can confine the patient to a wheelchair. Changes in HAM inflammatory characteristics can subsequently occur in the cortex, subcortical white matter, cerebellum, and brainstem. In the present study, we used the electrophysiological test Vestibular Myogenic Evoked Potential (VEMP) to evaluate the thalamic, brainstem, and spinal neural connections. This test evaluates the peripheral and the central vestibular pathway and has been used to test the postural reflexes involved in the control of one’s balance. The VEMP from the oculomotor muscles demonstrated that a subcortical impairment occurs in HAM and can also occur in the asymptomatic phase of HTLV-1 infection.

Quantitative Vestibular Function Testing in the Pediatric Population

Quantitative tests of vestibular function include the caloric test, cervical and ocular vestibular evoked myogenic potential (VEMP), rotary chair, and head impulse test, either at the bedside or utilizing video head impulse test (vHIT). The purpose of this article is to provide an overview of how to perform these tests in children, including which tests are recommended based on the child's age and any modifications or considerations that can be made. A variety of clinical measures have been recommended as screening measures for vestibular loss, which will be reviewed. Symptom questionnaires designed to assess the functional impact of dizziness and vestibular loss in children will also be discussed. If a child complains of dizziness or if vestibular loss is suspected (either by case history or positive screening measure), vestibular function testing is warranted. For vestibular function testing, children aged 0 to 2 years typically receive rotary chair, cervical VEMP, and vHIT if a remote system is available. For children aged 3 to 7 years, vHIT, cervical VEMP, and ocular VEMP are completed, and for children aged 8+ years, vHIT, caloric testing if vHIT is normal, and cervical and ocular VEMP are completed. For all children, modifications to testing can be made, as needed.

Evaluation of Vestibular Functions in Patients with Vogt-Koyanagi-Harada Disease

Vogt-Koyanagi-Harada (VKH) disease is an idiopathic, multisystem autoimmune disorder characterized by bilateral, diffuse granulomatous uveitis associated with neurological, audiovestibular, and dermatological manifestations. The purpose of this study is to investigate vestibular functions in patients with VKH disease. A total of 43 patients with VKH disease in Hokkaido University Hospital were enrolled in this study. Subjective symptoms such as dizziness or vertigo and the results of various vestibular examinations including nystagmus testing, caloric testing, and vestibular-evoked myogenic potential (VEMP) testing were investigated. Eight of 42 patients (19.0%) complained of subjective vestibular symptoms. On the other hand, 12 of 28 patients (42.9%) showed nystagmus, and 7 of 15 patients (46.7%) showed unilateral or bilateral weakness in the caloric test. VEMP testing was performed for 16 patients. Seven (43.8%) and 8 (50.0%) patients were evaluated as abnormal in cervical VEMP and ocular VEMP testing, respectively. The rate of detection of nystagmus was significantly higher than that of subjective symptoms. As vestibular dysfunction in patients with VKH disease cannot be detected through history taking alone, nystagmus testing, caloric testing, and VEMP testing should be performed to evaluate vestibular functions associated with VKH disease. It is considered that abnormal VEMP findings are associated with otolith organ dysfunction.