Binocular video head impulse test: Normative data study.

Introduction: The video head impulse test (vHIT) evaluates the vestibulo-ocular reflex (VOR). It's usually recorded from only one eye. Newer vHIT devices allow a binocular quantification of the VOR. Purpose Aim: To investigate the advantages of simultaneously recorded binocular vHIT (bvHIT) to detect the differences between the VOR gains of the adducting and the abducting eye, to define the most precise VOR measure, and to assess gaze dys/conjugacy. We aimed to establish normative values for bvHIT adducting/abducting eye VOR gains and to introduce the VOR dysconjugacy ratio (vorDR) between adducting and abducting eyes for bvHIT. Methods: We enrolled 44 healthy adult participants in a cross-sectional, prospective study using a repeated-measures design to assess test-retest reliability. A binocular EyeSeeCam Sci 2 device was used to simultaneously record bvHIT from both eyes during impulsive head stimulation in the horizontal plane. Results: Pooled bvHIT retest gains of the adducting eye significantly exceeded those of the abducting eye (mean (SD): 1.08 (SD = 0.06), 0.95 (SD = 0.06), respectively). Both adduction and abduction gains showed similar variability, suggesting comparable precision and therefore equal suitability for VOR asymmetry assessment. The pooled vorDR here introduced to bvHIT was 1.13 (SD = 0.05). The test-retest repeatability coefficient was 0.06. Conclusion: Our study provides normative values reflecting the conjugacy of eye movement responses to horizontal bvHIT in healthy participants. The results were similar to a previous study using the gold-standard scleral search coil, which also reported greater VOR gains in the adducting than in the abducting eye. In analogy to the analysis of saccade conjugacy, we propose the use of a novel bvHIT dysconjugacy ratio to assess dys/conjugacy of VOR-induced eye movements. In addition, to accurately assess VOR asymmetry, and to avoid directional gain preponderance between adduction and abduction VOR-induced eye movements leading to monocular vHIT bias, we recommend using a binocular ductional VOR asymmetry index that compares the VOR gains of only the abduction or only the adduction movements of both eyes.

Assessment of vestibulo-ocular reflex and its adaptation during stop-and-go car rides in motion sickness susceptible passengers.

Motion sickness is a physiological condition that negatively impacts a person's comfort and will be an emerging condition in autonomous vehicles without proper countermeasures. The vestibular system plays a key role in the origin of motion sickness. Understanding the susceptibility and (mal) adaptive mechanisms of the highly integrated vestibular system is a prerequisite for the development of countermeasures. We hypothesize a differential association between motion sickness and vestibular function in healthy individuals with and without susceptibility for motion sickness. We quantified vestibular function by measuring the high-frequency vestibulo-ocular reflex (VOR) using video head impulse testing (vHIT) in 17 healthy volunteers before and after a 11 min motion sickness-inducing naturalistic stop-and-go car ride on a test track (Dekra Test Oval, Klettwitz, Germany). The cohort was classified as motion sickness susceptible (n = 11) and non-susceptible (n = 6). Six (out of 11) susceptible participants developed nausea symptoms, while a total of nine participants were free of these symptoms. The VOR gain (1) did not differ significantly between participant groups with (n = 8) and without motion sickness symptoms (n = 9), (2) did not differ significantly in the factor time before and after the car ride, and showed no interaction between symptom groups and time, as indicated by a repeated measures ANOVA (F(1,15) = 2.19, p = 0.16. Bayesian inference confirmed that there was "anecdotal evidence" for equality of gain rather than difference across groups and time (BF10 < 0.77). Our results suggest that individual differences in VOR measures or adaptation to motion sickness provocative stimuli during naturalistic stop-and-go driving cannot predict motion sickness susceptibility or the likelihood of developing motion sickness.

[Optimization of long-term care of neurological patients through internet- and mobile-based interventions with and without persuasive elements including gamification]. / Optimierung der Langzeitbetreuung von neurologischen Patienten durch internet- und mobile-basierte Interventionen ohne und mit persuasiven Elementen einschließlich der Gamification.

In a pilot study of 60 neurological long-term patients (degenerative cerebral microangiopathy with reduced sensorimotor stability), an initial assessment of the practicability of a specially developed concept was carried out focusing on the communication aspect of long-term medical treatment. Patient preferences, methods for increasing the patient's own activity and other factors determining adherence were analysed and optimised. In addition to communication and factual arguments, an affective-emotional, multi-layered message transmission is required, which adapts comprehensively and in real time to the recipient. Persuasion is the targeted addressing of behavioural patterns. Gamification transfers playful elements into a game-free context. Technology-based approaches offer an opportunity to optimize aspects of health, quality of life and positive disease management, e. g. through the use of internet- and mobile-based interventions (IMIs). Based on this information-theoretical and health-communicative background, a pilot study was conducted with 60 neurological long-term patients with symptomatic cerebral microangiopathy patients hospitalised for an existing sensorimotor incompetence. During the one-week inpatient stay, patients received an introduction to a standardized sensorimotor training therapy, which they then continued for six weeks after being discharged as a four-arm intervention study on an outpatient basis on the clinic campus or at home, each without and with gamification. Patients were examined at the beginning and end of the training phase with motor-functional procedures and test psychology. Thereafter, they were subjected to a standardised guideline interview. The most important results were as follows:- The training therapy was effective and was accepted by the patients. They attached particular importance to: high user-friendliness, high precision in reflecting their level of control of even subtle training elements, and personal progress evaluation in real time.- The domestic training results were better than those of the ambulance campus.- A comparison of the individual groups showed almost consistently better results under gamification, both at home and on an outpatient basis.