Motion sickness: current concepts and management

Functional and imaging anomalies of the vestibular system in motion sickness: a clinical observation study

OBJECTIVE

The aim of this study is to investigate the differences in vestibular organ function tests and the temporal bone computed tomography (CT) findings between healthy individuals and patients with motion sickness (MS), providing a basis for establishing functional and imaging diagnostic criteria for MS.

METHOD

Vestibular organ function tests and temporal bone CT imaging were performed on patients in the MS group (n = 50) and healthy individuals in the control group (n = 50). Functional and imaging anomalies of the vestibular organ were identified and their features and patterns were analyzed. Patients with MS were further stratified based on severity to examine whether temporal bone CT findings varied across severity grade, and indexes of diagnostic significance were identified.

RESULTS

Comparisons of vestibular function tests revealed significantly lower bilateral vestibular evoked myogenic potential (VEMP) amplitudes in the MS group compared to the control group, with statistical significance (P < 0.05). The severity of MS demonstrated a positive correlation with reductions in bilateral cervical VEMP (cVEMP) amplitudes (P < 0.05). Video head impulse test (v-HIT) results indicated statistically significant differences in the gains of the left anterior, right horizontal, and left posterior semicircular canals (P < 0.05). There were significant differences in the bilateral vestibular caloric test (CT) values (P < 0.05). In terms of the temporal bone CT findings in the two groups, the detection rate of high jugular bulb combined with sinusitis, poor mastoid pneumatization, diploetic mastoid, or sclerotic mastoid was higher in patients with MS than in the healthy control group. Additionally, the detection rate of temporal bone anomalies in CT scans was significantly higher in the very severe and severe MS groups compared to the mild and moderate MS groups.

CONCLUSION

In this study, we found that patients with MS exhibited functional and structural anomalies in vestibular function and temporal bone CT findings, which were correlated with the severity of MS. These findings suggest that vestibular function tests and temporal bone CT imaging can be used as objective reference indexes for the diagnosis of MS and assessment of its severity.

Early cortical processing of coherent vs. non-coherent motion stimuli in younger and older adults: An event-related potential (ERP) study investigating visually induced vection

The neurophysiological basis of vection (i.e., the illusion of self-motion) is not well understood. Preliminary evidence suggests that neural predictors of vection can be identified through event-related potentials (ERPs) and that these markers may correlate with vection intensity. The current study examined age-related differences in neurocortical activity during the early stages of sensory processing of vection-inducing stimuli. Twenty-two younger (age range: 20-35 years) and 25 older adults (age range: 65-83) observed optokinetic stimuli in two blocks, a short (∼3s) presentation block and a long (35s) presentation block. In both types of blocks, the optokinetic stimuli varied in motion coherence (coherent vs. non-coherent motion). During the short presentation block, EEG was used to measure neural activity in the form of ERPs time-locked to the onset of visual motion, whereas subjective ratings of vection intensity, duration, and onset latency were collected during the long presentation block. Vection was significantly stronger following coherent vs. non-coherent motion for both age groups. ERP analyses revealed differences between coherent and non-coherent motion at parietal-occipital electrodes around 100-150 ms (P1) and 150-230 ms (P2), with greater area under the curve (AUC) during non-coherent vs. coherent motion. Neither vection ratings nor ERPs showed significant age differences for coherent visual motion; however, age differences in ERPs were observed during the processing of non-coherent visual motion. These findings indicate that the subjective experience of vection and the neurophysiological mechanisms underlying visual processing preceding vection remain relatively stable with age. However, they also reveal age-related differences in the processing of non-coherent motion.

Choosing a drug to treat motion sickness

ABSTRACT

Patients who suffer from motion sickness despite avoiding triggers and using behavioral modifications may benefit from individualized recommendations for pharmacologic therapy. Patients with refractory motion sickness can benefit from prophylactic drug therapy using first-generation antihistamines or scopolamine.

Effects of two kinds of vestibular function training on reducing motion sickness in college students

Introduction

To explore the advantages and disadvantages of different vestibular function training to improve Motion sickness (MS) can be associated with significant symptoms, including fatigue, dizziness, headaches, nausea, and vomiting. Vestibular function training has increasingly replaced MS medications over the past few years and has almost no side effects.

Methods

We selected 109 students with MS from a university in Tangshan, China, and randomly assigned them to either an electric rotating chair group or a visual-motion cage rotating chair group. Both training groups underwent vestibular function training for 90 seconds a day for seven consecutive days.

Results

After training, both groups' Graybiel scores, blood pressure, high-frequency power (HF), and root mean square of successive differences (rMSSD) between adjacent normal heartbeats significantly decreased. In the visual-motion cage rotating chair group, in addition to a reduction in the percentage of adjacent normal-to-normal intervals which differed by more than 50 ms (pNN50), as well as decreases in low-frequency power (LF), an increase in LF/HF was observed. Between-group comparisons showed that the Graybiel scores in the electric rotating chair group were better than those in the visual-motion cage rotating chair group. When the two groups were stratified into high and low-susceptibility subgroups, the low-susceptibility subgroup of the electric rotating chair group had lower Graybiel scores and diastolic blood pressures than the low-susceptibility visual-motion cage rotating chair subgroup, whereas in the high susceptibility subgroup, LF, rMSSD, and pNN50 were significantly higher in the visual-motion cage rotating chair group than in the electric rotating chair group.

Discussion

This study compared the effects of two types of vestibular function training on Graybiel scores and heart rate variability (HRV). we found that seven days of training with both the electric rotating chair and the visual-motion cage rotating chair relieved MS symptoms and enhanced sympathetic regulation. In terms of improving the subjective degree of MS, the electric rotating chair was superior to the visual-motion cage rotating chair. Subgroup analysis results showed that low-susceptibility MS patients' symptoms were better relieved with electric rotating chair training, while high-susceptibility patients' symptoms were better relieved with visual-motion cage rotating chair training.

Formulation development and evaluation of push-pull osmotic pump bi-layered tablets for phencynonate HCl in the treatment of motion sickness

The aim of this study was to develop and evaluate an extended-release (ER) push-pull osmotic pump (PPOP) tablet for phencynonate HCl (PCN), which could release the drug at zero-order profile for a duration of 24 h. The core tablets were designed as bi-layered, primarily composed of sodium chloride and polyethylene oxide (PEO). The central composite design (CCD) within a response surface methodology (RSM) was used to optimize the formulation. An optimized PCN-PPOP tablet formulation was achieved with the following values for key factors: 10 mg NaCl, 70 mg PEO, and 13.56% coating membrane weight gain. It revealed that this formulation could release PCN in vitro at a zero-order manner for 18 h. The in vivo release property of the PCN-PPOP tablet was assessed and contrasted with that of immediate-release (IR) tablet following a single oral administration to beagle dogs. The pharmacokinetic data indicated that the PPOP tablet achieved a sustained in vivo release of PCN, as evidenced by a longer Tmax (7.17 ± 1.83 h) and mean residence time (11.57 ± 1.12 h). This work demonstrated that PCN-PPOP tablet could be designed for oral administration to provide a long-term pharmacological intervention for motion sickness.

The presence of an avatar can reduce cybersickness in Virtual Reality

Virtual Reality (VR) applications are increasingly being utilized for research, healthcare, and education. Despite their benefits, many VR users report motion sickness-like sensations (cybersickness), such as headache, disorientation, or nausea. Previous studies suggest that the sense of presence ("being there") in the virtual world may contribute to the severity of cybersickness; however, results have been contradictory, with some studies reporting a negative and some reporting a positive relationship between the two. The goal of the current study was to further investigate how presence and cybersickness are related. Participants (N = 54) were exposed to a VR scene presented on a head-mounted display showing a 15-minute-long passive movement through space. The level of presence was manipulated by including an avatar (astronaut suit with hand-tracking) or no avatar in the virtual environment. Results showed that the avatar group reported significantly less severe cybersickness compared to the no-avatar group. We also found significant, negative correlations between some of the presence metrics (immersion, sensory fidelity) and cybersickness, indicating that cybersickness severity decreased as the level of presence increased. These findings suggest that more immersive VR experiences using an avatar may potentially reduce the risk of experiencing cybersickness.

Preregistered test of whether a virtual nose reduces cybersickness

Recent findings suggest that adding a visual depiction of a nose to virtual reality displays (virtual nose) can reduce motion sickness. If so, this would be a simple intervention that could improve the experience of a variety of VR applications. However, only one peer-reviewed study has reported a benefit from a virtual nose, and the effect was observed in a single low-powered experiment. To further test the effectiveness of a virtual nose for mitigating motion sickness in VR, we performed a preregistered experiment with higher power and better control. Subjects were presented with simulated movement in a virtual environment using a head-mounted display, and the resulting motion sickness was measured using the Fast Motion Sickness Scale (FMS) and the Simulator Sickness Questionnaire (SSQ). Conditions with and without a virtual nose were tested in separate sessions on different days, and the mean habituation effects were removed analytically. Awareness of the manipulation was assessed with a funnel debriefing procedure. The sample size (n = 32) was chosen to have over 90% power to detect the estimated effect size based on previous data (dz = 0.6). We found no significant difference between motion sickness in conditions with and without the virtual nose. The estimated effect size was close to zero, dz = - 0.02, with a 95% credible interval [- 0.37, 0.33]. Results from a Bayesian analysis imply that any benefit from a virtual nose is unlikely to be more than a 26% reduction in FMS scores, and any cost is unlikely to be more than a 23% increase. Our results do not support the hypothesis that a virtual nose is a general and effective way to relieve motion sickness in virtual reality.

Mixing transcutaneous vagal nerve stimulation and galvanic cutaneous stimulation to decrease simulator adaptation syndrome

Purpose

Simulator Adaptation Syndrome arises from a perceptual discordance between expected and actual motion, giving rise to symptoms such as nausea and disorientation. This research focused on determining the benefit of Transcutaneous Vagal Nerve Stimulation (tVNS) and Galvanic Cutaneous Stimulation (GCS), where both were applied in conjunction, as compared to their administration in isolation, to decrease Simulator Adaptation Syndrome (SAS).

Method

A driving simulation study was proposed where SAS, body balance, and driving performance were measured. These measurements were taken during seven different stimulation scenarios with a baseline condition without stimulation compared against tVNS and GCS conditions.

Results

The main result showed that the combination of tVNS and GCS reduced SAS and improved body balance and driving performance more successfully than their administration in isolation.

Conclusion

Similar neuromodulation in the temporoparietal junction is proposed to mitigate SAS for GCS and tVNS (although additional explanations are discussed). Applying both techniques simultaneously is encouraged to decrease SAS in future interventions.

Effects of within-day intervals on adaptation to visually induced motion sickness in a virtual-reality motorcycling simulator

This study investigated the effects of the time interval between virtual reality (VR) sessions on visually induced motion sickness (VIMS) reduction to better understand adaptation to and recovery from a nauseating VR experience. The participants experienced two 6-min VR sessions of a first-person motorcycle ride through a head-mounted display with (1) a 6-min interval, (2) an interval until the VIMS score reached zero, and (3) a 60-min interval. The results showed that for each condition, VIMS in the second session was aggravated, unchanged, or attenuated, respectively, indicating that additional resting time was necessary for VIMS adaptation. This study suggests that a certain type of multisensory learning attenuates VIMS symptoms within a relatively short time, requiring at least 20 min of additional resting time after subjective recovery from VIMS symptoms. This finding has important implications for reducing the time interval between repeated challenges when adapting to nauseating stimuli during VR experiences.

Alpha tACS on Parieto-Occipital Cortex Mitigates Motion Sickness Based on Multiple Physiological Observation

Approximately one third of the population is prone to motion sickness (MS), which is associated with the dysfunction in the integration of sensory inputs. Transcranial alternating current stimulation (tACS) has been widely used to modulate neurological functions by affecting neural oscillation. However, it has not been applied in the treatment of motion sickness. This study aims to investigate changes in brain oscillations during exposure to MS stimuli and to further explore the potential impact of tACS with the corresponding frequency and site on MS symptoms. A total of 19 subjects were recruited to be exposed to Coriolis stimuli to complete an inducing session. After that, they were randomly assigned to tACS stimulation group or sham stimulation group to complete a stimulation session. Electroencephalography (EEG), electrocardiogram, and galvanic skin response were recorded during the experiment. All the subjects suffering from obvious MS symptoms after inducing session were observed that alpha power of four channels of parieto-occipital lobe significantly decreased (P7: t =3.589, p <0.001; P8: t =2.667, p <0.05; O1: t =3.556, p <0.001; O2: t =2.667, p <0.05). Based on this, tACS group received the tACS stimulation at 10Hz from Oz to CPz. Compared to sham group, tACS stimulation significantly improved behavioral performance and entrained the alpha oscillation in individuals whose alpha power decrease during the inducing session. The findings show that parieto-occipital alpha oscillation plays a critical role in the integration of sensory inputs, and alpha tACS on parieto-occipital can become a potential method to mitigate MS symptoms.

Individual factors and vection in younger and older adults: How sex, field dependence, personality, and visual attention do (or do not) affect illusory self-motion

An important aspect to an immersive experience in Virtual Reality is vection, defined as the illusion of self-motion. Much of the literature to date has explored strategies to maximize vection through manipulations of the visual stimulus (e.g., increasing speed) or the experimental context (e.g., framing of the study instructions). However, the role of individual differences (e.g., age, biological sex) in vection susceptibility has received little attention. The objective of the current study was to investigate the influence of individual-difference factors on vection perception in younger and older adults. Forty-six younger adults (M age = 25.1) and 39 older adults (M age = 72.4) completed assessments of personality traits, field dependence, and visual attention prior to observing a moving visual stimulus aimed at inducing circular vection. Vection was measured using self-reports of onset latency, duration, and intensity. Results indicated that, in both age groups, females experienced longer-lasting vection compared to males. Additionally, the level of field dependence was related to vection intensity and duration in males but not in females. Variability in vection intensity was best explained by a mixture of biological, perceptual, cognitive, and personality variables. Taken together, these findings suggest that individual factors are important for understanding differences in vection susceptibility.

Scopolamine for patients with motion sickness: a systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Scopolamine has been demonstrated to relieve motion sickness. However, repeated significance testing may increase false-positive results.

OBJECTIVES

Review the efficacy and safety of scopolamine in the prevention of motion sickness by performing a meta-analysis with Trial Sequential Analysis (TSA).

MATERIAL AND METHODS

Randomized controlled trials (RCTs) compared scopolamine with other medications or placebo were included. Primary outcomes were nausea reported and head movement time.

RESULTS

Twenty studies with 753 participants were included. Scopolamine had a greater reported reduction in nausea than placebo (relative risk [RR] 0.35; 95% confidence interval [CI] 0.24 to 0.52; p<0.00001; I2 = 45%), while TSA showed the included sample size exceeded the required information size (RIS). There is no difference in head movement time between scopolamine and placebo (mean difference [MD] 2.02; 95% CI -1.2 to 5.25; p = 0.6; I2 = 0%), while the included sample size did not reach RIS.

CONCLUSION

Scopolamine is effective for motion sickness nausea compared to placebo. The TSA recommends conducting more head movement trials to validate the objective efficacy of scopolamine.

SIGNIFICANCE

Clarifying the efficacy of scopolamine for motion sickness, the TSA highlights the need for more prospective studies using head movement as an outcome.

Atrial Natriuretic Peptide Alleviates Motion Sickness Potentially through Regulating Endolymph Volume in the Inner Ear Increased by Arginine Vasopressin

INTRODUCTION

Dimenhydrinate and scopolamine are frequently used drugs, but they cause drowsiness and performance decrement. Therefore, it is crucial to find peripheral targets and develop new drugs without central side effects. This study aimed to investigate the anti-motion sickness action and inner ear-related mechanisms of atrial natriuretic peptide (ANP).

METHODS

Endolymph volume in the inner ear was measured with magnetic resonance imaging and expression of AQP2 and p-AQP2 was detected with Western blot analysis and immunofluorescence method.

RESULTS

Both rotational stimulus and intraperitoneal arginine vasopressin (AVP) injection induced conditioned taste aversion (CTA) to 0.15% sodium saccharin solution and an increase in the endolymph volume of the inner ear. However, intraperitoneal injection of ANP effectively alleviated the CTA behaviour and reduced the increase in the endolymph volume after rotational stimulus. Intratympanic injection of ANP also inhibited rotational stimulus-induced CTA behaviour, but anantin peptide, an inhibitor of ANP receptor A (NPR-A), blocked this inhibitory effect of ANP. Both rotational stimulus and intraperitoneal AVP injection increased the expression of AQP2 and p-AQP2 in the inner ear of rats, but these increases were blunted by ANP injection. In in vitro experiments, ANP addition decreased AVP-induced increases in the expression and phosphorylation of AQP2 in cultured endolymphatic sac epithelial cells.

CONCLUSION

Therefore, the present study suggests that ANP could alleviate motion sickness through regulating endolymph volume of the inner ear increased by AVP, and this action of ANP is potentially mediated by activating NPR-A and antagonising the increasing effect of AVP on AQP2 expression and phosphorylation.

Concussion can increase the risk of visually induced motion sickness

Concussion can lead to various symptoms such as balance problems, memory impairments, dizziness, and/or headaches. It has been previously suggested that during self-motion relevant tasks, individuals with concussion may rely heavily on visual information to compensate for potentially less reliable vestibular inputs and/or problems with multisensory integration. As such, concussed individuals may also be more sensitive to other visually-driven sensations such as visually induced motion sickness (VIMS). To investigate whether concussed individuals are at elevated risk of experiencing VIMS, we exposed participants with concussion (n = 16) and healthy controls (n = 15) to a virtual scene depicting visual self-motion down a grocery store aisle at different speeds. Participants with concussion were further separated into symptomatic and asymptomatic groups. VIMS was measured with the SSQ before and after stimulus exposure, and visual dependence, self-reported dizziness, and somatization were recorded at baseline. Results showed that concussed participants who were symptomatic demonstrated significantly higher SSQ scores after stimulus presentation compared to healthy controls and those who were asymptomatic. Visual dependence was positively correlated with the level of VIMS in healthy controls and participants with concussion. Our results suggest that the presence of concussion symptoms at time of testing significantly increased the risk and severity of VIMS. This finding is of relevance with regards to the use of visual display devices such as Virtual Reality applications in the assessment and rehabilitation of individuals with concussion.

Investigating Personalization Techniques for Improved Cybersickness Prediction in Virtual Reality Environments

In recent cybersickness research, there has been a growing interest in predicting cybersickness using real-time physiological data such as heart rate, galvanic skin response, eye tracking, postural sway, and electroencephalogram. However, the impact of individual factors such as age and gender, which are pivotal in determining cybersickness susceptibility, remains unknown in predictive models. Our research seeks to address this gap, underscoring the necessity for a more personalized approach to cybersickness prediction to ensure a better, more inclusive virtual reality experience. We hypothesize that a personalized cybersickness prediction model would outperform non-personalized models in predicting cybersickness. Evaluating this, we explored four personalization techniques: 1) data grouping, 2) transfer learning, 3) early shaping, and 4) sample weighing using an open-source cybersickness dataset. Our empirical results indicate that personalized models significantly improve prediction accuracy. For instance, with early shaping, the Deep Temporal Convolutional Neural Network (DeepTCN) model achieved a 69.7% reduction in RMSE compared to its non-personalized version. Our study provides evidence of personalization techniques' benefits in improving cybersickness prediction. These findings have implications for developing personalized cybersickness prediction models tailored to individual differences, which can be used to develop personalized cybersickness reduction techniques in the future.

Investigating cortical activity during cybersickness by fNIRS

This study investigated brain responses during cybersickness in healthy adults using functional near-infrared spectroscopy (fNIRS). Thirty participants wore a head-mounted display and observed a virtual roller coaster scene that induced cybersickness. Cortical activation during the virtual roller coaster task was measured using fNIRS. Cybersickness symptoms were evaluated using a Simulator Sickness Questionnaire (SSQ) administered after the virtual rollercoaster. Pearson correlations were performed for cybersickness symptoms and the beta coefficients of hemodynamic responses. The group analysis of oxyhemoglobin (HbO) and total hemoglobin (HbT) levels revealed deactivation in the bilateral angular gyrus during cybersickness. In the Pearson correlation analyses, the HbO and HbT beta coefficients in the bilateral angular gyrus had a significant positive correlation with the total SSQ and disorientation. These results indicated that the angular gyrus was associated with cybersickness. These findings suggest that the hemodynamic response in the angular gyrus could be a biomarker for evaluating cybersickness symptoms.

One simple question detects motion sickness susceptibility in migraine patients

OBJECTIVE

To find out if motion sickness susceptibility (MSS) of vestibular migraine (VM) patients and migraine only (MO) patients can be reliably detected with a single simple question: "Can you read while travelling in a car without getting motion sick?".

METHOD

Ninety-two definite VM and 58 MO patients and 74 healthy control (HC) subjects were asked about their MSS and about being able to read while riding in a car without becoming motion sick. A Motion Sickness Susceptibility Questionnaire (MSSQ-Short) including childhood (MSA), adulthood (MSB) and total (MST) parts was also administered to all participants. ROC curves of MSSQ-Short were prepared for "not being able to read in a car" as the gold standard.

RESULTS

Mean MSA scores were significantly higher in both VM and MO patients than in HCs (p < 0.001), but their scores were not significantly different (p = 0.171). Mean MSB and MST scores were significantly higher in VM than in MO patients (p < 0.001) and both VM and MO patients had significantly higher scores than HCs (p < 0.001). MSA scores were significantly higher than MSB scores in MO patients (p < 0.001). All sections of the questionnaire were associated with high area-under-curve values for MSS detected by the question about being able to read in a car without becoming motion sick.

CONCLUSION

We propose that all migraine patients could have the same level of MSS in childhood but MO patients are able to compensate over years, but VM patients are not. A quick way to determine MSS is to ask about the ability to read without becoming motion sickness while riding a car.

Measuring vection: a review and critical evaluation of different methods for quantifying illusory self-motion

The sensation of self-motion in the absence of physical motion, known as vection, has been scientifically investigated for over a century. As objective measures of, or physiological correlates to, vection have yet to emerge, researchers have typically employed a variety of subjective methods to quantify the phenomenon of vection. These measures can be broadly categorized into the occurrence of vection (e.g., binary choice yes/no), temporal characteristics of vection (e.g., onset time/latency, duration), the quality of the vection experience (e.g., intensity rating scales, magnitude estimation), or indirect (e.g., distance travelled) measures. The present review provides an overview and critical evaluation of the most utilized vection measures to date and assesses their respective merit. Furthermore, recommendations for the selection of the most appropriate vection measures will be provided to assist with the process of vection research and to help improve the comparability of research findings across different vection studies.

An old approach to a novel problem: effect of combined balance therapy on virtual reality induced motion sickness: a randomized, placebo controlled, double-blinded study

BACKGROUND

The objective of this study was to investigate the impact of a rehabilitation program aimed at addressing vestibular and proprioceptive deficits, which are believed to underlie the pathophysiology of motion sickness.

METHODS

A total of 121 medical students with motion sickness participated in this study and were randomly divided into intervention (n = 60) and placebo control (n = 61) groups. The intervention group underwent combined balance, proprioception, and vestibular training three times a week for 4 weeks, while the control group received placebo training. The study assessed various measurements, including the Virtual reality sickness questionnaire (VRSQ), tolerance duration, enjoyment level measured by VAS, stability levels using Biodex, and balance with the Flamingo balance test (FBT). All measurements were conducted both at baseline and 4 weeks later.

RESULTS

There was no significant difference in pre-test scores between the intervention and control groups, suggesting a similar baseline in both groups (p > 0.05). The results showed a significant improvement in VRSQ, tolerance duration, VAS, Biodex, and FBT scores in the intervention group (p < 0.05). While, the control group showed a significant increase only in VAS scores after 4 weeks of training (p < 0.05). A statistically significant improvement was found between the groups for VRSQ (p < 0.001), tolerance duration (p < 0.001), VAS (p < 0.001), Biodex (p = 0.015), and FBT scores (p < 0.05), in favor of the intervention group.

CONCLUSIONS

A combined balance training program for motion sickness proves to be effective in reducing motion sickness symptoms, enhancing user enjoyment, and extending the usage duration of virtual reality devices while improving balance and stability. In contrast, placebo training did not alter motion sickness levels. These findings offer valuable insights for expanding the usage of virtual reality, making it accessible to a broader population.

The effect of stretching exercises on the mobility of the spine in the sagittal plane in people using digital devices – preliminary observations

Introduction. Digital devices and a sedentary lifestyle pose significant health risks in today’s society, further exacerbated by the regular adoption of incorrect posture. Prolonged adoption of an incorrect posture can result in pain and impaired spinal mobility. Aim of the study. The study aims to evaluate the impact of stretching exercises on improving cervical, thoracic and lumbar spine mobility in the sagittal plane. Furthermore, it sought to examine the potential correlation between the occurrence of pain and the duration of digital equipment usage. Study materials and methodology. The study was conducted on a sample group of 22 individuals aged 18 to 21 (20.11 ± 1.56) years. Linear measurements, including the Schober and Otto-Wurm tests, were used to examine spinal mobility in the sagittal plane. The subjects were given a 10-day programme comprising six stretching exercises to perform autonomously daily. After ten days, line measurements were retaken. Results. Significant statistical values were observed for spinal ranges of motion in the sagittal plane; no statistically significant value was obtained for the incidence of pain and the duration of use of digital devices. Conclusions. The subjects demonstrated improvement in cervical, thoracic, and lumbar spine mobility in the sagittal plane following the implementation of stretching exercises. Additionally, a decrease in spinal pain was observed.

Evaluating proxies for motion sickness in rodent

Motions sickness (MS) occurs when the brain receives conflicting sensory signals from vestibular, visual and proprioceptive systems about a person's ongoing position and/or motion in relation to space. MS is typified by symptoms such as nausea and emesis and implicates complex physiological aspects of sensations and sensorimotor reflexes. Use of animal models has been integral to unraveling the physiological causality of MS. The commonly used rodents (rat and mouse), albeit lacking vomiting reflex, reliably display phenotypic behaviors of pica (eating of non-nutritive substance) and conditioned taste aversion (CTAver) or avoidance (CTAvoi) which utilize neural substrates with pathways that cause gastrointestinal malaise akin to nausea/emesis. As such, rodent pica and CTAver/CTAvoi have been widely used as proxies for nausea/emesis in studies dealing with neural mechanisms of nausea/emesis and MS, as well as for evaluating therapeutics. This review presents the rationale and experimental evidence that support the use of pica and CTAver/CTAvoi as indices for nausea and emesis. Key experimental steps and cautions required when using rodent MS models are also discussed. Finally, future directions are suggested for studying MS with rodent pica and CTAver/CTAvoi models.

Exploring neurophysiological correlates of visually induced motion sickness using electroencephalography (EEG)

Visually induced motion sickness (VIMS) is a common phenomenon when using visual devices such as smartphones and virtual reality applications, with symptoms including nausea, fatigue, and headache. To date, the neuro-cognitive processes underlying VIMS are not fully understood. Previous studies using electroencephalography (EEG) delivered mixed findings, with some reporting an increase in delta and theta power, and others reporting increases in alpha and beta frequencies. The goal of the study was to gain further insight into EEG correlates for VIMS. Participants viewed a VIMS-inducing visual stimulus, composed of moving black-and-white vertical bars presented on an array of three adjacent monitors. The EEG was recorded during visual stimulation and VIMS ratings were recorded after each trial using the Fast Motion Sickness Scale. Time-frequency analyses were conducted comparing neural activity of participants reporting minimal VIMS (n = 21) and mild-moderate VIMS (n = 12). Results suggested a potential increase in delta power in the centro-parietal regions (CP2) and a decrease in alpha power in the central regions (Cz) for participants experiencing mild-moderate VIMS compared to those with minimal VIMS. Event-related spectral perturbations (ERSPs) suggested that group differences in EEG activity developed with increasing duration of a trial. These results support the hypothesis that the EEG might be sensitive to differences in information processing in VIMS and minimal VIMS contexts, and indicate that it may be possible to identify neurophysiological correlate of VIMS. Differences in EEG activity related to VIMS may reflect differential processing of conflicting visual and vestibular sensory information.

Virtual reality to improve low-back pain and pelvic pain during pregnancy: a pilot RCT for a multicenter randomized controlled trial

A significant proportion of women experience low back and pelvic pain during and after pregnancy, which can negatively impact their daily lives. Various factors are attributed to these complaints, and many affected women do not receive adequate healthcare. However, there is evidence to support the use of different physiotherapeutic interventions to alleviate these conditions. Virtual reality is a promising complementary treatment to physiotherapy, particularly in improving pain perception and avoidance. The primary objective of this study is to evaluate the efficacy of a four-week program combining VR and physiotherapy compared to standard physiotherapy in pregnant women with low back and pelvic pain, in terms of improving pain avoidance, intensity, disability, and functional level. The study also aims to investigate patient satisfaction with the VR intervention. This research will be conducted through a multi-center randomized controlled clinical trial involving pregnant patients residing in the provinces of Seville and Malaga with a diagnosis of low back and pelvic pain during pregnancy. The alternative hypothesis is that the implementation of a Virtual Reality program in combination with standard physiotherapy will result in better clinical outcomes compared to the current standard intervention, which could lead to the development of new policies and interventions for these pathologies and their consequences. Clinical trial registration: clinicaltrials.gov, identifier NCT05571358.

Measuring the susceptibility to visually induced motion sickness and its relationship with vertigo, dizziness, migraine, syncope and personality traits

The widespread use of visual technologies such as Virtual Reality increases the risk of visually induced motion sickness (VIMS). Previously, the 6-item short version of the Visually Induced Motion Sickness Susceptibility Questionnaire (VIMSSQ short form) has been validated for predicting individual variation in VIMS. The aim of the current study was to investigate how the susceptibility to VIMS is correlated with other relevant factors in the general population. A total of 440 participants (201 M, 239F), mean age 33.6 (SD 14.8) years, completed an anonymous online survey of various questionnaires including the VIMSSQ, Motion Sickness Susceptibility Questionnaire (MSSQ), Vertigo in City questionnaire (VIC), Migraine (scale), Social & Work Impact of Dizziness (SWID), Syncope (faintness), and Personality ('Big Five' TIPI). The VIMSSQ correlated positively with the MSSQ (r = 0.50), VIC (r = 0.45), Migraine (r = 0.44), SWID (r = 0.28), and Syncope (r = 0.15). The most efficient Multiple Linear Regression model for the VIMSSQ included the predictors MSSQ, Migraine, VIC, and Age and explained 40% of the variance. Factor analysis of strongest correlates with VIMSSQ revealed a single factor loading with VIMSSQ, MSSQ, VIC, Migraine, SWID, and Syncope, suggesting a common latent variable of sensitivity. The set of predictors for the VIMSSQ in the general population has similarity with those often observed in patients with vestibular disorders. Based on these correlational results, we suggest the existence of continuum of underlying risk factors for sensitivity, from healthy population to patients with extreme visual vertigo and perhaps Persistent Postural-Perceptual Dizziness.

Brown Slime Cap Mushroom (Chroogomphus rutilus, Agaricomycetes) Polysaccharide Resists Motion Sickness by Inhibiting the Activity of the Serotonin System in Mice

Motion sickness (MS) is a disorder of the autonomic nervous system caused by abnormal exercise with symptoms such as nausea, vomiting and drowsiness. More than 90% of the human population has experienced different degrees of MS. At present, anticholinergics, antihistamines, and sympathomimetic drugs are used for treating MS, but these drugs generally have some adverse reactions and are not suitable for all people. Therefore, it is necessary to develop anti-MS drugs that have high efficiency and no adverse effects. Previous studies have found that Chroogomphus rutilus polysaccharide (CRP) is effective at preventing and treating MS in rats and mice. However, its mechanism of action is not clear. To clarify whether the CRP has anti-MS effects in mice, and to clarify its mechanism, we performed behavioral, biochemical, and morphological tests in a Kunming mouse model. Our results indicate that CRPs can significantly relieve the symptoms of MS, and their effect is equivalent to that of scopolamine, a commonly used anti-MS medicine. Our results indicate that CRPs may directly act on the gastrointestinal chromaffin cells to inhibit the synthesis and release of serotonin (5-hydroxytryptamine, or 5-HT) and thus reduce the signal from the gastrointestinal tract.

Transport of the patient with trauma: a narrative review

Trauma and injury place a significant burden on healthcare systems. In most high-income countries, well-developed acute pre-hospital and trauma care systems have been established. In Europe, mobile physician-staffed medical teams are available for the most severely injured patients and apply a wide variety of lifesaving interventions at the same time as ensuring patient comfort. In trauma systems providing pre-hospital care, medical interventions are performed earlier in the patient journey and do not affect time to definite care. The mode of transport from the accident scene depends on the organisation of the healthcare system and the level of hospital care to which the patient is transported. This varies from 'scoop and run' to a basic community care setting, to advanced helicopter emergency medical service transport to a level 4 trauma centre. Secondary transport of trauma patients to a higher level of care should be avoided and may lead to a delay in definitive care. Critically injured patients must be accompanied by at least two healthcare professionals, one of whom must be skilled in cardiopulmonary resuscitation and advanced airway management techniques. Ideally, the standard of care provided during transport, including the level of monitoring, should mirror hospital care. Pre-hospital care focuses on the critical care patient, but the majority of injured patients need only close observation and pain management during transport. Providing comfort and preventing additional injury is the responsibility of the whole transport team.

Can the Perceived Timing of Multisensory Events Predict Cybersickness?

Humans are constantly presented with rich sensory information that the central nervous system (CNS) must process to form a coherent perception of the self and its relation to its surroundings. While the CNS is efficient in processing multisensory information in natural environments, virtual reality (VR) poses challenges of temporal discrepancies that the CNS must solve. These temporal discrepancies between information from different sensory modalities leads to inconsistencies in perception of the virtual environment which often causes cybersickness. Here, we investigate whether individual differences in the perceived relative timing of sensory events, specifically parameters of temporal-order judgement (TOJ), can predict cybersickness. Study 1 examined audiovisual (AV) TOJs while Study 2 examined audio-active head movement (AAHM) TOJs. We deduced metrics of the temporal binding window (TBW) and point of subjective simultaneity (PSS) for a total of 50 participants. Cybersickness was quantified using the Simulator Sickness Questionnaire (SSQ). Study 1 results (correlations and multiple regression) show that the oculomotor SSQ shares a significant yet positive correlation with AV PSS and TBW. While there is a positive correlation between the total SSQ scores and the TBW and PSS, these correlations are not significant. Therefore, although these results are promising, we did not find the same effect for AAHM TBW and PSS. We conclude that AV TOJ may serve as a potential tool to predict cybersickness in VR. Such findings will generate a better understanding of cybersickness which can be used for development of VR to help mitigate discomfort and maximize adoption.

Study of clinical correlation of motion sickness in patients with vestibular migraine

Objective

In this study, clinical data from vestibular migraine (VM) patients and healthy control populations were collected to analyze the clinical data of VM patients, especially the history of motion sickness, and to understand their clinical characteristics.

Methods

According to VM diagnostic criteria, 140 patients diagnosed with confirmed VM (cVM) and probable VM (pVM) who attended the outpatient and inpatient ward of Jiaxing First Hospital between August 2017 and June 2021, as well as 287 healthy check-ups in the health management center, were analyzed and compared in terms of age, gender, and previous history of motion sickness.

Results

A comparison of clinical data related to VM patients and the control population showed that there were more women in the VM group (P < 0.01) and that patients in the VM group were older (P < 0.05) and had a higher prevalence of history of motion sickness history (P < 0.01). Analysis after matching gender and age revealed that patients in the cVM group were older than those in the pVM group (P < 0.05), but the proportion of motion sickness was lower than in the pVM group (P < 0.05). The age of the patients in the cVM group was mainly distributed around 50 years of age, following a normal distribution, whereas the age distribution of the patients in the pVM group did not have a significant trend of age concentration and was distributed at all ages.

Conclusion

The history of motion sickness is significant in patients with VM and may be a potential suggestive factor for the diagnosis of VM.

Normative data for rotational chair considering motion susceptibility

Objective

Rotational Chair Test (RCT) is considered one of the most critical measures for vestibular functionality, which generally includes the sinusoidal harmonic acceleration test (SHAT), velocity step test (VST), and visual suppression (VS). The purpose of this study was to establish normal values for different age groups on the RCT and investigate whether motion susceptibility, such as with a history of motion sickness or migraine, has any effects on test metrics.

Methods

One hundred and nine subjects aged from 20 to 59 years who were free from neurotological and vestibular disorders were enrolled. According to the history of motion sickness or migraine, participants were divided into four groups: the motion sickness (MS) group (n = 13), the migraine group (n = 8), comorbidity group (n = 11), and the control group (n = 77). The 77 subjects without any history of MS and migraine were then further separated into four age groups: youth group (20–29 years), young and middle-aged group (30–39 years), middle-age group (40–49 years), and middle-age and elderly group (50–59 years). All participants underwent SHAT, VST, and VS, and a comprehensive set of metrics including gain, phase, asymmetry, time constant (TC), and Fixation Index were recorded.

Results

Regarding the VST and VS, no significant differences were observed either across the four groups (MS, migraine, comorbidity, and control group) or four age categories within the control group. For SHAT, VOR gain at the frequency of 0.01 Hz, VOR phase from 0.08 to 0.64 Hz, and asymmetry at 0.01, 0.16, and 0.64 Hz indicated significant differences among various age groups (P < 0.05 for all comparisons). The VOR phase lead was lower in the migraine and comorbidity group than that in the control group at 0.64 Hz (P = 0.027, P = 0.003, respectively).

Conclusions

Age slightly affects the result of SHAT, but not for VST and VS. VOR gain is more susceptible to aging at low frequency, while the phase is opposite. Subjects with both migraine and motion sickness show abnormal velocity storage mechanisms. Phase bias should be considered when assessing motion susceptibility with the RCT. SHAT is more sensitive than VST in terms of reflecting motion susceptibility.