Showing papers on "Motion sickness published in 2004"

Visual field effects on motion sickness in cars.

Abstract: BACKGROUND: It is commonly assumed that car passengers who suffer from motion sickness will benefit from being able to see the road ahead. Hypothesis: It was hypothesized that variations in the external view (including restrictions to forward view and the provision of an artificial real-time video view) would affect the development of sickness during a 30-min suburban car journey. METHOD: Motion sickness was investigated in 4 experiments using 15 different conditions, with 20 subjects in each condition. The conditions involved artificial restrictions to view, restrictions arising from different seating positions, and the provision of a video view of the road ahead. Subjects provided ratings of motion sickness at 1-min intervals during the 30-min journey. The motion sickness susceptibility of subjects was matched between groups of subjects and the car motions were measured in three axes to determine whether the motion conditions were similar across conditions within each experiment. RESULTS: Absence of a visual field (blindfolded) resulted in similar sickness to that with no external forward view (with or without a side view). A wide or narrow forward view (with or without a side view) reduced sickness. For the conditions of these experiments, seating position did not significantly affect sickness. The provision of a real-time video view of the road ahead did not reduce motion sickness. There was circumstantial evidence that horizontal acceleration at frequencies below 0.1 Hz contributed to sickness. CONCLUSIONS: It is concluded that sickness in cars is dependent on the visual scene. The minimization of sickness by the provision of visual information requires improved understanding of those factors that combine to cause and suppress sickness. Language: en

Motion sickness: effect of the frequency of lateral oscillation.

Abstract: Introduction: low-frequency lateral oscillation is a cause of motion sickness in some forms of transport. However, the relationship between occurrence of sickness and the frequency of lateral oscillation is not known. This paper presents a study of motion sickness with lateral oscillation at frequencies between 0.0315 Hz and 0.20 Hz. Method: there were 120 subjects, in 6 groups of 20, who were exposed for up to 30 min to sinusoidal lateral oscillation with a peak velocity of 1.0 ms-1 at one of six frequencies (0.0315, 0.05, 0.08, 0.125, 0.16, 0.20 Hz). Subjects provided ratings of their motion sickness symptoms at 1-min intervals. Results: there was a highly significant effect of the frequency of lateral oscillation on the occurrence of mild nausea. Discussion: the present results have been combined with those from a previous experiment conducted with higher frequencies of oscillation to produce a frequency weighting for motion sickness caused by lateral oscillation over the range 0.0315 to 0.8 Hz. Conclusions: mild nausea caused by lateral oscillation may be predicted by an acceleration frequency weighting that is independent of frequency from 0.0315 to 0.25 Hz and reduces at 12 dB per octave (i.e., proportional to displacement) from 0.25 to 0.8 Hz. This weighting differs from the frequency weighting currently used for predicting motion sickness caused by vertical oscillation. The frequency weighting for lateral oscillation may not be applicable in those environments in which there is roll motion during lateral oscillation.

"Conflicting" motion cues to the visual and vestibular self-motion systems around 0.06 Hz evoke simulator sickness.

Abstract: The basic question this research addressed was, how does simulator sickness vary with simulated motion frequency? Participants were 11 women and 19 men, 20 to 63 years of age. A visual self-motion frequency response curve was determined using a Chattecx posture platform with a VR4 head-mounted display (HMD) or a back-projected dome. That curve and one for vestibular self-motion specify a frequency range in which vestibular and visual motion stimuli could produce conflicting self-motion cues. Using a rotating chair and the HMD, a third experiment supported (p < .01) the hypothesis that conflicting cues at the frequency of maximum “crossover” between the curves (about 0.06 Hz) would be more likely to evoke simulator sickness than would conflicting cues at a higher frequency. Actual or potential applications of this work include a preliminary design guidance curve that indicates the frequency range of simulated motion that is likely to evoke simulator or virtual reality sickness; for simulators intended to o...

Mal de debarquement and posture: reduced reliance on vestibular and visual cues.

Abstract: Objective The neural mismatch theory assumes that the intersensory conflicts leading to motion sickness are resolved by changes in the relative weighting of the various senses that contribute to orientation. If this sensory rearrangement persists after disembarkment, it might result in mal de debarquement (MD): ataxia and a rocking sensation sometimes felt after landing. The objective of the present study was to examine possible changes in sensory organization in naval crew members with differing susceptibility to MD with computerized dynamic posturography (CDP). Study Design Cross-sectional parallel-group design. Methods Seventeen subjects susceptible to MD (SMD) and 17 subjects nonsusceptible to MD (NSMD) (healthy male volunteers aged 18–22) participated in the study. CDP was performed twice with each subject, before and immediately after sailing, using the EquiTest system (NeuroCom, Inc., Clackamas, OR). Results The SMD group showed a significant reduction in their scores on sensory organization tests 3, 4, and 5 after sailing. Sensory pattern analysis revealed reduced use of inputs from the vestibular and visual systems to maintain balance. Prolonged latencies of the motor responses to unexpected pitch perturbations were also recorded in the postsailing CDP of the SMD group. Reduced performance on the presailing CDP task, which presents the greatest challenge to the vestibular system, was found to control for the presence of MD postsailing. Conclusions The results show that MD is associated with postural instability, slower motor reflexes, and larger sways in response to abrupt changes in the body's center of gravity. These findings may be explained by under reliance on vestibular and visual inputs and increased dependence on the somatosensory system for the maintenance of balance.

Side Effects of Virtual Environments: A Review of the Literature

Abstract: : Cybersickness symptoms are the unintended psychophysiological side effects of participation in virtual environments. Symptoms can occur both during and after participation, thus having implications for health and safety, user acceptance, and overall system effectiveness. Just as for other visually induced motion sickness, cybersickness is believed to result from sensory and perceptual mismatches between the visual and vestibular systems, and can be considered as a problem of adaptation to altered environments. Symptoms can be grouped into three dimensions: nausea, disorientation or postural instability, and visual symptoms. Numerous factors relating to the individual participants, the virtual reality system and virtual environment used, and the task carried out, can affect either incidence or severity of cybersickness. Taking account of these factors may avoid or minimize symptoms. This report reviews the literature on cybersickness, simulator sickness, and the relevant research on motion sickness, considers measures that have been proposed to manage and treat cybersickness, and identifies areas where more research is needed.

The role of vection, eye movements and postural instability in the etiology of motion sickness.

Abstract: Motion sickness is a term that is commonly used to describe the ill effects of many provocative motion (e.g. seagoing or air travel) and apparent motion (e.g. IMAX movies and virtual reality) environments on human well-being and performance. It can be extremely debilitating and yet we do not have a precise understanding of its cause. This study evaluates the importance of three factors that are purported to be involved in the etiology of motion sickness (MS). Most provocative motion environments cause three distinct, but possibly related, responses: reflexive eye movements (EM), sensory conflict (SC), and postural instability (PS). Three current theories, concerning the etiology of motion sickness, emphasize one of these responses, but deny the importance of the others. Such theoretical approaches preclude the possibility of a synergistic interaction of these factors. This experiment employed a three-factor experimental design wherein each factor was manipulated alone or in combination with the others. The independent variables involved two levels of: PS (induced by having the subject stand on a stationary platform or on a posturally challenging platform mounted atop a partially inflated rubber inner tube); SC (with or without illusory self movement elicited visually by whole field stimulation); and EM (unrestricted or controlled by a stable fixation point). Analysis of measures of PS, SC and EM confirmed the effectiveness of these manipulations. Analysis of MS measures (questionnaires, magnitude ratings, tolerance times) revealed a main effect of SC ( p< 0.01), increased MS found with illusory self motion conditions. In addition, measures of MS symptomatology revealed a significant three-way interaction between SC, PS and EM ( p< 0.05), greater amounts of MS found with conditions of illusory self motion, postural challenge, and unrestricted EM. This suggests support for a multi-factorial approach to the study of MS etiology. These findings suggest a major role of SC in the elicitation of MS, but also suggest important contributions from the EM and PS mechanisms.

Efficacy of acupressure and acustimulation bands for the prevention of motion sickness.

Abstract: Introduction The purpose of this study was to examine whether acupressure and acustimulation prevent motion sickness, taking into consideration whether or not the acupressure and acustimulation are administered properly. These techniques claim to reduce nausea through stimulation of the P6/Neiguan acupuncture point by applying acupressure or electrical acustimulation. Methods The Acuband and ReliefBand were used to administer acupressure and acustimulation, respectively. There were 77 subjects who were assigned to 1 of 5 conditions: Acuband trained or untrained; ReliefBand trained or untrained; or placebo. Subjects were exposed to a 20-min baseline and a maximum of 20 min of optokinetic drum rotation. Untrained subjects read the device directions, used it as they deemed appropriate, and completed a usability analysis following drum exposure. Trained subjects read the device directions and were trained to use the device appropriately prior to drum exposure. Symptoms and gastric myoelectric activity were monitored during baseline and rotation. Results In all conditions, symptoms of motion sickness and gastric tachyarrhythmia increased, and 3 cpm gastric myoelectric activity decreased, during drum exposure. The only difference found between conditions was a potential delay in symptom onset for the ReliefBand compared with the Acuband. While the Acuband was found difficult to use (0 untrained subjects used it correctly) and only a few minor usability issues were identified for the ReliefBand, usability had no impact on efficacy. Discussion Neither band nor placebo prevented the development of motion sickness, regardless of whether the bands were used correctly or incorrectly.

Vestibuloautonomic Interactions: A Teleologic Perspective

Abstract: A number of lines of evidence suggest that multiple sensory inputs that are influenced by gravitoinertial accelerations, including those from the vestibular labyrinth, retina, cutaneous and muscle receptors, baroreceptors, and abdominal visceral receptors, are integrated to produce an accurate perception of the location of the body in space, particularly during unusual conditions (e.g., swimming underwater). Such a processing of multiple sensory inputs appears to be important in coordinating appropriate motor and autonomic responses during movement and changes in posture. Although particular effector systems are most strongly influenced by particular sensory inputs (e.g., extraocular muscle contractions are driven powerfully be signals from semicircular canals, whereas components of the sympathetic nervous system that innervate vascular smooth muscle are strongly regulated by baroreceptor inputs), the “secondary inputs” and cerebellar contributions can potentially shape the responses, reduce their latency, and improve their accuracy. Because movement frequently requires coordinated changes in limb, axial, and respiratory muscle activity, accompanied by stereotyped adjustments in the cardiovascular system, it is important to explore the organization of components of “central motor programs” or “central pattern generators” that coordinate both motor and autonomic responses during the execution of movement. In addition to motor control, it is important to acknowledge the implications of the extensive convergence of vestibular and autonomic afferent information in the brain stem and cerebellum for spatial perception and affective changes associated with motion sickness and vestibular dysfunction. It appears that responses of vestibular and nonvestibular receptors to gravitoinertial challenges are integrated centrally to generate perceptual representations of gravitoinertial challenges. In addition, the visceral manifestations of motion sickness and vestibular dysfunction may be regarded as referred visceral discomfort related to gravitoinertial stimulation in the same sense that angina pectoris is a referred somatic pain related to cardiac dysfunction (Balaban 1999). Because these referred complaints are unpleasant and are not readily attributed to balance function, they may serve as eliciting or reinforcing stimuli for conditioned avoidance of situations that evoke discomfort. This conditioned avoidance may be one aspect of the linkage between balance disorders, height vertigo, and agoraphobia (Balaban 1999).

Effects of Duration of Immersion in a Virtual Reality Environment on Postural Stability

Abstract: Few studies have been carried out to examine the relation between postural stability and subjective reports or feelings of motion sickness. Two views seem to exist on the relation between immersion in a virtual reality (VR) environment and subjective feelings of motion sickness. One predicts that the immersion induces both postural instability and motion sickness. Another view is that preimmersion postural instability predisposes people to motion sickness. However, these views are not supported by empirical research. Longer immersions in a VR environment may induce higher levels of postural instability and symptoms of motion sickness. In this study, effects of long-hours immersion in a VR environment on postural stability were examined to approach the underlying mechanism of postural instability and motion sickness using force platform measurement and self-reported questionnaire on motion sickness. As a result, it was suggested that longer immersion in a VR environment induced postural instability and sym...

Suppression of Pain and the R2 Component of the Blink Reflex During Optokinetic Stimulation

Abstract: The effect of exposure to a rotating optokinetic drum on the electrically evoked blink reflex was investigated in 20 healthy volunteers. Pain ratings and the area under the curve of the R2 component of the blink reflex to innocuous and nociceptive trigeminal stimulation decreased substantially during and after optokinetic stimulation. At low shock intensities, R2 decreased most during optokinetic stimulation in subjects who did not develop symptoms of motion sickness. In contrast, during the recovery period after optokinetic stimulation, suppression of R2 to moderate and intense stimuli was greatest in the most nauseated subjects. These findings suggest that a mechanism that suppresses symptoms of motion sickness during sensory conflict also inhibits activity in wide dynamic range neurones in the trigeminal nucleus caudalis. Nausea in the absence of sensory conflict may inhibit R2 to intense electrical stimulation by provoking diffuse noxious inhibitory controls.

Motion sickness induced by optokinetic drums.

Abstract: Motion sickness is not only elicited by certain kinds of self-motion, but also by motion of a visual scene In case of the latter, optokinetic drums are often used and a visual-vestibular conflict is assumed to cause the sickness When the rotation axis is Earth vertical however, different studies show different results Here, we propose that visual-vestibular conflicts per se do not cause sickness whereas subjective vertical mismatch theory can reconcile the disparate findings The theory attributes the nausea induced by horizontal optokinetic stimulation to the subjects self-inducing pseudo-Coriolis by head movement This highlights the shortcomings of an optokinetic apparatus-that is non-rigid or inaccurately oriented-and the importance of constraining the subject's behavior

Effects of virtual body motion on visually-induced motion sickness

Abstract: To reduce possibilities of visually-induced motion sickness caused by animations, video games and movies, we need to develop an evaluation method of visually-induced motion sickness. Our previous results have shown that virtual roll motion had the most effective for producing the sickness. In the present study, we focused on the effectivity of image types, such as random dots and ordinary scene, and also the effectivity of virtual rotation speed on the sickness. In the first experiment, we confirmed our former results that virtual roll motion produced the highest score relating motion sickness, regardless of image types. In the second experiment, virtual rotation speed of 30 to 60 deg/s gave the highest scores regardless of the rotation types, yawing, pitching and rolling. We concluded that moving images simulating nonreciprocating rolling has robust effects on the sickness. Moreover, we speculated that the effect of rotation speed is determined by inconsistency of visual and nonvisual information, but not by retinal image speed.

Protein-predominant meals inhibit the development of gastric tachyarrhythmia, nausea and the symptoms of motion sickness.

Abstract: Summary Background : Meal ingestion has been suggested to reduce susceptibility to the development of gastric tachyarrhythmia, the abnormal activity of the stomach that frequently accompanies nausea. Aim : To determine the types of meal that are most effective in preventing the development of gastric tachyarrhythmia, nausea and the symptoms of motion sickness provoked by a rotating optokinetic drum. Method : Participants received a carbohydrate beverage, a protein-predominant beverage or nothing immediately before exposure to the rotating drum. Subjective symptoms of motion sickness and electrogastrograms were collected during a 6-min baseline period and a subsequent 16-min drum rotation period. Results : Subjective symptoms of motion sickness scores were significantly more severe during the no-meal condition than during either the protein or carbohydrate condition. Central, peripheral and, to some extent, gastrointestinal symptoms were more severe during the carbohydrate condition than during the protein condition. Gastric tachyarrhythmia increased significantly less from baseline to drum rotation during both the protein and carbohydrate conditions than during the no-meal condition. Conclusions : Liquid protein-predominant meals were most effective in suppressing both the development of gastric tachyarrhythmia and the entire spectrum of motion sickness symptoms, including nausea.

Scopolamine for preventing and treating motion sickness.

Abstract: BACKGROUND: Motion sickness - the discomfort experienced when perceived motion disturbs the organs of balance - may include symptoms such as nausea, vomiting, pallor, cold sweats, hypersalivation, hyperventilation and headaches. The control and prevention of these symptoms have included pharmacological, behavioural and complementary therapies. Although scopolamine has been used in the treatment and prevention of motion sickness for decades, there have been no systematic reviews of its effectiveness. OBJECTIVES: To assess the effectiveness of scopolamine versus no therapy, placebo, other drugs, behavioural and complementary therapy or two or more of the above therapies in combination for motion sickness in persons (both adults and children) without known vestibular, visual or central nervous system pathology. SEARCH STRATEGY: The Cochrane Ear, Nose and Throat Disorders Group Specialised Register, the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 4, 2003), MEDLINE (OVID, 1966 to March Week 1 2004), EMBASE (1974 to 2004) CINAHL (Ovid, 1982 to March Week 1 2004) and reference lists of retrieved studies were searched for relevant studies. No language restrictions were applied. SELECTION CRITERIA: All parallel-arm, randomised controlled trials (RCTs) focusing on scopolamine versus no therapy, placebo, other drugs, behavioural and complementary therapy or two or more of the above therapies in combination were included. Outcomes relating to the prevention of onset or treatment of clinically-defined motion sickness, task ability and psychological tests, changes in physiological parameters and adverse effects were considered. DATA COLLECTION AND ANALYSIS: Data from the studies were extracted independently by two authors using standardised forms. Study quality was assessed. Dichotomous data were expressed as odds ratio (OR) and a pooled OR was calculated using the random effects model. MAIN RESULTS: Of 27 studies considered potentially relevant, 12 studies enrolling 901 subjects met the entry criteria. Scopolamine was administered via transdermal patches, tablets or capsules, oral solutions or intravenously. Scopolamine was compared against placebo, calcium channel antagonists, antihistamine, meth-scopolamine or a combination of scopolamine and ephedrine. Studies were generally small in size and of varying quality.Scopolamine was more effective than placebo in the prevention of symptoms. Comparisons between scopolamine and other agents were few and suggested that scopolamine was superior (versus meth-scopolamine) or equivalent (versus antihistamines) as a preventative agent. Evidence comparing scopolamine to cinnarizine or combinations of scopolamine and ephedrine is equivocal or minimal.Although sample sizes were small, scopolamine was no more likely to induce drowsiness, blurring of vision or dizziness compared to other agents. Dry mouth was more likely with scopolamine than with meth-scopolamine or cinnarizine.No studies were available relating to the therapeutic effectiveness of scopolamine in the management of established symptoms of motion sickness. REVIEWERS' CONCLUSIONS: The use of scopolamine versus placebo in preventing motion sickness has been shown to be effective. No conclusions can be made on the comparative effectiveness of scopolamine and other agents such as antihistamines and calcium channel antagonists. In addition, no randomised controlled trials were identified that examined the effectiveness of scopolamine in the treatment of established symptoms of motion sickness.

Absence of short-term vestibular modulation of muscle sympathetic outflow, assessed by brief galvanic vestibular stimulation in awake human subjects

Abstract: There is evidence in experimental animals for a potent vestibulosympathetic reflex, but its existence in humans is controversial. Static head-down neck flexion and off-vertical axis rotation have been shown to increase muscle sympathetic nerve activity (MSNA), but not skin sympathetic nerve activity (SSNA), whereas horizontal linear acceleration decreases MSNA in humans. However, both forms of stimuli also activate other receptors. To examine the effects of a pure vestibular stimulus on MSNA and SSNA, and its potential interaction with the baroreceptors, we used galvanic vestibular stimulation (GVS) in 12 healthy seated subjects. MSNA was recorded in ten subjects via a percutaneous microelectrode in the peroneal nerve; ECG, blood pressure, respiration, skin blood flow and sweating were also recorded. GVS (2 mA, 1 s pulse) was delivered via surface electrodes over the mastoid processes at unexpected times, triggered from the R-wave with a delay of 0, 200, 400 or 600 ms. In addition to causing robust postural illusions, GVS caused cutaneous vasoconstriction and sweat release in all subjects (due to a short-latency increase in SSNA, three subjects), but no significant change in MSNA. The failure of GVS to elicit a change in muscle sympathetic nerve activity, as documented by averaging, suggests that the vestibular system is not engaged in short-term modulation of muscle sympathetic activity. Conversely, phasic vestibular inputs do excite cutaneous sympathetic neurones, consistent with the observation that motion sickness is accompanied by pallor and sweating.

Objective measurement of simulator sickness and the role of visual-vestibular conflict situations: a study with vestibular-loss (a-reflexive) subjects

Abstract: Simulators, in particular driving simulators, are gaining importance not only for research and development purposes, but also for education, training and even recreation. Progress in computer graphics and performance allow for highly realistic simulator visuals. High-end models are becoming somewhat better at generating acceptable inertial self-motion information, sometimes even providing real (but limited) linear translation in addition to angular movements. Simpler versions do not generate inertial information at all (fixed-base simulators). Here, we present a study on a problem that often occurs with driving simulators, i.e., simulator sickness. This phenomenon closely resembles the classically experienced motion sickness and can make a user abort a simulator run within minutes. We investigated the hypothesis that simulator sickness is caused by a visual-vestibular conflict, comparing susceptibility in normals and in vestibular-loss patients. We studied the psychophysical reactions of subjects, and quantitatively recorded their neurovegetative activity, to improve understanding of the underlying causes of simulator sickness, and to develop an objective measure for monitoring purposes. We used a fixed-base simulator, with an urban circuit with many sharp turns and traffic lights. No vestibular input was received during driving simulation, thus creating numerous visual-vestibular conflict situations. Subjects were asked to indicate continuously their discomfort on a visual-analog scale. We studied 33 normals (19 became sick) and 6 bilateral vestibular-loss subjects (one became truly sick, 2 others somewhat). Sickness correlated strongly with an increase in anxiety (Spielberger STAI). The subjective discomfort readings correlated well with simultaneous neurovegetative data and with a symptom scoring test administered immediately afterwards. There was no clear indication of an age or gender dependence in the normals. The fact that a complete vestibular-loss patient became sick indicates that more parameters may be responsible for simulator sickness than just a visuo-vestibular conflict situation (anxiety, nauseating odours, etc.). - Supported by the European Union (QLK6-CT-2002-00151: EUROKINESIS).

Sopite symptoms in the optokinetic drum.

Abstract: Aviat space Environ Med zuu4; 75:872-5. Introduction: Sopite syndrome is a disturbance caused by motion characterized by drowsiness and mood changes that may occur without the classic symptoms of motion sickness. Because sopite symptoms are often subtle, it is important to assess for their presence, and to distinguish true sopite symptoms from changes in mood and drowsiness that are due to non-motion related factors such as fatigue and boredom. We compared sopite symptoms in the optokinetic drum (OKD) with symptoms in a control condition in which the drum's motion cues were removed. Methods: There were 48 Introductory Psychology students who were randomly assigned to 1 of 2 groups: the rotating stripes group (RS) sat inside a drum lined with black and white stripes. The drum rotated at 5 rpm. The control group (Ctrl) sat inside the same drum without stripes or rotation. All participants completed the Positive and Negative Affect Scale (PANAS), the Motion Sickness Assessment Questionnaire (MSAQ), and the Epworth Sleepiness Scale (ESS) at pre- and post-drum exposures. Results: The RS, but not the Ctrl, showed increases on all four MSAQ subscales (gastric, peripheral, central, sopite). The groups showed equivalent decreases in positive and negative affect. These findings show that some sopite-related symptoms were due specifically to the motion stimuli, while others could be attributed to non-motion aspects of the experimental situation. Discussion: The findings have implications for the use of control conditions in the study of sopite syndrome, and for methods of assessing the changes in mood and drowsiness that are the cardinal symptoms of sopite.

Chlorpheniramine for motion sickness.

Abstract: Background Motion sickness remains a significant problem for travelers and for those involved in naval, aviation and space operations. Many motion sickness remedies are also sedating, making them undesirable in many settings. Methods We studied chlorpheniramine as a potential motion sickness treatment. A placebo-controlled, double-blind, dose-ranging trial was performed to establish the most effective dose and the drug's effects on cognition. Eighteen normal, motion sickness susceptible subjects received placebo, low dose (4 mg) or high dose (12 mg) chlorpheniramine 3.5 hours before off-axis vertical rotation. Cognitive testing included a battery of objective and subjective tests performed before drug ingestion, at peak drug effect and following rotation. Results Chlorpheniramine significantly increased the time in the chair compared to placebo at high dose (7.2 minutes to 11.7 minutes) and low dose (7.2 minutes to 10.2 minutes). Chlorpheniramine did not affect performance on objective cognitive tests. Subjects reported significantly more sleepiness and less alertness with high-dose chlorpheniramine, although they could not reliably determine when they had received active drug. Conclusion Chlorpheniramine is effective and could be considered for use against motion sickness. Chlorpheniramine also has the potential to be administered transdermally.

Protein-predominant meals inhibit the development of gastric tachyarrhythmia, nausea and the symptoms of motion sickness

Abstract: SUMMARY Background: Meal ingestion has been suggested to reduce susceptibility to the development of gastric tachyarrhythmia, the abnormal activity of the stomach that frequently accompanies nausea. Aim: To determine the types of meal that are most effective in preventing the development of gastric tachyarrhythmia, nausea and the symptoms of motion sickness provoked by a rotating optokinetic drum. Method: Participants received a carbohydrate beverage, a protein-predominant beverage or nothing immediately before exposure to the rotating drum. Subjective symptoms of motion sickness and electrogastrograms were collected during a 6-min baseline period and a subsequent 16-min drum rotation period. Results: Subjective symptoms of motion sickness scores were significantly more severe during the nomeal condition than during either the protein or carbohydrate condition. Central, peripheral and, to some extent, gastrointestinal symptoms were more severe during the carbohydrate condition than during the protein condition. Gastric tachyarrhythmia increased significantly less from baseline to drum rotation during both the protein and carbohydrate conditions than during the no-meal condition. Conclusions: Liquid protein-predominant meals were most effective in suppressing both the development of gastric tachyarrhythmia and the entire spectrum of motion sickness symptoms, including nausea.

Motion sickness countermeasure device and motion sickness countermeasure method

Abstract: PROBLEM TO BE SOLVED: To provide a motion sickness countermeasure device and a motion sickness motion sickness countermeasure method which can detect the motion sickness based on a behavior and physiological change to reduce the degree of the motion sickness. SOLUTION: The device is provided with: a passenger state detection part 10 for detecting the state of a passenger in a vehicle and generating passenger state information; a vehicle state detection part 20 for detecting information on the state of the vehicle and generating vehicle state information; a data processing and storing part 40 for storing the passenger state information, the vehicle state information and information on a motion sickness discrimination threshold used for discriminating whether the passenger is in the state of the motion sickness; a motion sickness discrimination part 30 for discriminating whether the passenger is in the state of the motion sickness based on the information stored in the data processing and storing part 40 and deciding whether to take a measure for curing when discriminating that the passenger is in the state of the motion sickness; and a curing part 50 for taking the measure for curing for reducing the degree of the motion sickness when the motion sickness discrimination part discriminates to take the measure for curing. COPYRIGHT: (C)2006,JPO&NCIPI

A linear physiological visual-vestibular interaction model for the prediction of motion sickness incidence

Abstract: : (MAXIMUM 200 WORDS) This thesis proposes a linear model based on human physiology for the explanation of the Motion Sickness Incidence (MSI) data found in previously reported experiments. The major human sensory systems taken into account are vestibular, visual, and the interaction between these two. The model is validated against the previous descriptive model and the corresponding experimental data. The proposed model predicts MSI with adequate precision (less than 5%) in the frequency range between 0.07 Hz and 0.25 Hz. The difference between the proposed model and the previous descriptive model is increased at the outer frequency regions of the data.

Evaluation of the effect of visually-induced motion sickness based on pulse transmission time and heart rate

Abstract: To evaluate the effects of visual stimulation on humans by using the physiological index which can be obtained from a compact and low-cost device, the maximum cross-correlation coefficient from pulse wave transmission time (PTT) to heart rate was introduced. This index was compared with the similar index based on blood pressure in place of PTT in the experiment in which 51 subjects were watching video image to induce motion sickness.

Motion sickness: its pathophysiology and treatment.

Abstract: The pathogenesis of motion sickness includes both inner-ear stimulation by body movement, especially a Coriolis-type stimulus, and optokinetic stimulation due to the shift of the surrounding visual fields. According to Kornhuber, Sakata and others, the vestibular cerebellum also participates in an important way. We conducted this study to elucidate the influence of the vestibular cerebellum on the development of motion sickness. We initially focused attention on the visual suppression test of Takemori et al. as a test for vestibular cerebellar function. We reported a modification of this test, described as postrotatoric nystagmus. We employed this test as a rotatoric visual suppression test using milder stimulus for patients complaining of motion sickness. The pathogenesis and treatment of motion sickness are also discussed.

Influence of attention and predictive visual cue on motion perception and sickness in immersive virtual environment

Abstract: Relieving motion sickness and enhancing self-motion perception are required for the public application of immersive visual display system. The effects of user attention and predictive visual cue have been experimentally evaluated in this study. A viewpoint moving visual stimulus was applied to eighteen healthy adults. The subjective evaluation presumably suggested that a predictive visual cue enhances self-motion perception and relieves motion sickness at a same time.