Motion Sickness Manifestations and Prevention

Motion sickness is an ancient problem associated with transportation (ships and other vehicles), which is affecting humans since ages. Motion sickness is characteristically occurring during abnormal movements induced by the motion and when there is a conflict between various senses such as visual, vestibular and motor system. Depending on the type of motion, various kinds of sicknesses, such as air sickness, car sickness, train sickness, seasickness, etc. may occur. A very less per cent of individuals are highly susceptible to motion sickness and very less per cent of individuals are highly insusceptible for motion sickness. However, most of the population comes in between. The primary symptoms of motion sickness include nausea, vomiting, wanes, and cold sweating. Varieties of drugs are available to reduce susceptibility to motion sickness. However, nausea, pallor, sweating, headache, dizziness, malaise, increased salivation, apathy, drowsiness, belching, hyperventilation and stomach awareness are the other symptoms of motion sickness. Anti-cholinergics and anti-histamines are the most effective motion sickness prophylactics with apparent side effects such as dry mouth, drowsiness, and depression. There are theories and mechanisms which include intra-vestibular (Canal-Otolith) mismatch theory, sensory conflict theory, visual-vestibular mismatch theory, the poison theory, the postural instability theory, and the movement program theory. Benzodiazepines, anticholinergics, anti-histamines and monoamine antagonists have commonly used treatment regimes. The traditional way of tackling the problem is the consumption of ginger, peppermint, lemon, fennel, marjoram, rosemary, basil. This review summarizes prediction and evaluation, behavioural strategies to prevent or minimize symptoms of motion sickness and available countermeasures of motion sickness

Vestibular symptoms and relations with postural balance, inner ear function, and long term survival

Bakgrunn: Svimmelhet og balanseproblemer er vanlige symptomer som i befolkningsstudier har vært assosiert med økt dødelighet, men det er ikke kjent om det er sykdommer i balanseapparatet som forårsaker denne økte dødeligheten. Kunnskapsgrunnlaget for å vurdere og behandle pasienter med svimmelhet har vært vurdert som dårlig og ofte er det kun pasientens beskrivelse av symptomer som danner grunnlaget for å diagnostikken. Mål: Å evaluere hvilke symptomer som gir nyttig informasjon, og undersøke sammenhenger mellom balanse, funksjonen av det indre øre og langtidsoverlevelse. Materialer og metode: En gruppe pasienter henvist for vurdering med tanke på vestibulær sykdom i perioden mellom 1992 og 2004. Resultater: De fleste pasienter (72,1%) valgte kun en tids-kategori for å beskrive sine symptomer, mens mindre enn halvparten (47,1%) valgte kun en type svimmelhet. Oppkast var assosiert med økt risiko for asymmetri på kalorisk prøve (odds ratio 1,50. 95% konfidensintervall 1,24-2,06). 10-dB økning i hørselstap på det best hørende øret var assosiert med 6,0% økning i kurvelengde. Standardisert mortalitetsrate var 1,03 (0,94-1,12). Periodiske eller korte anfall av svimmelhet var assosiert med redusert dødelighet med hasard rate på henholdsvis 0,62 (0,50-0,77) og 0,76 (0,63-0,93). Pasient-rapportert ustøhet og ustøhet målt ved posturografi var assosiert med økt dødelighet med hasard rate på 1,30 (1,08-1,47) og 1,44 (1,14 – 1,82). Konklusjon: Det bør fokuseres på tidsaspektet av vestibulære symptomer og det bør skilles mellom oppkast og kvalme. Hvilken type svimmelhet pasienten opplever gir noe tilleggsinformasjon, men virker ikke å være nyttig for å kunne gruppere pasienter. Vestibulær sykdom kunne ikke forklare sammenhengen mellom hørsel og balanse i denne studien og vestibulær sykdom ser ikke ut til å være hovedårsaken til den økte dødeligheten blant personer med svimmelhet og balanseplager i den generelle befolkningen. For å finne årsakssammenhenger er det behov for ytterligere studier på dødsårsaker blant pasienter med vestibulære symptomer, vestibulær sykdom, dårlig balanse og nedsatt hørsel.Background: Dizziness and unsteadiness are common symptoms that can be caused by pathologies in various organ-systems. In the general population such symptoms are associated with increased mortality, but it is not known if this increased mortality is caused by vestibular pathology. Today, many of the common vestibular diagnoses depend on patient-reported symptoms alone, and the evidence base for evaluating and treating patients with dizziness has been described as low. Aim: To critically evaluate which symptoms reported by dizzy patients provide useful information, and further to evaluate the interrelations between posturography, inner ear function, and long-term survival. Material and methods: A cohort of patients examined from 1992 to 2004 at an otolaryngology department for suspected vestibular disorder. Results: While most patients (72.1%) chose only one timing category, fewer than half the patients (47.1%) describe their complaints with only one type of dizziness. Vomiting was associated with increased risk for caloric asymmetry (Odds ratio 1.60, 95 % CI 1.24–2.06). A 10-dB increase in hearing loss in the best-hearing ear was associated with a 6.0% increase in path length measured on a balance platform. The standardized mortality ratio was 1.03 (0.94–1.12). Periodic or short attacks of dizziness were associated with reduced mortality with a hazard ratio of 0.62 (0.50–0.77) and 0.76 (0.63–0.93), respectively. Both self-reported and unsteadiness on posturography were associated with increased mortality with a hazard ratio of 1.30 (1.08–1.47) and 1.44 (1.14–1.82). Conclusions: The timing of vestibular symptoms and a differentiation between nausea and vomiting should be targeted when interviewing patients. The type of dizziness provides additional information but does not appear useful for categorization. The association between hearing and postural balance was not explained by unilateral vestibular disorders. Vestibular pathology is probably not the main cause of the increased mortality seen among patients with vestibular symptoms and balance problems in the general population. Further studies exploring cause of death related to vestibular symptoms, hearing, and postural balance are advocated.Doktorgradsavhandlin

The effects of aging and unilateral vestibular disorders on the kinematic performance of vestibular rehabilitation exercises and physical function

The overall purpose of this study was to evaluate the effects of unilateral vestibular disorders and aging on functional performances of activities of daily living and vestibular rehabilitation exercises by examining the correlations among actual and perceived functional measures, the kinematic measurement differences among young healthy adults, older healthy adults, and older adults with unilateral vestibular deficits, and the correlations between kinematic and functional measures. Perceived and actual functional abilities and kinematic variables were compared for young controls, older healthy controls, and patients with unilateral vestibular hypofunction with no previous vestibular rehabilitation. In older adults, better strength, balance, coordination, and endurance during activities of daily living were associated with better perceived ambulation and reduction in perceived functional handicap. Older adults had difficulties stabilizing their heads relative to the environment during eye exercises and moved their heads more when the exercise required head stabilization relative to the body, probably due to alterations in performance of the exercises. Patients, who were also older adults, were able to suppress some of these movements, likely to prevent dizziness. Both older groups often reduced their head movements and/or moved differently from the young when movements were self-selected and not externally driven by a visual cue. When patients were forced to make greater horizontal head movements with intermittent gaze stabilization, they also made greater head movements orthogonal to the plane of motion for seated exercises. These findings show that some patient differences are linked to declines of normal aging and not that of the disorder. In addition patients took more steps at a slower pace for the gait with head movement exercise. The group differences in exercise kinematics guided the correlations between kinematics and functional data, so that the subject differences in correlations between actual function and head excursion kinematics differed from those for perceived function and head excursion kinematics. These data add to the limited findings on associations between kinematic measurements and functional performances in vestibular patients and are the first to show relationships exist between these measures for healthy young adults, healthy older adults and vestibular patients

Dizziness

"The feelings of dizziness and vibrations are closely related. Most people experience vibrations at one point or another, and some even frequently. The unmistakable feeling of the body vibrating can be overwhelming. More often, though, the feeling is less distinct, and the vibrations are ignored or brushed aside as being caused by something else, like a truck passing, the floor rocking, a sudden spell of wobbliness. In dance and ritual, vibrations are made visible through the shaking of the performers. This shaking, as well as the vibrations that are sensed but unseen, can be understood as the first step in a transformation: a signal from phantom bodies, lost memories, and new identities trying to wriggle their way out. Joachim Koester (artist) This book gets your head spinning. While being bombarded by daily reports of crises (both real and fictional), while destabilization has become normal and feelings of disorientation, fear, and dizziness have started to prevail in our everyday lives, the contributors to this book reverse this perspective by emphasizing that dizziness is a valuable resource. Dizziness—A Resource is the result of the cross-disciplinary research project initiated in 2014 by artistic duo Ruth Anderwald and Leonhard Grond. What can we gain when balance is lost? How can anarchy and dizziness empower us? How can a cognitive vertigo fuel our cognition? Artists, scientists, philosophers, and art critics attempt to answer these questions and to show us how to navigate a world marked by unpredictable change. Małgorzata Ludwisiak (director, Ujazdowski Castle Centre for Contemporary Art, Warsaw) With contributions by Ruth Anderwald, Mathias Benedek, Oliver A. I. Botar, Katrin Bucher Trantow, Davide Deriu, Karoline Feyertag, Leonhard Grond, Sarah Kolb, François Jullien, Rebekka Ladewig, Jarosław Lubiak, Alice Pechriggl, Oliver Ressler, Maya M. Shmailov, Maria Spindler, Marcus Steinweg

The impact of vestibular modulations on whole brain structure and function in humans

The vestibular system is a sensory system that monitors active and passive headmovements while at the same time permanently sensing gravity. Vestibular information is important for maintaining balance and stabilisation of vision and ultimately for general orientation in space. A distributed set of cortical vestibular regions process vestibular sensory information, together with other sensory and motor signals. How these brain regions are influenced by or interact with each other, and how this depends on the context in which the system is acting is not well understood. In my research I investigated the whole brain consequences of different vestibular sensory contexts by means of structural and functional magnetic resonance (MR) imaging on three different time scales (long-term, short-term, and medium-term). For the long-term time scale, I investigated functional brain connectivity in individuals experiencing a type of chronic dizziness that cannot be explained by structural damage within the nervous system. These patients exhibit chronic or long-term alterations in their processing of vestibular information, which leads to dizziness and vertigo. I found altered sensory and cerebellar network connectivity when they experience a dizziness-provoking stimulus. These two networks contain, but are not limited to, vestibular processing regions, demonstrating the importance of a whole-brain approach. The alterations correspond the notion that these patients have dysfunctional stimulus expectations. The short-term vestibular processing I investigated was the effect of artificial vestibular stimulation, which is frequently used in vestibular research and treatment. For this, I analysed functional network connectivity in healthy participants. I found that short-term vestibular stimulation does not cause a cortical functional reorganisation, although a nociceptive stimulus, which was matched for the somatosensory component of this stimulation, led to a reorganisation. The fact that cortical reorganisation does not occur during exclusively vestibular stimulation may reflect subconscious nature of vestibular processing in that it does not induce a different internal brain state. On the medium-term time scale, I investigated whole-brain structural changes as a result of gravity. Astronauts that travel to space for extended periods of time experience several physiological symptoms also affecting the fluid exchange of the brain. To characterise if these fluid exchanges also affect size of the spaces around brain blood vessels (perivascular spaces), I developed a semi-automatic detection pipeline which requires only one type of structural MR image. I found that space travellers have enlarged perivascular spaces even before their mission, when compared to a control population. These spaces were to a small extend further increased shortly after a long duration space flight of 6 months. Astronaut training thus contributes to structural changes in the whole brain in combination with long-duration space flight. This further suggests that additional contextual factors such as sleep quality should be considered in the future. Overall, in my thesis I show that investigating the whole brain during different vestibular modulations provides additional and novel insights about the underlying neural processes. I found that long-term vestibular states have an impact on functional networks, whilst short-term vestibular modulations do not seem to impact functional network organisation. In addition, I quantified the structural impact of microgravity and astronaut training in the whole brain using a new analysis pipeline. In the future, I expect that new advancements in the field of neuroimaging analysis, such as high sampling of individuals and dynamic network analysis will advance the field. This will potentially also provide new means to monitor disease progression or intervention success

Relationship between migraine triggers, auras and treatment

Background: Migraine trigger factors are precipitating factors that can contribute to an attack by increasing the probability of a migraine occurring. For some migraineurs, the headache phase is preceded by a transient disturbance in neurological function (an aura). An aura could be visual or sensory in nature. There are medications that can be used to treat a migraine attack when it occurs (acute medication) and medication that can be used to reduce frequency and severity of migraine attacks (prophylactic medication). Objectives: The primary aim of the study was to identify if there was a relationship between migraine trigger factors, auras and treatment. Methods: The study was conducted in 2014 in Port Elizabeth and consisted of two self-administered questionnaire-based surveys, one for pharmacists and one for migraine patients. Migraine patient questionnaires were distributed to migraine patients who frequented pharmacies, physiotherapy practices and health shops. A total of 18 pharmacist questionnaires and 173 migraine patient questionnaires were analysed. Results: Experiencing an aura before a migraine attack was reported by 43.9% of respondents and only “sometimes” by 22.5% of respondents. Visual auras were experienced by 92.0% of respondents who indicated that they suffered from migraine with aura and sensory auras were experienced by 71.5% of respondents, with 62.8% of respondents experiencing both visual and sensory auras. Trigger factors were experienced by 89.0% of respondents. There was no statistical relationship between aura and trigger factors, but there was a statistical relationship between trigger factors and visual aura at the 5% level (Chi-square = 7.966, d.f. = 1, p-value = 0.005). Cramér’s V showed a small practical significance at 0.218. About 80.0% of respondents used over-the-counter (OTC) medication and only 12.6% used migraine specific medication to abort a migraine attack. There was no statistical relationship between aura (visual or sensory) and abortive medication. There was a statistical relationship between abortive medication and the presence of trigger factors (Chi-square = 8.775, d.f. = 3, p-value = 0.032). Cramér’s V showed a small practical significance at 0.244. There was no statistical relationship in the presence of trigger factors between aura and abortive medication. Conclusion: Migraine is a complex disease which affects people of all ages. There appears to be a statistical relationship between visual auras and trigger factors and between abortive medication and trigger factors. There was, however, no statistical relationship between aura and abortive medication in the presence of trigger factors. Further studies need to be conducted to substantiate these findings

Efficacy of Home Based Particle Repositioning Maneuver in Treatment of Posterior Canal Benign Paroxysmal Positional Vertigo

BACKGROUND: Benign paroxysmal positional vertigo (BPPV) is one of the most common causes of vertigo in patients visiting the outpatient department (OPD). Many patients find it difficult to visit the hospital numerous times for a standard Epley’s maneuver which has to be performed only by a specialist. OBJECTIVE: Our aim is to compare the efficacy of a home based particle repositioning procedure (HBPRP) with the standard Epley’s maneuver in treating patients with posterior canal BPPV. METHODS: This was a prospective non blinded randomized controlled study comparing two groups, where one group received the standard treatment and other received a new HBPRP. The vertigo scale, nystagmus duration during Hallpike test and frequency of vertigo, were documented on first, second and third visits. Complications if any were also noted during second and third visit. The parameters were compared in both the groups following the treatment in all visits. RESULTS: Thirty patients were randomized into 2 groups. There were 15 patients in each arm. Group 1 received Epley and group 2 received HBPRP. There was no significant difference in the baseline characteristics of patients like age, gender, co morbid illness in both groups. Statistical analysis showed that there was no difference in the reduction in vertigo scale, duration of nystagmus following Hallpike test, frequency of vertigo in both groups. CONCLUSIONS: This study showed that HBPRP is a safe and effective procedure and can be taught as a home based treatment for patients diagnosed with posterior canal BPPV