Thesis (M.S.)--California Polytechnic State University, 2009. / Mode of access: Internet. Title from PDF title page; viewed on Jan. 20, 2010. Major professor: Dr. Lynne Slivovsky. "Presented to the faculty of the College of Engineering, California Polytechnic State University." "In partial fulfillment of the requirements for the degree [of] Master of Science in Electrical Engineering." "July 2009." Includes bibliographical references (p. 102-104).

Migraine, a neurovascular disorder, is associated with disturbances in brain stem activity during attacks. Interictal persistence of these disturbances might increase vulnerability to recurrent attacks of migraine. To explore this possibility, effects of motion sickness and pain on migrainous symptoms and extracranial vascular reponses were investigated in 27 migraine sufferers in the headache-free interval, and 23 healthy age/sex matched controls. Symptoms of migraine and motion sickness are remarkably similar. As both maladies involve reflexes that relay in the brain stem, they most probably share the same neural circuitry. Furthermore, migraineurs are usually susceptible to motion sickness and, conversely, motion sickness-prone individuals commonly experience migraine. Participants in the present study were exposed to optokinetic stimulation (OKS), a well-established way of inducing symptoms of motion sickness in susceptible individuals. Sensitivity to painful stimulation of the head and hand was also explored. Head pain is a hallmark of a migraine attack and cutaneous allodynia has been observed elsewhere in the body during attacks. The trigeminal nerve is associated with head pain in migraine, and trigeminal activity evokes reflexes that relay in the brain stem. To stimulate the trigeminal nerve, ice was applied to the temple. To stimulate nociceptors elsewhere in the body the participant immersed their fingers and palm in ice-water. Procedures used in this study were physically stressful and probably psychologically stressful. The impact of stress in relation to the development of symptomatic and vascular responses, particularly anticipatory stress-responses, was explored. This research involved one central experiment that consisted of six experimental conditions. On separate occasions participants were exposed to optokinetic stimulation and painful stimulation of the head or limb, individually and in combination. In migraine sufferers, symptomatic responses were enhanced during all procedures involving OKS and during temple pain after OKS, in the presence of residual motion sickness. During trigeminal stimulation independent of OKS, headache initially developed followed by nausea as the procedure progressed. In contrast, symptoms barely developed in controls during any of the six procedures except for slight dizziness, self-motion and visual-illusion during conditions involving OKS, and slight nausea when the temple was painfully stimulated during OKS and during OKS alone. Trigeminal stimulation during OKS intensified nausea and headache in migraine sufferers compared to during OKS alone or limb pain during OKS. However, the remaining symptomatic ratings were not affected by temple pain during OKS, suggesting a specific association between nausea and head pain. It may be that these cardinal symptoms compound one another during a migraine attack. Enhanced symptomatic responses in migraine sufferers during the headache interval may indicate activation of hypersensitive neural pathways that mediate symptoms of motion sickness or migraine. Migraineurs found procedures generally more unpleasant, and ice-induced pain ratings more intense and unpleasant, than controls, which may further indicate hyperexcitable nociception in this group, or a difference in their criterion of discomfort. Vascular responses, particularly during OKS alone, and during painful stimulation independent of OKS, were greater in migraine sufferers than in controls. The added stress of painful stimulation during OKS appeared to boost facial blood flow in controls to approach levels obtained in migraine sufferers. Enhanced vasodilatation was observed in migraineurs prior to painful stimulation, presumably due to anticipatory anxiety. For both groups ipsilateral vascular responses were greater than contralateral responses when the hand was painfully stimulated. During limb pain before OKS asymmetry was minimal in migraine sufferers but more apparent in controls. An enhanced stress response in migraineurs may have drawn ipsilateral and contralateral responses closer together. The development of symptoms during the procedures of this study provides an insight into how symptoms might develop sequentially in a migraine attack. Once the headache is in motion, nausea and headache may mutually exacerbate one another. In turn, trigemino-vascular responses and stress appear to be associated with the migraine crisis. Given the interactive nature of symptomatic, vascular, and stress responses, it may be more effective to target multiple, rather than individual, symptoms, in prophylactic or acute chemical and psychological interventions.

Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002. / Includes bibliographical references (leaves 139-146). Also available in electronic version. Access restricted to campus users.

Motion sickness has been a significant obstacle for the development of Virtual Reality technology since the beginning of its existence. Research has shown that audio can be used to reduce motion sickness in VR. It has also been proven that binaural ambisonic audio can enhance a player’s feelings of immersion and spatial presence, which is known to correlate negatively with motion sickness. This study aims to determine if the application of spatialized binaural ambisonic audio in VR environments can make users feel less motion sick, by enhancing the feeling of presence, compared to environments that utilize regular stereo sound. To validate our hypothesis, two versions of the same VR environment were created: one with binaural ambisonic audio, and another with regular stereo audio. The data was collected with surveys that included both motion sickness-related and experience-related questions. The results indicate that binaural ambisonic audio helped to reduce motion sickness compared to regular stereo audio, even though testers did not show any clear preference for one type of sound over another. / Rörelsesjuka har utgjort ett allvarligt hinder för utveckling av virtual reality-teknologi  (VR) från dess tidigaste utvecklingsfas. Forskning har visat att ljud kan användas för reducering av rörelsesjuka i VR. Det har också påvisats att binauralt ambisoniskt ljud kan förstärka spelarens känsla av immersion och spatial närvaro, som har en negativ korrelation med rörelsesjuka. Denna studies syfte är att avgöra om  användning av spatialt binauralt ambisoniskt ljud i VR-miljö kan reducera användarens rörelsesjuka, genom att förstärka känslan av närvaro, till skillnad från miljöer där rådande stereoteknologi används. Hypotesen testades genom att två  versioner av samma VR-miljö skapades: ett med binauralt ambisonisk ljud och ett  med vedertaget stereoljud. Insamlad data genom ett frågeformulär inkluderade även frågor rörande rörelsesjuka och tidigare erfarenhet av VR. Resultatet indikerar att binauralt ambisoniskt ljud reducerar rörelsesjuka, till skillnad från stereoljud, trots att testpersonerna inte visade på en tydlig preferens för den ena eller den andra ljudtypen.

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The present research attempted to use display design as a means to mitigate the occurrence and severity of symptoms of motion sickness and increase performance due to reduced “general effects” in an uncoupled motion environment. Specifically, several visual display manipulations of a 360° indirect vision system were implemented during a target detection task while participants were concurrently immersed in a motion simulator that mimicked off-road terrain which was completely separate from the target detection route. Results of a multiple regression analysis determined that the Dual Banners display incorporating an artificial horizon (i.e., AH Dual Banners) and perceived attentional control significantly contributed to the outcome of total severity of motion sickness, as measured by the Simulator Sickness Questionnaire (SSQ). Altogether, 33.6% (adjusted) of the variability in Total Severity was predicted by the variables used in the model. Objective measures were assessed prior to, during and after uncoupled motion. These tests involved performance while immersed in the environment (i.e., target detection and situation awareness), as well as postural stability and cognitive and visual assessment tests (i.e., Grammatical Reasoning and Manikin) both before and after immersion. Response time to Grammatical Reasoning actually decreased after uncoupled motion. However, this was the only significant difference of all the performance measures. Assessment of subjective workload (as measured by NASA-TLX) determined that participants in Dual Banners display conditions had a significantly lower level of perceived physical demand than those with Completely Separated display designs. Further, perceived iv temporal demand was lower for participants exposed to conditions incorporating an artificial horizon. Subjective sickness (SSQ Total Severity, Nausea, Oculomotor and Disorientation) was evaluated using non-parametric tests and confirmed that the AH Dual Banners display had significantly lower Total Severity scores than the Completely Separated display with no artificial horizon (i.e., NoAH Completely Separated). Oculomotor scores were also significantly different for these two conditions, with lower scores associated with AH Dual Banners. The NoAH Completely Separated condition also had marginally higher oculomotor scores when compared to the Completely Separated display incorporating the artificial horizon (AH Completely Separated). There were no significant differences of sickness symptoms or severity (measured by self-assessment, postural stability, and cognitive and visual tests) between display designs 30- and 60-minutes post-exposure. Further, 30- and 60- minute post measures were not significantly different from baseline scores, suggesting that aftereffects were not present up to 60 minutes post-exposure. It was concluded that incorporating an artificial horizon onto the Dual Banners display will be beneficial in mitigating symptoms of motion sickness in manned ground vehicles using 360° indirect vision systems. Screening for perceived attentional control will also be advantageous in situations where selection is possible. However, caution must be made in generalizing these results to missions under terrain or vehicle speed different than what is used for this study, as well as those that include a longer immersion time.

Carbody tilting is today a mature and inexpensive technology allowing higher speeds in curves and thus reduced travel time. The technology is accepted by most train operators, but a limited set of issues still holding back the full potential of tilting trains. The present study identifies and report on these issues in the first of two parts in this thesis. The second part is dedicated to analysis of some of the identified issues. The first part contains Chapters 2 to 5 and the second Chapters 6 to 12 where also the conclusions of the present study are given. Chapters 2 and 3 are related to the tilting train and the interaction between track and vehicle. Cross-wind stability is identified as critical for high-speed tilting trains. Limitation of the permissible speed in curves at high speed may be needed, reducing the benefit of tilting trains at very high speed. Track shift forces can also be safety critical for tilting vehicles at high speed. An improved track standard must be considered for high speed curving. Chapters 4 and 5 cover motion sickness knowledge, which may be important for the competitiveness of tilting trains. However, reduced risk of motion sickness may be contradictory to comfort in a traditional sense, one aspect can not be considered without also considering the other. One pure motion is not the likely cause to the motion sickness experienced in motion trains. A combination of motions is much more provocative and much more likely the cause. It is also likely that head rotations contribute as these may be performed at much higher motion amplitudes than performed by the train. Chapter 6 deals with services suitable for tilting trains. An analysis shows relations between cant deficiency, top speed, tractive performance and running times for a tilting train. About 9% running time may be gained on the Swedish line Stockholm – Gothenburg (457 km) if cant deficiency, top speed and tractive performance are improved compared with existing tilting trains. One interesting conclusion is that a non-tilting very high-speed train (280 km/h) will have longer running times than a tilting train with today’s maximum speed and tractive power. This statement is independent of top speed and tractive power of the non-tilting vehicle. Chapters 7 to 9 describe motion sickness tests made on-track within the EU-funded research project Fast And Comfortable Trains (FACT). An analysis is made showing correlation between vertical acceleration and motion sickness. However, vertical acceleration could not be pointed out as the cause to motion sickness as the correlation between vertical acceleration and several other motions are strong. Chapter 10 reports on design of track geometry. Guidelines for design of track cant are given optimising the counteracting requirements on comfort in non-tilting trains and risk of motion sickness in tilting trains. The guidelines are finally compared with the applied track cant on the Swedish line Stockholm – Gothenburg. Also transition curves and vertical track geometry are shortly discussed. Chapters 11 and 12 discusses the analysis, draws conclusions on the findings and gives proposals of further research within the present area. / QC 20101119

No / The aim of the present study was to investigate an opioid receptor involvement in the adaptation response to motion sickness in Suncus murinus. Different groups of animals were treated intraperitoneally with either saline, morphine (0.1 and 1.0 mg/kg), naloxone (1.0, 10.0 and 5.0 mg/kg) or a combination of naloxone plus morphine in the absence or 30 min prior to a horizontal motion stimulus of I Hz and 40 mm amplitude. For the study of adaptation, different groups received saline on the first trial, and in subsequent trials (every 2 days) they received either saline, naloxone (1.0 and 10.0 mg/kg, ip) or morphine (0.1 mg/kg, ip) 30 min prior to the motion stimulus. Pretreatment with morphine caused a dose-related reduction in emesis induced by a single challenge to a motion stimulus. Pretreatment with naloxone alone did not induce emesis in its own right nor did it modify emesis induced by a single challenge to a motion stimulus. However, pretreatment with naloxone (5.0 mg/kg, ip) revealed an emetic response to morphine (P<.001) (1.0 mg/kg, ip) and antagonised the reduction of motion sickness induced by morphine. In animals that received saline or naloxone (1.0 mg/kg), a motion stimulus inducing emesis decreased the responsiveness of animals to a second and subsequent motion stimulus challenge when applied every 2 days for 11 trials. However, the animals receiving naloxone 10.0 mg/kg prior to the second and subsequent challenges showed no significant reduction in the intensity of emesis compared to the first trial. The data are revealing of an emetic potential of morphine when administered in the presence of a naloxone pretreatment. The administration of naloxone is also revealing of an additional inhibitory opioid system whose activation by endogenous opioid(s) may play a role in the adaptation to motion sickness on repeated challenge in S. murinus.

Symptoms after surgery and anaesthesia influence the patient´s ability to resume daily activities. If postoperative symptoms are controlled rehabilitation may be accelerated. The aims of this dissertation were to identify disturbing symptoms reported by patients after gynaecological surgery, to investigate what effect prohylactic treatment with antiemetics has on these symptoms and whether or not sensory simulation of the P6-acupressure has an effect on postoperative nausea and vomiting (PONV) and motion sickness. Methods: Total 1138 women participated in three clinical trials (Studies I, II, III) and one experimental study (Study IV). A questionnaire investigating postoperative symptoms was constructed and validated. The questionnaire was used in a prospective, consecutive, doubleblind, randomised, multicentre, and controlled study to identify incidence, and intensity of postoperative symptoms and the effect of common antiemetics (droperidol and granisetron) (Study III). The patients were followed for 24 h. In two studies (I, II) P6-acupressure was compared (prospective, double-blind, ransomised, controlled) with placebo acupressure and a reference group where the effect on PONV was followed over 24 h. The effect of P6-acupressure and placebo acupressure on motion sickness induced by a nauseogenic motion challenge was studied (Study III). Results: A high incidence and severity of postoperative symptoms were found after gynaecological surgery in a group with a high risk (&gt;30%) for PONV. Sixty-four per cent (107/165) of the patients experienced disturbing symptoms after surgery and 46 % (76/165) scored their symptoms as moderate to very severe. Fourty-eight per cent (79/165) had two or more symptoms. A higher incidence of symptoms were reported in the groups with prophylactic treatment, granisetron 74% (123/165) and droperidol 80% (133/165) compared to the control group 41% (69/165) (P &lt;0.05). The relative risk reduction for PONV with granisetron or droperidol prophylaxis is 27% respective 22%. The relative risk increase for headache is 63% after granisetron, and 44% for difficulty with accommodation after droperidol. Less PONV was seen after P6-acupressure, 33% (44/135) compared to reference group 46% (63/136) (p = 0.019), number needed to treat (NNT) was 7 [95% confidence interval (CI) 4- 6]. When comparing laparoscopic and vaginal surgery (subgroup analysis) the main effect was in the vaginal group (day-case surgery), 36% (27/75) in the reference group to 27% (23/86) in the placebo group and to 20% (17/84) in the P6-acupressure group, (P = 0.017), NNT for the vaginal group was 6 [95% CI 3-18]. P6-acupressure increased time to nausea after a laboratory motion challenge and reduced the total number of symptoms reported (p &lt;0.009). Conclusions: There is no clinical efficacy in the form of reduced postoperative symptoms after prophylactic antiemetics (droperidol and granisetron) in females with a high risk (&gt;30%) for PONV undergoing gynaecological surgery. P6-acupressure reduces the incidence of PONV after gynaecological surgery in females with a high (&gt;30%) risk for PONV. The effect seems to be most prominent after vaginal surgery. P6-acupressure increased tolerance to experimental nausogenic stimuli and reduced the total number of symptoms reported in females with a history of motion sickness. / On the day of the public defence the status of article IV was: Submitted.

Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 4 uppsatser.