Transcutaneous Auricular Vagus Nerve Stimulation towards Visually Induced Motion Sickness Reduction: A Pilot Study.

Transcutaneous auricular vagus nerve stimulation (taVNS) is a novel neuromodulation application for vagal afferent stimulation. Owing to its non-invasive nature, taVNS is a potent therapeutic tool for a diverse array of diseases and disorders that ail us. Herein, we investigated taVNS-induced effects on neural activity of participants during visually induced motion sickness. 64-channel electroencephalography (EEG) recordings were obtained from 15 healthy participants in a randomized, within-subjects, cross-over design during sham and taVNS conditions. To assess motion sickness severity, we used the motion sickness assessment questionnaire (MSAQ). We observed that taVNS attenuated theta (4-8 Hz) brain activity in the right frontal, right parietal and occipital cortices when compared to sham condition. The total MSAQ scores, and central, peripheral and sopite MSAQ categorical scores were significantly lower after taVNS compared to sham. These findings reveal for the first time the potential therapeutic role of taVNS toward counter-motion sickness, and suggest that taVNS may be reliable in alleviating symptoms of motion sickness in real-time, non-pharmacologically.Clinical relevance- This suggests taVNS potential to offset motion sickness-induced nausea; which may be of translational value to counter e.g., chemotherapy-induced nausea.

Vibro-motor Reprocessing Therapy towards Managing Motion Sickness Reduction: Evidence from EEG.

This study examines the neural activities of participants undergoing vibro-motor reprocessing therapy (VRT) while experiencing motion sickness. We evaluated the efficacy of vibro-motor reprocessing therapy, a novel therapeutic technique based on eye movement desensitization and reprocessing (EMDR), in reducing motion sickness. Based on visually induced motion sickness in two sets of performed sessions, eight participants were exposed to VRT stimulation in a VRT/non-VRT setting. Simultaneously, brain activity changes were recorded using electroencephalography (EEG) at baseline and during stimulus exposure, and comparisons made across the VRT/non-VRT conditions. A significant reduction in the alpha (8-12 Hz) spectral power was observed in the frontal and occipital locations, consistent across all participants. Furthermore, significant reductions were also found in the frontal and occipital delta (0.5-4 Hz) and theta (4-8 Hz) spectral power frequency bands between non-VRT and VRT conditions (p < 0.05). Our results offer novel insights for a potential nonpharmacological treatment and attenuation of motion sickness. Furthermore, symptoms can be observed, and alleviated, in real-time using the reported techniques. Clinical relevance - Instead of using drugs to treat motion sickness, patients could safely use this VRT technique.

Molecular classification of the placebo effect in nausea.

In this proof-of-concept study, we tested whether placebo effects can be monitored and predicted by plasma proteins. In a randomized controlled design, 90 participants were exposed to a nauseating stimulus on two separate days and were randomly allocated to placebo treatment or no treatment on the second day. Significant placebo effects on nausea, motion sickness, and (in females) gastric activity could be verified. Using label-free tandem mass spectrometry, 74 differentially regulated proteins were identified as correlates of the placebo effect. Gene ontology (GO) enrichment analyses identified acute-phase proteins and microinflammatory proteins to be involved, and the identified GO signatures predicted day-adjusted scores of nausea indices in the placebo group. We also performed GO enrichment analyses of specific plasma proteins predictable by the experimental factors or their interactions and identified 'grooming behavior' as a prominent hit. Finally, Receiver Operator Characteristics (ROC) allowed to identify plasma proteins differentiating placebo responders from non-responders, comprising immunoglobulins and proteins involved in oxidation reduction processes and complement activation. Plasma proteomics is a promising tool to identify molecular correlates and predictors of the placebo effect in humans.

Effect of Acupuncture on the p38 Signaling Pathway in Several Nervous System Diseases: A Systematic Review.

Acupuncture is clinically used to treat various diseases and exerts positive local and systemic effects in several nervous system diseases. Advanced molecular and clinical studies have continually attempted to decipher the mechanisms underlying these effects of acupuncture. While a growing understanding of the pathophysiology underlying several nervous system diseases shows it to be related to inflammation and impair cell regeneration after ischemic events, the relationship between the therapeutic mechanism of acupuncture and the p38 MAPK signal pathway has yet to be elucidated. This review discusses the latest advancements in the identification of the effect of acupuncture on the p38 signaling pathway in several nervous system diseases. We electronically searched databases including PubMed, Embase, and the Cochrane Library from their inception to April 2020, using the following keywords alone or in various combinations: "acupuncture", "p38 MAPK pathway", "signaling", "stress response", "inflammation", "immune", "pain", "analgesic", "cerebral ischemic injury", "epilepsy", "Alzheimer's disease", "Parkinson's disease", "dementia", "degenerative", and "homeostasis". Manual acupuncture and electroacupuncture confer positive therapeutic effects by regulating proinflammatory cytokines, ion channels, scaffold proteins, and transcription factors including TRPV1/4, Nav, BDNF, and NADMR1; consequently, p38 regulates various phenomena including cell communication, remodeling, regeneration, and gene expression. In this review article, we found the most common acupoints for the relief of nervous system disorders including GV20, GV14, ST36, ST37, and LI4. Acupuncture exhibits dual regulatory functions of activating or inhibiting different p38 MAPK pathways, contributing to an overall improvement of clinical symptoms and function in several nervous system diseases.

Targeting TRPV1 to relieve motion sickness symptoms in mice by electroacupuncture and gene deletion.

Motion sickness (MS) is an acute disorder that occurs in healthy individuals worldwide regardless of gender, age, or ethnicity. Our study used a mouse model to rule out the effects of any psychological factors related to MS and EA. Subjects were randomly separated into four groups, namely the control group (Con), motion sickness inducing group (MS), mentioning sickness inducing with electroacupuncture treatment group (EA) and motion sickness inducing only in TRPV1 knockout mice group (TRPV1-/-). The consumption of kaolin, a non-nutrient substance, was measured as a behavior observed response of an emetic reflex in a murine model. This behavior is referred to as pica behavior. Our results showed that pica behavior was observed in the MS group. Moreover, kaolin consumption in the EA group decreased to the average baseline of the control group. A similar result was observed in TRPV1 null mice. We also observed an increase of TRPV1 and related molecules in the thalamus, hypothalamic and brain stem after MS stimulation and a significant decrease in the EA and TRPV1 null groups. This is the first study to demonstrate that TRPV1 pathways are possibly associated with mechanisms of MS, and can be attended through EA or TRPV1 genetic manipulation.

Acupuncture relieves motion sickness via the IRß-ERK1/2-dependent insulin receptor signalling pathway.

OBJECTIVE: Acupuncture has been widely used for the treatment of motion sickness (MS), but the underlying mechanisms are unclear. The aim of this research was to study the mechanism of acupuncture in the treatment of MS. METHODS: To observe the effects of acupuncture in the treatment of MS, 80 rats were randomised into five groups that were subjected to acceleration and either remained untreated (CTRL), or received restraint (REST), scopolamine (SCOP) or acupuncture at SP4 (sham) or PC6+ST36 (verum) acupuncture points. To study the mechanism underlying the effects of acupuncture in the treatment of MS, 48 rats were randomised into three groups: acupuncture+extracellular regulated protein kinases (ERK) 1/2 inhibitor (ERKinh), acupuncture+insulin receptor (IR) antagonist (IRant), and acupuncture+vehicle (VEH). After acceleration, the MS index (MSI) and spontaneous activity (SA) of the rats were recorded. Serum stress hormones, Fos-positive cells, c-fos mRNA in the vestibular nucleus, and IRß-, p-IRß-, ERK1/2- and p-ERK1/2-positive cells in the dorsal motor nucleus of the vagus nerve (DMV) were detected. RESULTS: After acceleration, MS symptoms in the PC6+ST36 and SCOP groups were reduced compared with the CTRL, REST, and SP4 groups. The number of p-IRß- and p-ERK1/2-positive cells and insulin levels were higher in the PC6+ST36 group than in the CTRL, REST, and SP4 groups. After ERK1/2 inhibitor and IR antagonist treatment, MS symptoms in the VEH group were lower than in the ERKinh and IRant groups. CONCLUSIONS: Our study demonstrates that acupuncture significantly alleviates MS through the IRß-ERK1/2-dependent insulin receptor signalling pathway in the DMV.

Effectiveness of a placebo intervention on visually induced nausea in women - A randomized controlled pilot study.

OBJECTIVE: Improvement of nausea by placebo interventions has recently been demonstrated in clinical trials and experimental settings. However, many questions regarding placebo effects on nausea remain unanswered. For example, nausea reduction in women could only be achieved when the placebo intervention was "enhanced" by conditioning, while men responded primarily to verbally suggested improvement. It is unclear whether these findings are generalizable or were due to situational variables. In this pilot study, we investigated the effects of sham acupuncture point stimulation and verbal suggestions on visually-induced nausea in a female population. METHODS: In a within-subjects design, 21 healthy female volunteers underwent both a placebo condition and a natural history condition (control condition) in a randomized order on two separate days. On both days, nausea was induced through optokinetic stimulation. On the placebo day, participants received sham acupuncture point stimulation together with positive verbal suggestions of nausea improvement. Expected and perceived nausea severity as well as symptoms of motion sickness were repeatedly assessed. RESULTS: Twenty participants completed both testing days. Participants developed significantly less nausea on the placebo day compared to the control day (p<0.001), and the effect size of placebo-induced nausea reduction was large (partial η2=0.71). Symptoms of motion sickness were also reduced (p=0.003). Expectation of nausea decreased following the placebo intervention as compared to no treatment (p=0.030), indicating successful expectancy manipulation. CONCLUSION: Sham acupuncture point stimulation combined with verbal suggestions induced a significant placebo effect on visually-induced nausea in women.

Sea State Green.

The series objective is to review various clinical conditions/ presentations, including the latest evidence on management, and to dispel common myths. In the process, core knowledge and management principles are enhanced. A clinical case will be presented. Cases will be drawn from real life but phrased in a context that is applicable to the Special Operations Forces (SOF) or tactical emergency medical support (TEMS) environment. Details will be presented in such a way that the reader can follow along and identify how they would manage the case clinically depending on their experience and environment situation. Commentary will be provided by currently serving military medical technicians. The medics and author will draw on their SOF experience to communicate relevant clinical concepts pertinent to different operational environments including SOF and TEMS. Commentary and input from active special op.

Diaphragmatic breathing and its effectiveness for the management of motion sickness.

BACKGROUND: Motion sickness is an unpleasant physiological state that may be controlled via nonpharmacological methods. Controlled breathing has been shown to maximize parasympathetic nervous system (PNS) tone and may have the ability to decrease motion sickness symptoms. METHODS: The effects of slow diaphragmatic breathing (DB) in a motion sickness-inducing environment were examined within motion sickness susceptible individuals. Subjects (N = 43) were assigned randomly to either an experimental group trained in slow DB or a control group breathing naturally at a normal pace. The experimental group was trained using a digital video that helped them pace their diaphragmatic breathing at six breaths/min. During the study, subjects viewed a virtual reality (VR) experience of a boat in rough seas for 10 min. Motion sickness ratings along with heart rate and respiration rate were collected before, during, and after the VR experience. RESULTS: Results indicated that the experimental group was able to decrease their breathing to eight breaths/min during the VR experience. This breathing rate was significantly slower than those in the control group. We found that DB subjects, compared to those in the control group, displayed significantly greater heart rate variability and reported feeling less motion sickness during exposure to the VR experience than those in the control group. DISCUSSION: Results indicate possible benefits of using slow DB techniques in a motion sickness inducing environment.

Use of controlled diaphragmatic breathing for the management of motion sickness in a virtual reality environment.

Evidence indicates that activation of the parasympathetic nervous system (PNS) suppresses physiological responses associated with motion sickness. Research also shows paced breathing increases PNS activation; the current study examines the use of paced diaphragmatic breathing (DB) training to quell motion sickness symptoms. Healthy participants (N = 60) were pre-screened for motion sickness susceptibility. Participants were then randomly assigned to either a control condition, focusing on environmental awareness, or to an experimental condition implementing paced DB. Following this, participants were exposed to a virtual reality (VR) motion sickness experience, while heart rate variability, breathing rate (RPM), and motion sickness ratings were collected. Results demonstrated participants in the DB condition had higher PNS activation and reported fewer motion sickness symptoms during the VR experience than the participants in the control condition. Results suggest that the DB protocol can be used to significantly increase PNS tone and decrease the development of motion sickness symptoms.

[Controlled observation of the efficacy on motion sickness in the prevention and treatment with jianpixingnao needling therapy].

OBJECTIVE: To verify the efficacy of Jianpi-xingniao needling therapy on prevention and treatment of motion sickness. METHODS: Sixty volunteers of motion sickness were randomized into an acupuncture group and a delayed acupuncture group, 30 cases in each one. In the acupuncture group, acupuncture was given at Baihui (GV 20), Sishencong (EX-HN 1), Neiguan (PC 6), Zusanli (ST 36) and Hegu (LI 4). The needles were retained for 20 min. The treatment was given twice a week and 10 treatments were required. In the delayed acupuncture group, acupuncture was postponed, meaning no acupuncture during observation stage. Graybel scale was adopted to observe the score of symptoms and physical signs of the subjects of motion sickness before and after intervention. The efficacy was compared between the two groups. RESULTS: Twenty-five cases in the acupuncture group and 22 cases in the delayed acupuncture group were included in the statistical analysis. The score of symptoms and physical signs of motion sickness was reduced significantly after treatment in the acupuncture group as compared with that before treatment (10.12 +/- 3.37 vs 0.92 +/- 0.40, P < 0.05). The score in the acupuncture group was lower apparently than that in the delayed acupuncture group (0.92 +/- 0.40 vs 9.86 +/- 2.53, P < 0.05). The difference was not significant before and after treatment in the self-comparison of the delayed acupuncture group (P > 0.05). The total effective rate was 96.0% (24/25) in the acupuncture group, which was significantly better than 0.0% (0/22) in the delayed acupuncture group (P < 0.01). CONCLUSION: Jianpixingniao needling therapy relieves the symptoms of motion sickness in the patients and achieves a better clinical efficacy.

Galvanic vestibular stimulation: a novel modulatory countermeasure for vestibular-associated movement disorders.

Motion sickness or kinetosis is the result of the abnormal neural output originated by visual, proprioceptive and vestibular mismatch, which reverses once the dysfunctional sensory information becomes coherent. The space adaptation syndrome or space sickness relates to motion sickness; it is considered to be due to yaw, pith, and roll coordinates mismatch. Several behavioural and pharmacological measures have been proposed to control these vestibular-associated movement disorders with no success. Galvanic vestibular stimulation has the potential of up-regulating disturbed sensory-motor mismatch originated by kinetosis and space sickness by modulating the GABA-related ion channels neural transmission in the inner ear. It improves the signal-to-noise ratio of the afferent proprioceptive volleys, which would ultimately modulate the motor output restoring the disordered gait, balance and human locomotion due to kinetosis, as well as the spatial disorientation generated by gravity transition.

Galvanic vestibular stimulation: a novel modulatory countermeasure for vestibular-associated movement disorders / Estimulacao galvanica vestibular para corrigir transtornos neurologicos associados a disfuncao vestibular

Motion sickness or kinetosis is the result of the abnormal neural output originated by visual, proprioceptive and vestibular mismatch, which reverses once the dysfunctional sensory information becomes coherent. The space adaptation syndrome or space sickness relates to motion sickness; it is considered to be due to yaw, pith, and roll coordinates mismatch. Several behavioural and pharmacological measures have been proposed to control these vestibular-associated movement disorders with no success. Galvanic vestibular stimulation has the potential of up-regulating disturbed sensory-motor mismatch originated by kinetosis and space sickness by modulating the GABA-related ion channels neural transmission in the inner ear. It improves the signal-to-noise ratio of the afferent proprioceptive volleys, which would ultimately modulate the motor output restoring the disordered gait, balance and human locomotion due to kinetosis, as well as the spatial disorientation generated by gravity transition.

A cinetose ou doença do movimento resulta de uma resposta neural anormal originada do desequilíbrio entre estímulos visuais, proprioceptivos e vestibulares, que melhora quando esse desequilíbrio é corrigido. A síndrome de adaptação espacial ou doença do espaço está relacionada à doença do movimento e é desencadeada por mudanças bruscas de direção, inclinação e rotação da cabeça. Têm sido propostas várias medidas comportamentais e farmacológicas para controlar esses transtornos do movimento associados com o sistema vestibular, mas sem sucesso. A estimulação galvânica vestibular pode regular o desequilíbrio sensitivo-motor causado pela cinetose e pela doença do espaço modulando os canais iônicos GABA, relacionados à transmissão de impulsos nervosos no ouvido interno. Essa estimulação melhora a relação sinal-ruído dos impulsos proprioceptivos que acabam modulando a resposta motora, restabelecendo o equilíbrio e a marcha, recuperando a desorientação espacial causada pelos diversos gradientes de gravidade.

Effects of transcutaneous electrical nerve stimulation on motion sickness induced by rotary chair: a crossover study.

OBJECTIVES: Motion sickness (MS) is evoked by the conflict among somatosensory, visual, and vestibular input. Some of the MS symptoms and signs are mediated by activation of the autonomic nervous system (ANS). Transcutaneous electrical nerve stimulation (TENS), a maneuver used for pain control, was found to influence cardiovascular responses through ANS reflex, and to enhance motor function, visuospatial abilities, postural control, and cognitive function. The purpose of the present study is to investigate the effects of TENS on MS. SUBJECTS AND DESIGN: Fifteen (15) healthy young men participated in a within-subjects crossover study. Each completed four test sessions (control, rotation, TENS, TENS+rotation) in randomized order. Rotary chair (120°/s) combined with pitch movement of the subject's head was used as a model to provoke MS. Whole rotation protocol consisted of 5 1-minute rotations, each separated by a 1-minute rest period. TENS protocol involved simultaneous electrical stimulation of posterior neck and Zusanli acupoint. OUTCOME MEASURES: Motion sickness susceptibility was rated on a standardized questionnaire (Motion Sickness Susceptibility Questionnaire). Motion sickness symptoms, blood pressure (BP), skin temperature, heart rate (HR), and heart rate variability (HRV) were measured. Saliva samples were collected to analyze the level of stress markers. Cognitive function was evaluated with d2 test prior to and after MS provocation. RESULTS: Spinning by itself significantly decreased task response speed and contraction. MS symptom scores, BP, as well as the sympathetic parameter of HRV increased progressively with MS provocation (p<0.05), but skin temperature decreased (p=0.023). Severity of MS symptoms significantly decreased with TENS intervention (p<0.05). After TENS treatment, subjects were able to concentrate better and showed fewer errors in a cognitive test. Salivary cortisol concentration significant decreased after TENS treatment. CONCLUSIONS: Sympathetic activity increased but parasympathetic activity decreased during MS. TENS was effective in reducing MS symptoms as well as alleviating cognitive impairment.

Could sound be used as a strategy for reducing symptoms of perceived motion sickness?

BACKGROUND: Working while exposed to motions, physically and psychologically affects a person. Traditionally, motion sickness symptom reduction has implied use of medication, which can lead to detrimental effects on performance. Non-pharmaceutical strategies, in turn, often require cognitive and perceptual attention. Hence, for people working in high demand environments where it is impossible to reallocate focus of attention, other strategies are called upon. The aim of the study was to investigate possible impact of a mitigation strategy on perceived motion sickness and psychophysiological responses, based on an artificial sound horizon compared with a non-positioned sound source. METHODS: Twenty-three healthy subjects were seated on a motion platform in an artificial sound horizon or in non-positioned sound, in random order with one week interval between the trials. Perceived motion sickness (Mal), maximum duration of exposure (ST), skin conductance, blood volume pulse, temperature, respiration rate, eye movements and heart rate were measured continuously throughout the trials. RESULTS: Mal scores increased over time in both sound conditions, but the artificial sound horizon, applied as a mitigation strategy for perceived motion sickness, showed no significant effect on Mal scores or ST. The number of fixations increased with time in the non-positioned sound condition. Moreover, fixation time was longer in the non-positioned sound condition compared with sound horizon, indicating that the subjects used more time to fixate and, hence, assumingly made fewer saccades. CONCLUSION: A subliminally presented artificial sound horizon did not significantly affect perceived motion sickness, psychophysiological variables or the time the subjects endured the motion sickness triggering stimuli. The number of fixations and fixation times increased over time in the non-positioned sound condition.

Effects of gastric electrical stimulation with short pulses and long pulses on gastric dysrhythmia and signs induced by vasopressin in dogs.

AIMS: This study was to investigate the effect of gastric electrical stimulation (GES) with short pulses, long pulses, short-pulse trains or long-pulse trains on gastric dysrhythmia and motion-sickness signs induced by vasopressin. METHODS: Seven male beagle dogs implanted with four pairs of electrodes on gastric serosa were studied. The study was performed in six sessions in a randomized order. In session 1 or 2, either saline or vasopressin was infused without GES. In session 3, 4, 5 and 6, GES with short pulses, long pulses, trains of short pulses or trains of long pulses was performed before and during vasopressin infusion. Gastric slow waves and motion-sickness signs were recorded in each session. RESULTS: (1) Vasopressin induced gastric dysrhythmia and motion sickness-like signs (ANOVA, P < 0.001). (2) GES with short pulses or trains of short pulses was capable of preventing vasopressin-induced emetic response (P < 0.001), but did not normalize gastric dysrhythmia. (3) GES with long pulses or trains of long pulses was able to normalize gastric dysrhythmia induced by vasopressin (P < 0.001), but showed no effects on vasopressin-induced motion-sickness signs. CONCLUSION: GES with short pulses or trains of short pulses prevents vasopressin-induced emetic response with no improvement in gastric dysrhythmia. GES with long pulses or trains of long pulses normalizes gastric dysrhythmia induced by vasopressin with no effects on signs.

[Orientation taping magnetic granules at auricular points and Neiguan (PC 6) for prevention and treatment of 102 cases of motion sickness].

OBJECTIVE: To observe therapeutic effect of orientation taping magnetic granules at auricular points and Neiguan (PC 6) on motion sickness. METHODS: All 200 cases of motion sickness were divided into a treatment group (n = 102) and a control group (n = 98). The treatment group were treated with orientation taping magnetic granules at auricular points and Neiguan (PC 6), and the control group with oral administration of theohydramine. RESULTS: There was a significant difference between the two groups in the total effective rate (P < 0.05), and clinical symptoms disappeared more rapidly in the treatment group as compared with the control group (P < 0.05). The therapeutic effect in the mild and moderate patients of the treatment group was better than that of the control group, and there was no significant difference in the therapeutic effect for the severe patients between the two groups. In the treatment group, the therapeutic effect of the mild patient was the best, the moderate patient was next and the severe patient was the worst, with a very significant difference (P < 0.005). CONCLUSION: Orientation Taping magnetic granules at auricular points and Neiguan (PC 6) has an obvious therapeutic effect on motion sickness, with less adverse reactions.