Motion Sickness: Recent Advances and Emerging Insights

Table 1. Major Risk Factors Associated with Motion Sickness

3. Etiology and Pathophysiology

A complicated neurophysiological condition known as "motion sickness" arises when the central nervous system is unable to integrate contradicting sensory data about movement and body position. Motion sickness is caused by the combination of vestibular, ocular, and somatosensory inputs that become incongruent during actual or perceived motion rather than by a single pathogenic process.^[17] The central autonomic pathways that cause the typical symptoms of nausea, vomiting, dizziness, pallor, cold sweats, and postural instability are activated by this sensory discordance. The sensory conflict (neural mismatch) theory, which is backed by a wealth of experimental and clinical data, continues to be the most widely accepted explanation for the disorder despite the fact that several theories have been put forth.

Fig:1 Pathophysiology of Motion Sickness

3.1 Etiology of Motion Sickness

Conditions where visual, vestibular, and proprioceptive signals send contradictory messages about bodily movement are the main cause of motion sickness. These sensory systems work together to preserve postural equilibrium, gaze stability, and spatial orientation under normal physiological conditions. However, disparities between these sensory inputs surpass the central nervous system's ability to adjust when exposed to atypical or repetitive motion, resulting in the development of motion sickness.^[18]

Traditional examples include utilizing electronics or reading while in a moving car. In these circumstances, the vestibular apparatus detects constant acceleration and deceleration while the eyes experience a somewhat fixed visual environment. On the other hand, despite the lack of comparable vestibular stimulation, users of immersive virtual reality systems feel optically produced motion. Traveling by sea, flying, going on amusement rides, going into space, and driving an autonomous vehicle all involve similar sensory conflicts that are distinct expressions of the same underlying neurophysiological process.^[19]

The development of symptoms is also greatly influenced by vehicle dynamics. Vestibular stimulation is increased and sensory conflict is made worse by low-frequency oscillatory motion (0.1–0.5 Hz), repeated linear acceleration, angular rotation, vibration, braking, cornering, and erratic direction changes. Visual-vestibular mismatch is further exacerbated by passenger activities that call for prolonged visual attention, such as reading, using a laptop, or using a smartphone. Motion sickness in autonomous vehicles has been linked to both higher interest in non-driving activity and the inability to predict vehicle movements.^[19]

Numerous biological and environmental factors affect an individual's sensitivity. The threshold for symptom development is influenced by a number of factors, including age, sex, genetic background, vestibular problems, migraine, anxiety, sleep deprivation, exhaustion, and prior motion sickness experiences. Motion sickness is not directly caused by these factors, but they do affect autonomic response and central sensory integration, which affects the intensity of symptoms.^[19]

3.2 Sensory Conflict Theory

Motion sickness is still mostly explained by the sensory conflict theory, which was first put forth by Reason and Brand. This concept states that the brain constantly contrasts internal representations of expected body motion created by prior experiences with incoming sensory data. When real sensory signals significantly deviate from these anticipated patterns, a neuronal mismatch results, leading to motion sickness.^[21]

Head acceleration is detected by the vestibular apparatus, and body orientation and ambient motion are detected by the visual system. Information about limb position and movement is simultaneously transmitted by proprioceptors found in muscles and joints ^[22]. In order to preserve balance and spatial direction, these signals are normally incorporated within the vestibular nuclei, cerebellum, and higher cerebral centers. However, differences between these sensory modalities trigger the brainstem autonomic center during provocative motion, which ultimately results in nausea and vomiting.
This theory is the most comprehensive framework now available because it covers almost all types of motion sickness, such as seasickness, airsickness, simulator sickness, cybersickness, and space motion sickness. ^[23]

3.3 Vestibular Mechanisms

As the primary sensory organ in charge of motion perception, the vestibular system is crucial to the pathophysiology of motion sickness. It is made up of the otolith organs (utricle and saccule), which react to linear acceleration and gravitational forces, and the three semicircular canals, which sense rotational acceleration.[24]
Vestibular hair cells transform mechanical displacement during motion into neurological signals that are sent to the vestibular nuclei of the brainstem via the vestibular nerve. These nuclei have significant communication with the hypothalamus, reticular formation, cerebellum, ocular motor nuclei, and autonomic centers that regulate the gastrointestinal and cardiovascular systems.

The vestibular velocity storage system, a neuronal network that prolongs vestibular reactions after stopping head movement, is one significant mechanism linked to motion sickness. Because chronic vestibular activity increases sensory mismatch, people with longer velocity-storage time constants are more susceptible ^[24]. On the other hand, near-total resistance to motion sickness is conferred by total bilateral vestibular failure, underscoring the critical significance of vestibular input.

3.4 Visual–Vestibular Interaction

Continuous integration of vestibular and visual information is necessary for successful balance maintenance. While vestibular receptors track head movement and acceleration, visual signals offer external spatial reference ^[25]. One of the most potent causes of motion sickness is conflict between these sensory systems.
Motion sickness caused by visual stimuli is best illustrated by virtual reality settings. Strong sensory conflict results from head-mounted displays that produce captivating visual impressions of movement without matching vestibular stimulation. The severity of symptoms is greatly influenced by variables such display delay, field of view, frame rate, stereoscopic rendering, and head-tracking precision. Vestibular signals that are inconsistent with eye fixation on fixed items like books or smartphone screens are also produced by repetitive acceleration and deceleration during road travel.^[26]

3.5 Central Neural Integration

A dispersed neuronal network that extends well beyond the vestibular region is involved in motion sickness. The vestibular nuclei, cerebellum, thalamus, anterior cingulate cortex, insular cortex, hypothalamus, and brainstem autonomic centers all integrate sensory data. Because they trigger the emetic reflex and coordinate autonomic responses, the nucleus tractus solitarius (NTS) and region postrema are especially significant.^[27]
These core pathways are triggered by sensory mismatch, which increases parasympathetic activity and triggers complicated sympathetic reactions that result in pallor, perspiration, salivation, gastric dysrhythmia, and vomiting. The correlation between anxiety and the intensity of symptoms may be explained by the participation of cortical regions involved in motion perception, emotional processing, and interoceptive awareness, according to functional neuroimaging studies.^[28]

3.6 Neurotransmitter Systems

Multiple neurotransmitter systems contribute to the development of motion sickness

One of the main mediators in vestibular-autonomic pathways is acetylcholine, which explains why muscarinic receptor antagonists like scopolamine have such high clinical efficacy. Additionally, histamine is crucial for vestibular signal transmission, which explains why first-generation antihistamines are so widely used.^[29]

While serotonin affects gastrointestinal motility and emesis through interactions with 5-HT receptors, dopamine mainly contributes to activation of the chemoreceptor trigger zone and modulation of nausea pathways. Additionally, there is growing evidence that substance P acts through neurokinin-1 (NK1) receptors, specifically in the area postrema and nucleus tractus solitarius. These discoveries have prompted the creation of NK1 receptor antagonists, such as tradipitant, which constitute a new therapeutic strategy.
Although more research is needed to determine their precise functions, other neuromodulators such as glutamate, endocannabinoids, and γ-aminobutyric acid (GABA) are increasingly acknowledged as regulators of vestibular adaptation and autonomic integration.^[30]

3.7 Autonomic and Gastrointestinal Responses

The distinctive autonomic symptoms of motion sickness are caused by activation of vestibular-autonomic circuits. Yawning, pallor, cold sweats, increased salivation, flushing of the face, and changes in heart rate variability are some of the early signs. Vomiting, nausea, and stomach discomfort follow progressive autonomic activation.

Abnormal stomach myoelectrical activity, delayed gastric emptying, and disruption of normal gastric slow waves are the mechanisms behind gastrointestinal disorders. Motion-induced nausea has also been linked to elevated plasma vasopressin levels, indicating endocrine involvement in the development of symptoms. High-fat meals consumed prior to travel further impede stomach emptying and may exacerbate symptoms. [31]

3.8 Postural Instability Theory

The postural instability theory offers an alternative viewpoint, even if the sensory conflict theory is still the most popular explanation. According to this theory, motion sickness develops after a protracted inability to keep a steady position. This paradigm states that persistent body sway instability indicates poor multisensory integration and foretells the emergence of following symptoms.

According to experimental research, people who are prone to motion sickness frequently show decreased postural control and greater center-of-pressure displacement prior to feeling unwell. Postural instability is probably a significant supplementary mechanism that interacts with sensory conflict throughout the development of symptoms, even if it cannot account for all types of motion sickness on its own [32]

3.9 Integrated Pathophysiological Model

According to available data, motion sickness is not caused by a single isolated mechanism but rather by dynamic interactions between sensory conflict, vestibular processing, central neuronal integration, autonomic activation, neurotransmitter signalling, and gastrointestinal dysfunction. The distinctive clinical manifestations are eventually produced by the convergence of these interrelated pathways on brainstem emetic centres. It is anticipated that further developments in neuroimaging, vestibular physiology, computational neuroscience, and molecular pharmacology will improve this integrated model and make it easier to create focused therapeutic interventions..^[33]

Table 2. Principal Mechanisms Involved in Motion Sickness

4. Clinical Manifestations and Diagnosis

A variety of autonomic, gastrointestinal, neurological, and behavioral symptoms that appear during or soon after exposure to provocative motion stimuli are the hallmarks of motion sickness. A distinctive history of symptom development in connection with actual or perceived motion serves as the primary basis for the clinical diagnosis of the illness.[34] Accurate diagnosis and severity evaluation are made possible by standardized symptom assessment tools and rigorous exclusion of other vestibular or neurological illnesses, even though no single laboratory or imaging study can prove motion sickness.

4.1 Clinical Manifestations

The degree, length, and frequency of motion exposure, as well as an individual's vulnerability, all influence how motion sickness manifests clinically. If exposure persists, symptoms often develop gradually and go through several stages, starting with mild autonomic reactions and progressing to severe gastrointestinal symptoms.[34]

Initial symptoms include generalized discomfort, tiredness, yawning, face pallor, cold chills, excessive salivation, epigastric awareness, and mild dizziness. Since these prodromal symptoms show that autonomic circuits are activated before nausea manifests, they present an opportunity for early therapy. The traditional symptoms of prolonged exposure to provocative motion include headache, nausea, vomiting, dizziness, vertigo, postural instability, impaired vision, exhaustion, and diminished focus. Increased sensitivity to smells, stomach pain, anorexia, and poor cognitive function are all common complaints among patients [35]. Severe vomiting can lead to electrolyte imbalance, dehydration, and severe functional impairment.

The stimulating environment affects how severe the symptoms are. While road travel typically causes symptoms during activities requiring visual attention, such reading or using a smartphone, sea travel frequently results in chronic nausea and vomiting due to continual oscillatory motion. Although turbulence is still a known trigger, air travel typically results in milder symptoms due to smoother motion profiles. On the other hand, visually induced motion sickness, also known as cybersickness or simulator sickness, frequently manifests as noticeable dizziness, visual discomfort, eye strain, headache, disorientation, and decreased balance during virtual reality or simulator exposure.[36]

Additionally, motion sickness causes quantifiable physiological changes. Heart rate variability, skin conductance, respiration rate, gastric myoelectrical activity, blood pressure, and pupillary responses have all been shown to alter with the onset of symptoms in experimental investigations. These physiological alterations, which are indicative of autonomic nervous system activation, have emerged as significant biomarkers in experimental studies examining objective indicators of the intensity of motion sickness [37].

4.2 Clinical Evaluation

A thorough clinical history that emphasizes the temporal correlation between the onset of symptoms and motion exposure is the first step in the diagnosis process. It is important to gather information about the mode of transportation, length of exposure, symptom progression, prior episodes, family history, medication use, vestibular problems, migraine, anxiety, and occupational exposure. The diagnosis is aided by the identification of triggering variables, such as reading while traveling, using virtual reality, traveling in an autonomous car, or going on amusement rides.^[38]

Although a physical examination is usually normal in between episodes, it is nonetheless necessary to rule out other possible causes of vertigo, nausea, or dizziness. Patients may experience pallor, diaphoresis, increased salivation, an unsteady stride, and minor postural instability during symptomatic times. When unusual features are present, a thorough neurological examination, cranial nerve assessment, cerebellar function testing, vestibulo-ocular reflex evaluation, and otological examination should be carried out.^[17]

4.3 Diagnostic Assessment Tools

A number of validated questionnaires have been developed to measure symptom severity, track therapy response, and support research, even though diagnosis is essentially clinical.[39]

The Motion Sickness Assessment Questionnaire (MSAQ)

One of the most extensively used tools for assessing motion sickness is the Motion Sickness Assessment Questionnaire (MSAQ). It is made up of several questions that evaluate symptoms connected to the gastrointestinal tract, central nervous system, peripheral autonomic nervous system, and sopite. The MSAQ is useful for both clinical research and therapeutic monitoring since it offers a multidimensional assessment of symptom load, in contrast to previous symptom scales that mainly focused on nausea and vomiting.^[40]

Simulator Sickness Questionnaire (SSQ)

The Simulator Sickness Questionnaire (SSQ) was originally developed for evaluating visually induced motion sickness associated with flight simulators and has since become the standard assessment tool for virtual reality research. The questionnaire measures three principal symptom domains: • Nausea • Oculomotor disturbance • Disorientation The SSQ is particularly useful for assessing cybersickness in virtual reality, augmented reality, mixed reality, and autonomous vehicle simulation studies

 Motion Sickness Susceptibility Questionnaire (MSSQ)

The Motion Sickness Susceptibility Questionnaire (MSSQ) estimates an individual's lifetime susceptibility by evaluating previous experiences across different

 modes of transportation during childhood and adulthood. The instrument is commonly employed in epidemiological investigations and experimental studies to identify high-risk individuals before motion exposure.

4.4 Emerging Objective Biomarkers

Current research aims to complement subjective symptom questionnaires with objective physiological measurements capable of predicting symptom onset before severe nausea develops. Several biomarkers have demonstrated promising diagnostic potential, including: Heart rate variability, Electrodermal (skin conductance) activity,  Gastric myoelectrical recordings (Electro gastrography), Electroencephalography (EEG) Functional near-infrared spectroscopy (FNIRS), Eye-tracking parameters, Pupillary dynamics, Respiratory variability, Wearable biosensor-derived autonomic indices Machine learning algorithms integrating these physiological signals have shown encouraging accuracy for predicting motion sickness susceptibility in aviation, autonomous driving, and virtual reality applications. Although these technologies remain largely investigational, they represent an important step toward personalized prevention strategies.[41]

4.5 Differential Diagnosis

Several medical conditions may mimic motion sickness and should be excluded when symptoms occur independently of motion exposure or present with atypical neurological findings.[42]

 Common differential diagnoses include:

Recognition of these conditions is essential because management strategies differ substantially from those used for motion sickness.

4.6 Diagnostic Challenges and Future Directions

Despite considerable advances in understanding motion sickness, diagnosis remains predominantly symptom based. Current clinical practice relies heavily on subjective patient-reported outcomes, which are influenced by psychological, cultural, and individual factors. Standardization of symptom assessment across studies also remains challenging because different questionnaires measure different symptom domains.[43] Emerging technologies, including wearable physiological sensors, artificial intelligence-based predictive algorithms, eye-tracking systems, and multimodal biomarker integration, offer promising opportunities for developing objective diagnostic tools. Future diagnostic approaches are expected to combine clinical history with continuous physiological monitoring to identify susceptible individuals before symptom onset and enable personalized preventive interventions.

Table 3. Common Clinical Manifestations of Motion Sickness

Table 4. Diagnostic Tools Used in Motion Sickness Assessment

5. Pharmacological Management

The mainstay of motion sickness prevention and treatment is still pharmacological therapy, especially for people who are subjected to lengthy or inevitable motion. The vestibular system, brainstem emetic centres, and autonomic pathways that cause nausea and vomiting are the main targets of current treatments. Antimuscarinic medications and first-generation antihistamines remain first-line pharmacological treatments since motion sickness is primarily mediated by cholinergic and histaminergic neurotransmission [44]. Neurokinin-1 (NK1) receptor antagonists and innovative drug delivery methods have been developed more recently in neuropharmacology with the goal of increasing efficacy while reducing side effects.

The expected period of motion exposure, the intensity of symptoms, the patient's age, comorbid conditions, occupational requirements, and the desire to reduce drowsiness or cognitive impairment are all important considerations when choosing a pharmaceutical treatment.

5.1 Antimuscarinic Agents

Scopolamine

The most popular medication for preventing motion sickness is scopolamine (also known as hyoscine), which continues to be the benchmark by which more recent treatments are evaluated. As a non-selective muscarinic receptor antagonist, scopolamine suppresses vestibular signals and lessens activation of the emetic reflex by blocking cholinergic neurotransmission in the vomiting center and vestibular nuclei.[45]

The most popular method of administering scopolamine is as a transdermal patch applied behind the ear four to six hours prior to travel. Because the patch releases the medication continuously for up to 72 hours, it is especially appropriate for extended sea travel, cruises, flying, and space travel. Although transdermal administration is still the recommended method because to prolonged plasma concentrations and enhanced patient compliance, oral, buccal, intranasal, and injectable formulations have also been studied..^[46]

Scopolamine dramatically lowers the frequency and intensity of motion sickness-related nausea, vomiting, dizziness, and autonomic symptoms, according to numerous randomized clinical trials. However, anticholinergic side effects, including as dry mouth, impaired vision, sleepiness, mydriasis, urine retention, and occasionally disorientation, especially in older people, restrict its therapeutic use. Therefore, patients with narrow-angle glaucoma, urinary outflow blockage, or cognitive impairment should utilize scopolamine with caution.

5.2 Histamine H1-Receptor Antagonists

Because they inhibit H1 receptors in vestibular pathways and have additional anticholinergic effect, first-generation antihistamines continue to be among the most often prescribed drugs for motion sickness.[47]

Typical agents are as follows:

Dimenhydrate Meclizine

Cyclizine

Promethazine

Cinnarizine

These medications are especially useful for short-distance travel and are often given 30 to 60 minutes before departure. In many nations, dimenhydrinate and meclizine are commonly accessible over-the-counter drugs that effectively prevent mild-to-moderate motion sickness.[48]

Although promethazine is one of the most effective antihistamines for severe motion sickness, it typically has anticholinergic side effects, drowsiness, and reduced psychomotor function. Although cinnarizine has been shown to help with vestibular problems and has both antihistaminic and calcium channel-blocking qualities, long-term usage may seldom cause extrapyramidal symptoms.

Antihistamines are still quite effective, but their sedative qualities prevent them from being used by pilots, professional drivers, members of the armed forces, and those in jobs where safety is crucial.^[49]

5.3 Neurokinin-1 (NK1) Receptor Antagonists

As our understanding of the role of Substance P and neurokinin-1 receptors in central emetic pathways has grown, NK1 receptor antagonists for motion sickness have been produced ^[50].

At the moment, tradipitant is the agent in this class that has been studied the most. Tradipitant prevents substance P-mediated activation of vomiting pathways without impairing vestibular function by specifically inhibiting NK1 receptors located in the area postrema and nucleus tractus solitarius.^[51]

According to clinical research, tradipitant exhibits favorable tolerability when compared to traditional anticholinergic drugs and considerably lowers the frequency of vomiting during maritime travel. NK1 receptor antagonists are promising substitutes for people who need to maintain cognitive function because they cause less drowsiness than scopolamine and first-generation antihistamines. However, more thorough randomized trials are required before these medicines can be employed in routine clinical practice.^[52]

5.4 Dopamine and Serotonin Receptor Antagonists

Even though serotonin (5-HT3) and dopamine D2 receptor antagonists are highly effective antiemetics in chemotherapy-induced and postoperative nausea, their role in motion sickness is comparatively limited.^[53]

Agents such as metoclopramide, domperidone, ondansetron, and granisetron primarily act by suppressing emetic pathways outside the vestibular system and therefore demonstrate relatively poor efficacy against vestibular-mediated nausea. Consequently, these medications are generally reserved for managing persistent vomiting rather than preventing motion sickness itself.

5.5 Emerging Drug Delivery Systems

One of the major limitations of conventional oral therapy is delayed gastrointestinal absorption during motion sickness because gastric emptying is frequently impaired. This has encouraged the development of alternative drug delivery systems capable of providing rapid systemic absorption while avoiding first-pass metabolism.^[54]

Transdermal Delivery

Transdermal scopolamine remains the most successful sustained-release formulation currently available. Continuous drug delivery over 72 hours improves therapeutic efficacy, enhances patient adherence, and minimizes fluctuations in plasma drug concentrations^[30].

Buccal Drug Delivery

Buccal films and rapidly dissolving oral formulations have emerged as attractive alternatives because they bypass hepatic first-pass metabolism and permit rapid drug absorption through the highly vascular oral mucosa. These formulations are particularly advantageous for patients experiencing nausea or vomiting, where swallowing conventional tablets may be difficult.

Intranasal Delivery

Intranasal administration provides rapid absorption through the nasal mucosa and offers potential direct nose-to-brain drug transport. Experimental studies evaluating intranasal scopolamine have demonstrated rapid onset of action and promising efficacy in space motion sickness, although optimization of dosing strategies and long-term safety requires further investigation.^[55]

Nanotechnology-Based Delivery

Nanoparticle-mediated drug delivery systems such as lipid nanoparticles, nanoemulsions, andpolymeric nanocarriers, are increasingly being investigated for targeted central nervous system drug delivery. These platforms may enhance drug bioavailability, improve brain penetration, reduce systemic adverse effects, and facilitate personalized therapeutic strategies.^[56]

5.6 Personalized Pharmacotherapy

Growing recognition of substantial interindividual variability in motion sickness susceptibility has shifted research toward precision medicine approaches. Genetic polymorphisms affecting vestibular signaling, autonomic regulation, neurotransmitter function, and drug metabolism may influence both disease susceptibility and therapeutic response.

Future pharmacological management is expected to incorporate genetic profiling, physiological biomarkers, wearable sensor technology, and artificial intelligence-based predictive algorithms to guide individualized drug selection, optimize dosing, and minimize adverse effects.^[57]

Table 5. Pharmacological Agents Used in Motion Sickness

Table 6. Emerging Drug Delivery Systems for Motion Sickness

Critical Perspective

Despite decades of clinical use, current pharmacological therapies remain largely preventive rather than curative, and their effectiveness is frequently limited by sedation and anticholinergic adverse effects ^[58]. Emerging therapies such as NK1 receptor antagonists, intranasal formulations, and nanotechnology-based delivery systems represent important advances, but robust multicentre clinical Trials are still required to determine their cost-effectiveness, comparative efficacy, and long-term safety. Future therapeutic strategies will likely move toward precision pharmacotherapy, integrating biomarkers, genetic profiling, and real-time physiological monitoring to tailor treatment according to an individual's susceptibility and exposure profile.^[59]

6. Non-pharmacological Management

Non-pharmacological interventions constitute an essential component of motion sickness management, particularly for individuals who cannot tolerate pharmacological therapy, require prolonged or repeated exposure to motion, or perform occupations where medication-induced sedation is unacceptable. These strategies primarily aim to minimize sensory conflict, facilitate vestibular adaptation, improve autonomic regulation, and reduce symptom severity without producing systemic adverse effects. Although the effectiveness of individual interventions varies, combining behavioural, environmental, vestibular, and technological approaches often provides greater symptom control than any single strategy alone.^[60]

6.1 Behavioral and Environmental Modifications

Behavioral modification remains the first-line preventive strategy for individuals with mild or intermittent motion sickness. Because motion sickness results from incongruent sensory inputs, interventions that improve agreement between visual and vestibular information can substantially reduce symptom development.

Maintaining visual fixation on a stable external reference, particularly the horizon during sea travel or distant stationary objects during road travel, reduces visual–vestibular mismatch and improves spatial orientation. Conversely, activities requiring prolonged visual concentration on stationary objects, such as reading, smartphone use, or laptop operation during travel, increase sensory conflict and should be minimized whenever possible.^[61]

Seat selection also influences symptom severity. In automobiles, the front passenger seat experiences less angular and vertical acceleration than the rear seats. In aircraft, seats located near the wings correspond closely to the centre of gravity and therefore experience reduced motion. Similarly, midship cabins on large vessels generally exhibit lower oscillatory movement than cabins positioned at the bow or stern.

Environmental conditions contribute significantly to symptom severity. Adequate ventilation, cool ambient temperature, and avoidance of unpleasant odours reduce autonomic stimulation and improve passenger comfort^[62]. Individuals are also advised to avoid alcohol, nicotine, and heavy high-fat meals before travel because these factors delay gastric emptying and increase gastrointestinal discomfort.

6.2 Vestibular Adaptation and Habituation Training

Repeated controlled exposure to provocative motion results in progressive reduction of symptoms through central nervous system adaptation, a phenomenon known as habituation. Habituation represents among the most successful long-term protective mechanisms against motion sickness and forms the basis of vestibular rehabilitation programs used in aviation, maritime operations, military training, and spaceflight.

Vestibular adaptation exercises involve repeated head movements, gaze stabilization exercises, balance training, and controlled exposure to motion stimuli. These interventions enhance central sensory integration and improve vestibulo-ocular reflex adaptation, thereby reducing susceptibility during subsequent motion exposure.

Evidence suggests that structured vestibular rehabilitation is particularly beneficial in individuals with vestibular migraine, chronic dizziness, persistent postural-perceptual dizziness, and recurrent motion sickness. Nevertheless, exercise protocols remain heterogeneous across studies, highlighting the need for standardized rehabilitation guidelines.^[63]

6.3 Controlled Breathing and Relaxation Techniques

Controlled breathing techniques represent simple, inexpensive, and safe interventions capable of reducing motion sickness symptoms by modulating autonomic nervous system activity. Slow diaphragmatic breathing increases parasympathetic tone, decreases sympathetic activation, and reduces physiological responses associated with nausea, including tachycardia, sweating, and gastric dysrhythmia.

Relaxation strategies such as gradual muscular relaxation, guided visualization, and mindfulness meditation, have also demonstrated beneficial effects by reducing anxiety and improving autonomic stability. Because psychological stress increases susceptibility to motion sickness, these techniques may be particularly valuable for individuals experiencing anticipatory anxiety before travel.^[64]

Although current evidence is encouraging, further randomized controlled trials are necessary to determine the best breathing protocols and determine their long-term clinical effectiveness.

6.4 Dietary and Nutritional Interventions

Dietary modification has traditionally been recommended as an adjunctive strategy for preventing motion sickness. Consumption of light meals before travel is generally preferred, whereas heavy meals rich in fat delay gastric emptying and may exacerbate nausea.^[65]

Among nutritional interventions, Zingiber officinale, or ginger, has drawn the most interest from scientists. It is thought that bioactive substances like gingerols and shogaols have antiemetic effects by altering serotonergic signalling pathways and gastrointestinal motility. Due to variations in dosage, formulation, and research design, results from a number of clinical trials have shown only slight decreases in the intensity of nausea after taking ginger supplements.

Other commonly recommended remedies, including peppermint, lemon, citrus-flavoured candies, and adequate hydration, may improve subjective comfort; however, high-quality clinical evidence supporting their effectiveness remains limited. Consequently, these interventions should be regarded as supportive rather than definitive therapeutic strategies.^[66]

6.5 Acupressure and Complementary Therapies

Complementary therapies have gained increasing attention as potential non-pharmacological approaches to motion sickness management. Among these, Numerous studies have been conducted on the stimulation of the Pericardium-6 (P6 or Neiguan) acupressure point.

On the volar aspect of the P6 point, forearm, is traditionally associated with nausea control. Wristbands applying continuous pressure to this location have demonstrated variable effectiveness across clinical trials. While several studies report modest reductions in nausea and vomiting, systematic reviews conclude that the evidence's overall quality remains moderate because of methodological limitations and placebo effects.^[67]

Other complementary interventions—including acupuncture, aromatherapy, and biofeedback—have shown promising preliminary results but currently lack sufficient high-quality evidence for routine clinical recommendation.

6.6 Wearable Technologies and Digital Interventions

Rapid technological advances have resulted in the creation of wearable devices designed to reduce motion sickness through non-invasive neuromodulation. These devices typically stimulate branches of the vagus nerve or peripheral sensory nerves using mild electrical impulses, thereby modulating autonomic activity and reducing nausea.

Simultaneously, inventors of virtual reality software have developed adaptive display technologies that reduce cybersickness by enhancing head-tracking accuracy, optimizing frame rates, lowering visual latency, and restricting the field of view during rapid motion. There is also ongoing research on machine learning algorithms that can use physiological inputs from wearable biosensors to forecast the onset of symptoms.
These technologies mark a significant shift from symptom treatment to individualized prevention, despite the fact that they are still relatively young.

6.7 Integrated Multimodal Management

The utilization of multimodal management techniques as opposed to standalone therapies is becoming more and more supported by current research. where compared to any one intervention, the combination of behavioural modification, vestibular rehabilitation, regulated breathing, nutritional optimization, and pharmaceutical prophylaxis where appropriate seems to offer better symptom control.
For high-risk groups, such as astronauts, military personnel, commercial pilots, maritime workers, and people who frequently interact with virtual reality environments, this integrated approach is especially pertinent. As precision medicine develops, individualized treatment strategies based on each patient's vulnerability, job needs, and anticipated motion exposure are probably going to become the norm. [69]

Fig: 2  Non-pharmacological Management

Table 7. Non-pharmacological Interventions for Motion Sickness

Integrated Non-pharmacological Management of Motion Sickness

A publication-quality flowchart could illustrate:

Motion Exposure

↓
      Behavioural Strategies

Horizon fixation

Seat selection

Avoid reading/smartphones
↓
Vestibular Adaptation

Habituation

Gaze stabilization

Balance training
↓
Autonomic Regulation

Controlled breathing

Relaxation

Hydration
↓
Complementary Therapies

Ginger

P6 acupressure
↓
Emerging Technologies

Wearable neuromodulation

Adaptive VR systems

AI-guided prevention
↓
Reduced Motion Sickness Symptoms

Critical Perspective

The quality of the evidence supporting many non-pharmacological therapies is still inconsistent, despite the fact that they are typically safe, affordable, and appropriate for repeated use. The strongest clinical evidence supports behavioral changes and vestibular habituation, while alternative therapies like acupressure and ginger supplements show moderate but variable benefits. Adaptive virtual reality, wearable technology, and digital health platforms  have demonstrated a great deal of promise, but major multicentre clinical trials are needed to establish their long-term usefulness and cost-effectiveness. Standardized intervention procedures, objective physiological outcome assessments, and individualized multimodal treatment plans that combine pharmaceutical, technological, and behavioral techniques should be the main topics of future study.^[70]

7. Recent Advances in Motion Sickness Research and Therapeutic Strategies

Innovative preventive and therapeutic approaches have been sparked by recent developments in motion sickness research, which have significantly increased our understanding of its neurophysiological underpinnings. Conventional pharmaceuticals like scopolamine and first-generation antihistamines continue to be the mainstay of therapeutic care, but their widespread usage is constrained by side effects such drowsiness, dry mouth, impaired vision, and cognitive impairment.
As a result, modern research is now focused on creating wearable technology, digital health solutions, safer pharmaceutical agents, sophisticated drug delivery systems, and customized therapeutic approaches. In addition to improving symptom management, these innovations seek to improve patient safety, treatment compliance, and quality of life in a variety of contexts, including autonomous vehicles, virtual reality environments, traditional transportation, and spaceflight.

7.1 Intranasal Drug Delivery

Intranasal drug delivery has emerged as a promising alternative for the management of motion sickness because it allows rapid drug absorption through the highly vascularized nasal mucosa. In addition to providing quick systemic absorption, this route may enable direct drug transport to the central nervous system via the olfactory and trigeminal nerve pathways, potentially resulting in a faster therapeutic effect.

Several experimental intranasal formulations of scopolamine have shown encouraging outcomes in studies involving space motion sickness and simulated vestibular stimulation. These formulations produced a rapid onset of action and effectively reduced motion sickness symptoms. Despite these promising findings, further research is needed to improve formulation stability, ensure good local nasal tolerability, and establish standardized dosing before intranasal scopolamine can be widely adopted in clinical practice.^[75]

7.2 Neurokinin-1 Receptor Antagonists

Neurokinin-1 (NK1) receptor antagonists represent one of the most promising recent advances in the pharmacological management of motion sickness. These agents act by blocking the action of substance P, a neurotransmitter that plays a central role in activating the nucleus tractus solitarius and the area postrema, two important brainstem regions involved in the vomiting reflex. By inhibiting NK1 receptors, these drugs can prevent nausea and vomiting without directly affecting normal vestibular function.^[76]

Among the NK1 receptor antagonists under investigation, tradipitant has shown particularly encouraging results. In randomized clinical trials conducted during sea travel, tradipitant significantly reduced both the frequency and severity of vomiting compared with placebo, while causing minimal sedation. Unlike conventional antimuscarinic drugs such as scopolamine, tradipitant does not appear to impair cognitive performance. This characteristic makes it a potentially valuable option for individuals whose occupations require sustained alertness, including pilots, military personnel, astronauts, and others working in safety-sensitive environments.^[77]

Although the available evidence is encouraging, larger multicentre clinical trials are still needed to compare NK1 receptor antagonists directly with established therapies such as scopolamine. These studies will help determine their long-term efficacy, safety, and potential role in routine clinical management of motion sickness.

7.3 Vestibular Rehabilitation and Physiotherapy

Growing recognition of motion sickness as a disorder of multisensory integration has increased interest in vestibular rehabilitation as a valuable complementary treatment. Vestibular rehabilitation aims to improve the brain's ability to adapt to conflicting sensory inputs through a structured exercise program.

Modern rehabilitation programs typically include gaze stabilization exercises, vestibulo-ocular reflex (VOR) training, balance and postural control exercises, habituation techniques, and controlled breathing exercises. Together, these interventions promote central vestibular compensation and improve tolerance to motion-related stimuli.^[78]

Recent clinical studies have reported that structured vestibular rehabilitation can reduce the severity of motion sickness symptoms, improve postural stability, and enhance functional performance in individuals with recurrent motion sickness, vestibular migraine, and persistent dizziness. Furthermore, digital rehabilitation platforms and virtual reality-assisted balance training have expanded access to therapy by allowing personalized exercise programs and gradual progression based on individual needs. Despite these advances, rehabilitation protocols vary considerably across studies, highlighting the need for standardized clinical guidelines to ensure consistent treatment outcomes.^[79]

7.4 Wearable Technologies and Neuromodulation

Recent technological advances have led to the development of wearable devices designed to reduce motion sickness through non-invasive neuromodulation. These devices typically deliver low-intensity electrical stimulation to peripheral nerves, such as branches of the vagus or median nerve, to influence autonomic nervous system activity and alleviate nausea.

In addition to neuromodulation, wearable sensors capable of continuously monitoring physiological parameters—including heart rate variability, electrodermal activity, skin temperature, respiratory rate, and body movement—are increasingly being integrated with predictive algorithms. These systems can identify early physiological changes associated with the onset of motion sickness, enabling timely preventive interventions^.[80]

Although wearable technologies are still undergoing clinical validation, they represent an important shift from treating symptoms after they occur to preventing their development before they become clinically significant.

7.5 Artificial Intelligence and Predictive Analytics

Artificial intelligence (AI) has become one of the most rapidly evolving areas in motion sickness research. Machine learning models that integrate physiological biomarkers, eye-tracking data, head movement patterns, vestibular responses, and genetic information have shown promising potential for predicting an individual's susceptibility to motion sickness before symptoms appear.^[52]

AI-based predictive systems may have important applications in several fields, including:

• Autonomous vehicles
• Aviation
• Maritime transportation
• Military operations
• Space exploration
• Virtual and augmented reality

By identifying individuals at risk in real time, AI has the potential to enable adaptive changes in vehicle dynamics, virtual reality display settings, or personalized preventive medication. Such approaches may help prevent motion sickness rather than simply managing symptoms after they develop.^[81]

7.6 Cybersickness Mitigation Technologies

The rapid adoption of immersive virtual reality (VR) technologies has intensified research into strategies for reducing cybersickness, a form of visually induced motion sickness.[82] Current engineering approaches focus on minimizing the mismatch between visual and vestibular sensory inputs, which is considered a major cause of cybersickness.

Several technological improvements have been introduced to enhance user comfort during prolonged VR exposure, including reduced display latency, higher refresh rates, more accurate head tracking, dynamic field-of-view restriction, motion prediction algorithms, adaptive rendering techniques, and multisensory feedback systems. Together, these innovations help reduce sensory conflict and improve the overall virtual reality experience.

In addition, the integration of eye-tracking technology with adaptive software enables real-time optimization of display settings according to an individual's susceptibility to motion sickness, providing a more personalized and comfortable VR experience.

7.7 Nanotechnology and Targeted Brain Drug Delivery

Nanotechnology has emerged as one of the most promising areas for the future management of motion sickness. Nanomedicine-based drug delivery systems, including nanoemulsions, liposomes, polymeric nanoparticles, and lipid-based nanocarriers, have the potential to enhance drug transport from the nasal cavity directly to the brain while bypassing the blood–brain barrier. This targeted approach may improve therapeutic effectiveness and reduce the limitations associated with conventional drug delivery methods.^[83]

The use of nanocarrier systems offers several potential advantages, including improved drug solubility, enhanced bioavailability within the central nervous system, faster onset of therapeutic action, lower effective doses, reduced systemic toxicity, and sustained drug release. These features may contribute to better symptom control while minimizing adverse effects.

Although most nanotechnology-based therapies for motion sickness are still in the preclinical stage of development, they show considerable promise as next-generation strategies for the targeted and more effective treatment of motion sickness.

Table 8. Recent Advances in Motion Sickness Management

Current Limitations

• Sedation
• Cognitive impairment
• Poor patient compliance
• Delayed drug absorption

Recent Innovations

• Transdermal drug delivery systems
• Buccal films
• Intranasal drug delivery
• Neurokinin-1 (NK1) receptor antagonists
• Vestibular rehabilitation
• Wearable neuromodulation devices
• Artificial intelligence (AI)-based prediction models
• Adaptive virtual reality (VR) technologies
• Nanomedicine-based drug delivery

Future Outcomes

• Personalized treatment strategies
• Faster symptom relief
• Reduced adverse effects
• Precision-based prevention
• Improved quality of life

Critical Perspective

Recent advances have shifted the focus of motion sickness research from simply relieving symptoms to developing targeted, personalized, and technology-driven approaches for prevention and management.^[85] While transdermal scopolamine continues to be the preferred option for long-term prophylaxis, several emerging therapies—including NK1 receptor antagonists, intranasal drug delivery, wearable neuromodulation, and AI-based predictive systems—have shown considerable promise in improving treatment outcomes while minimizing adverse effects.

Despite these encouraging developments, most of these technologies are still in the investigational stage. Large, multicentre randomized clinical trials are needed to confirm their long-term efficacy, safety, and cost-effectiveness before they can be incorporated into routine clinical practice. Future progress will likely rely on close collaboration among neuroscientists, pharmacologists, biomedical engineers, and digital health experts to develop integrated and personalized strategies for preventing and managing motion sickness across both real-world and virtual environments.^[86]

8. Future Perspectives

Over the past few decades, the understanding of motion sickness has advanced considerably. What was once viewed mainly as a consequence of sensory conflict is now recognized as a complex neurophysiological disorder involving multisensory integration, autonomic regulation, genetic susceptibility, and higher cortical processing. Although substantial progress has been made in understanding its mechanisms and developing preventive therapies, important challenges remain, including accurately predicting individual susceptibility, improving treatment efficacy, minimizing adverse effects, and translating research findings into routine clinical practice^.[87]

8.1 Precision Medicine and Personalized Prevention

A major focus of future motion sickness research is the transition from generalized treatment approaches to personalized prevention strategies^.[87] Individuals differ considerably in their susceptibility to motion sickness, symptom severity, and response to therapy due to variations in genetic makeup, vestibular function, autonomic regulation, psychological factors, and environmental exposure.^[88]

Advances in genetic profiling, physiological biomarkers, and patient-specific clinical assessment may enable the early identification of individuals who are at greater risk of developing motion sickness before exposure to provocative motion. Such information could help clinicians select the most appropriate pharmacological or non-pharmacological intervention while reducing unnecessary drug exposure and minimizing adverse effects.^[89]

In addition, developments in pharmacogenomics may support individualized dosing strategies by identifying genetic variations that influence neurotransmitter activity, drug metabolism, and vestibular sensitivity, ultimately improving both treatment efficacy and safety.

8.2 Artificial Intelligence and Digital Health

Artificial intelligence (AI) is expected to play an increasingly important role in the diagnosis, prediction, and management of motion sickness. Machine learning models that integrate physiological signals, vestibular responses, eye-tracking data, and behavioural patterns have shown promising potential for predicting symptom onset before clinical symptoms become evident.

Future AI-driven systems may continuously analyse data collected from wearable devices, including heart rate variability, electrodermal activity, respiratory patterns, head movements, and eye movements, to estimate an individual's real-time risk of developing motion sickness. This information could support adaptive interventions such as modifying vehicle dynamics, optimizing virtual reality display settings, or recommending personalized prophylactic medication before symptoms occur.^[87]

AI may also improve passenger comfort in autonomous vehicles by intelligently controlling acceleration, braking, steering, and route planning to minimize motion patterns that commonly trigger motion sickness.

8.3 Next-Generation Drug Delivery Systems

Although transdermal scopolamine remains the current standard for prolonged motion sickness prophylaxis, pharmaceutical research is increasingly focused on developing targeted drug delivery systems that enhance therapeutic efficacy while reducing systemic side effects.

Emerging approaches—including intranasal nose-to-brain delivery, microneedle-assisted transdermal patches, buccal nanofilms, lipid nanoparticles, polymeric nanocarriers, and stimuli-responsive drug delivery systems—have demonstrated promising results in preclinical studies.^[88]

Among these, nanotechnology-based formulations are particularly attractive because they can improve drug delivery to the central nervous system by bypassing the blood–brain barrier. These systems may enhance drug bioavailability, prolong therapeutic action, enable lower therapeutic doses, and reduce systemic toxicity. As these technologies continue to advance, they have the potential to overcome many of the limitations associated with conventional oral and transdermal therapies, offering more effective and patient-friendly options for the future management of motion sickness.

8.4 Advances in Neuroscience and Biomarker Discovery

Rapid progress in neuroscience and neuroimaging is expected to deepen our understanding of the neural mechanisms underlying motion sickness. Advanced techniques such as functional magnetic resonance imaging (fMRI), electroencephalography (EEG), functional near-infrared spectroscopy (fNIRS), and comprehensive vestibular function tests are increasingly being used to investigate the neural networks involved in sensory conflict, autonomic responses, and symptom progression.^[88]

At the same time, researchers are exploring a range of physiological biomarkers, including heart rate variability, gastric myoelectrical activity, electrodermal responses, inflammatory mediators, and neurochemical markers, to improve the objective assessment of motion sickness.[88] The identification of reliable biomarkers could support early diagnosis, monitor treatment response, and help predict an individual's susceptibility. Such advances would be particularly valuable because the current diagnosis of motion sickness relies largely on subjective symptom reporting.

8.5 Emerging Therapeutic Targets

Ongoing advances in molecular neuroscience are opening new opportunities to develop therapies that extend beyond the conventional cholinergic and histaminergic pathways. Recent studies suggest that several biological pathways, including Substance P, neurokinin-1 (NK1) receptors, serotonergic and glutamatergic neurotransmission, endocannabinoid signalling, and neuroinflammatory processes, contribute to the development of motion sickness.[89]

Future pharmacological research is therefore likely to focus on highly selective receptor modulators that effectively control nausea while minimizing sedation and cognitive impairment. In addition, combination therapies targeting multiple neurotransmitter systems simultaneously may provide greater therapeutic benefit than the single-drug approaches currently used.

8.6 Human–Machine Interaction and Immersive Technologies

The rapid growth of virtual reality (VR), augmented reality (AR), mixed reality (MR), and autonomous transportation has introduced new challenges in the prevention and management of motion sickness. To address these challenges, researchers are developing engineering solutions that reduce sensory conflict through adaptive rendering, predictive eye-tracking, personalized display optimization, dynamic field-of-view adjustment, and multisensory feedback systems.^[90]

Similarly, future autonomous vehicles may incorporate real-time physiological monitoring to adjust acceleration, steering, suspension, and seating position according to each passenger's susceptibility to motion sickness. As immersive technologies become more common in healthcare, education, entertainment, military training, and transportation, the adoption of human-centred design principles will play an increasingly important role in improving user comfort and safety.^[95]

8.7 Standardization of Clinical Research

Despite decades of research, substantial variation still exists among clinical studies evaluating motion sickness interventions. Differences in symptom assessment tools, motion exposure methods, study populations, outcome measures, and definitions of treatment success make it difficult to compare findings across studies and draw consistent conclusions.

Future multicentre clinical trials should adopt standardized diagnostic criteria, validated assessment tools such as the Motion Sickness Assessment Questionnaire (MSAQ) and the Simulator Sickness Questionnaire (SSQ), and harmonized reporting guidelines to improve study quality, reproducibility, and the reliability of systematic reviews and meta-analyses.^[91] Greater collaboration among academic institutions, regulatory agencies, and industry partners will also be essential for translating research findings into clinical practice more efficiently.

8.8 Toward Precision Motion Sickness Management

The future of motion sickness management is expected to move beyond treating symptoms after they occur and toward predictive, preventive, personalized, and participatory healthcare. Advances in wearable biosensors, cloud-based health monitoring, artificial intelligence, digital therapeutics, pharmacogenomics, and targeted drug delivery systems may enable continuous monitoring of an individual's susceptibility and allow timely interventions before symptoms develop.^[92]

These precision medicine approaches have the potential to improve safety and performance in individuals at high risk of motion sickness, including astronauts, military personnel, commercial pilots, maritime workers, passengers in autonomous vehicles, and frequent users of virtual reality technologies.^[94]

Table 9. Future Research Priorities in Motion Sickness