Motion sickness or kinetosis is a condition in which a disagreement exists between visually perceived movement and the vestibular system’s sense of movement.
To understand motion sickness, it helps to understand a few parts of your body and how they affect the way you feel movement:
*inner ears – liquid in the semicircular canals of the inner ear allows you to sense if you’re moving, and, if you are, which way you’re moving – up, down, side to side, round and round, forward, or backward.
*eyes – what you see also lets your body know whether you’re moving and in which direction.
*skin receptors – these receptors tell your brain which parts of your body are touching the ground.
*muscles and joint sensory receptors – these sensing receptors tell your brain if you’re moving your muscles and which position your body is in.
The brain gets an instant report from these different parts of your body and tries to put together a total picture about what you are doing just at that moment. But if any of the pieces of this picture don’t match, you can get motion sickness.
For example, if you’re riding in a car and reading a book, your inner ears and skin receptors will detect that you are moving forward. However, your eyes are looking at a book that isn’t moving, and your muscle receptors are telling your brain that you’re sitting still. So the brain gets a little confused. Things may begin to feel a little scrambled inside your head at that point.
When this happens, you might feel really tired, dizzy, or sick to your stomach. Sometimes you might even throw up. And if you’re feeling scared or anxious, your motion sickness might get even worse.
Depending on the cause it can also be referred to as seasickness, carsickness, simulation sickness, airsickness, or space sickness.
Kinds of Motion Sickness:
Airsickness is a sensation which is induced by air travel. It is a specific form of motion sickness, and is considered a normal response in healthy individuals. Airsickness occurs when the central nervous system receives conflicting messages from the body (including the inner ear, eyes and muscles) affecting balance and equilibrium.
Seasickness is a form of motion sickness characterized by a feeling of nausea and, in extreme cases, vertigo experienced after spending time on a craft on water. It is typically brought on by the rocking motion of the craft.
Simulation sickness, or simulator sickness, is a condition where a person exhibits symptoms similar to motion sickness caused by playing computer/simulation/video games.
The most common theory for the cause of simulation sickness is that the illusion of motion created by the virtual world, combined with the absence of motion detected by the inner ear, causes the area postrema in the brain to infer that one is hallucinating and further conclude that the hallucination is due to poison ingestion. The brain responds by inducing nausea and mass vomiting, to clear the supposed toxin. According to this theory, simulation sickness is just another form of motion sickness.
The symptoms are often described as quite similar to that of motion sickness. Some can range from headache, drowsiness, nausea, dizziness, vomiting and sweating. A research done at the University of Minnesota had students play Halo for less than an hour, and found that up to 50 percent felt sick afterwards.
In a study conducted by U.S. Army Research Institute for the Behavioral and Social Sciences in a report published May 1995 titled “Technical Report 1027 – Simulator Sickness in Virtual Environments”, out of 742 pilot exposures from 11 military flight simulators, “approximately half of the pilots (334) reported post-effects of some kind: 250 (34%) reported that symptoms dissipated in less than 1 hour, 44 (6%) reported that symptoms lasted longer than 4 hours, and 28 (4%) reported that symptoms lasted longer than 6 hours. There were also 4 (1%) reported cases of spontaneously occurring flashbacks”.
Space sickness was effectively unknown during the earliest spaceflights, as these were undertaken in very cramped conditions; it seems to be aggravated by being able to freely move around, and so is more common in larger spacecraft. Around 60% of all Space Shuttle astronauts currently experience it on their first flight; the first case is now suspected to be Gherman Titov, in August, 1961 onboard Vostok 2, who reported dizziness and nausea. However, the first significant cases were in early Apollo flights; Frank Borman on Apollo 8 and Rusty Schweickart on Apollo 9. Both experienced identifiable and reasonably severe symptoms â€” in the latter case causing the mission plan to be modified.
Signs and Symptoms:
The most common signs and symptoms of motion sickness include:
*Paleness of the skin
Dizziness, fatigue, and nausea are the most common symptoms of motion sickness. Sopite syndrome is also a side effect of motion sickness. In fact, nausea in Greek means seasickness (naus means ship). If the motion causing nausea is not resolved, the sufferer will frequently vomit. Unlike ordinary sickness, vomiting in motion sickness tends not to relieve the nausea.
Motion sickness occurs when the body, the inner ear, and the eyes send conflicting signals to the brain. This reaction is generally provoked by a moving vehicle such as a car, boat, airplane, or space shuttle, but it may also happen on flight simulators or amusement park rides. From inside a ship’s cabin, the inner ear may sense rolling motions that the eyes cannot perceive, and, conversely, the eyes may perceive movement on a “virtual reality” simulation ride that the body does not feel. Interestingly, once a person adapts to the movement and the motion stops, the symptoms may recur and cause the person to adjust all over again (although, this reaction is generally brief). In addition, even anticipating movement can cause anxiety and symptoms of motion sickness. For example, a person with a previous experience of motion sickness may become nauseous on an airplane before take-off.
About 33% of people are susceptible to motion sickness even in mild circumstances such as being on a boat in calm water, although nearly 66% of people are susceptible in more severe conditions. Approximately 50% of the astronauts in the U.S. space program have suffered from space sickness.Individuals and animals without a functional vestibular system are immune to motion sickness.
Motion sickness on the sea can result from being in the berth of a rolling boat without being able to see the horizon. Sudden jerky movements tend to be worse for provoking motion sickness than slower smooth ones, because they disrupt the fluid balance more. A “corkscrewing” boat will upset more people than one that is gliding smoothly across the oncoming waves. Cars driving rapidly around winding roads or up and down a series of hills will upset more people than cars that are moving over smooth, straight roads. Looking down into one’s lap to consult a map or attempting to read a book while a passenger in a car may also bring on motion sickness.
The most common hypothesis for the cause of motion sickness is that it functions as a defense mechanism against neurotoxins. The area postrema in the brain is responsible for inducing vomiting when poisons are detected, and for resolving conflicts between vision and balance. When feeling motion but not seeing it (for example, in a ship with no windows), the inner ear transmits to the brain that it senses motion, but the eyes tell the brain that everything is still. As a result of the disconcordance, the brain will come to the conclusion that one of them is hallucinating and further conclude that the hallucination is due to poison ingestion. The brain responds by inducing vomiting, to clear the supposed toxin.
The following are the most common risk factors for motion sickness:
- Riding in a car, boat, airplane, or space shuttle
- Age — children between the ages of 2 – 12 are most at risk. Occurrence of motion sickness declines with age (this is probably due to behavioral changes and coping strategies rather than anything inherent in the aging process).
- Susceptibility to nausea or vomiting
- Heightened level of fear or anxiety
- Exposure to unpleasant odors
- Poor ventilation
- Spending long hours at a computer screen
- Being outside of the earth’s gravitational force
Most people who have experienced motion sickness in the past ask their health care provider how to prevent another episode from occurring in the future. Rarely will an individual arrive at his or her health care provider’s office actually experiencing motion sickness. To establish a diagnosis of motion sickness, the provider will inquire about the individual’s symptoms as well as the event that typically causes the condition (such as riding in a boat, flying in a plane, or driving in car). Laboratory tests are generally not necessary to establish a diagnosis of motion sickness.
The following general measures may be taken to help avoid the discomfort caused by motion sickness:
- Reduce anxiety and fears, particularly through methods such as cognitive-behavioral therapy and biofeedback.
- Use head rests to minimize head movements.
- Maintain proper ventilation to decrease foul odors that may cause nausea.
- Stay occupied to distract the mind from thinking about motion sickness. Reading may worsen symptoms.
- Particular exercises, such as tumbling or jumping on a trampoline, may desensitize an individual prior to being in a situation that causes motion sickness.
Individuals who commonly experience motion sickness on a plane should take the following preventive measures:
- Avoid bulky, greasy meals and overindulgence in alcoholic beverages the night before air travel.
- Eat light meals or snacks that are low in calories in the 24 hours before air travel.
- Avoid salty foods and dairy products before air travel.
- Sit toward the front of the aircraft or in a seat by the wing because the ride will feel smoother in these locations.
- Eat foods high in carbohydrates before air travel.
Individuals with a tendency toward motion sickness on a boat should take the following preventive measures:
- Passengers below the deck should keep their eyes closed and minds occupied (by engaging in conversation, for example).
- Passengers on the deck should keep their eyes fixed on the horizon or visible land.
While medications may be an acceptable treatment for travelers who occasionally experience motion sickness, the goal for individuals who experience motion sickness on a regular basis or whose work is affected by their symptoms is to learn to control — and eventually prevent — these symptoms. This may be accomplished with mind-body practices, such as cognitive-behavioral therapy and biofeedback. Other alternatives to medication include homeopathy, acupuncture, dietary supplements, dietary changes, and physical exercise.
Medications for motion sickness may cause drowsiness and impair judgement and, therefore, should be avoided in pilots, astronauts, ship crew members, and individuals in any other occupation where heavy equipment is operated or where being alert is critical. The following medications are a reasonable option for infrequent travelers and others who experience motion sickness occasionally:
- Scopolamine — most commonly prescribed medication for motion sickness. It must be taken before the onset of symptoms. It is available in patch form that is placed behind the ear 6 – 8 hours before travel. The effects last up to 3 days. Side effects may include dry mouth, drowsiness, blurred vision, and disorientation.
- Promethazine — take 2 hours before travel. The effects last between 6 – 8 hours. Side effects may include drowsiness and dry mouth.
- Cyclizine — most effective when taken at least 30 minutes before travel. It is not recommended for children younger than 6, and side effects are similar to scopolamine.
- Dimenhydrinate — take every 4 – 8 hours. Side effects are similar to scopolamine.
- Meclizine — most effective when taken 1 hour before travel. It is not recommended for children under 12, and side effects may include drowsiness and dry mouth
Nutrition and Dietary Supplements:
Generally, small frequent meals are recommended for individuals prone to motion sickness. A comprehensive treatment plan for recovering from motion sickness may include a range of complementary and alternative therapies. Ask your team of health care providers about the best ways to incorporate these therapies into your overall treatment plan. Always tell your health care provider about the herbs and supplements you are using or considering using.
Following these nutritional tips may help reduce symptoms and improve overall health:
- Try to eliminate potential food allergens, including dairy, wheat (gluten), corn, preservatives, and food additives. Your health care provider may want to test for food sensitivities.
- Eat antioxidant foods, including fruits (such as blueberries, cherries, and tomatoes) and vegetables (such as squash and bell peppers).
- Eat foods high in B-vitamins and calcium, such as almonds, beans, whole grains (if no allergy), dark leafy greens (such as spinach and kale), and sea vegetables.
- Avoid refined foods, such as white breads, pastas, and especially sugar.
- Eat fewer red meats and more lean meats, cold-water fish, tofu (soy, if no allergy), or beans for protein.
- Use healthy oils in foods, such as olive oil or vegetable oil.
- Reduce or eliminate trans-fatty acids, found in commercially baked goods such as cookies, crackers, cakes, French fries, onion rings, donuts, processed foods, and margarine.
- Avoid coffee and other stimulants, alcohol, and tobacco.
- Drink 6 – 8 glasses of filtered water daily.
Nutritional deficiencies may be addressed with the following supplements:
- A multivitamin daily, containing the antioxidant vitamins A, C, E, the B-complex vitamins, and trace minerals such as magnesium, calcium, zinc, and selenium.
- Omega-3 fatty acids, such as fish oil, 1 – 2 capsules or 1 tablespoonful oil one to three times daily, to help decrease inflammation and help with immunity. Cold-water fish, such as salmon or halibut, are good sources.
- Probiotic supplement (containing Lactobacillus acidophilus among other species), 5 – 10 billion CFUs (colony forming units) a day, when needed for maintenance of gastrointestinal and immune health. You should refrigerate your probiotic supplements for best results.
- Alpha-lipoic acid, 25 – 50 mg twice daily, for antioxidant support.
- Resveratrol (from red wine), 50 – 200 mg daily, to help decrease inflammation and for antioxidant effects.
- 5-hydroxytryptophan (5-HTP), 50 mg two to three times daily, for mood stabilization.
- Grape seed extract ( Vitis vinifera ) standardized extract, 25 – 100 mg three times daily, for antioxidant effects.
Herbs are generally a safe way to strengthen and tone the body’s systems. As with any therapy, you should work with your health care provider to get your problem diagnosed before starting any treatment. You may use herbs as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, you should make teas with 1 tsp. herb per cup of hot water. Steep covered 5 – 10 minutes for leaf or flowers, and 10 – 20 minutes for roots. Drink 2 – 4 cups per day. You may use tinctures alone or in combination as noted.
- Ginger ( Zingiber officinale ) standardized extract, 250 mg three times daily as needed, for symptoms of nausea.
- Peppermint ( Mentha piperita ) standardized extract, 1 enteric coated tablet two to three times daily as needed. You may also make a tea of the leaf.
- Milk thistle ( Silybum marianum ) seed standardized extract, 80 – 160 mg two to three times daily, for detoxification support.
Although results have been less convincing, studies suggest that acupressure may help reduce symptoms of motion sickness in the same way as acupuncture. An acupressure practitioner works with the same points used in acupuncture, but stimulates these healing sites with finger pressure, rather than inserting fine needles.
The acupuncture point known as Pericardium 6, located on the palm side of the wrist about the length of 2 fingernails up the arm from the center of the wrist crease, is a classic point for motion sickness and nausea of all kinds. Many travel stores sell wrist bands with built in buttons designed to apply acupressure to this point.
Massage and Physical Therapy:
One case study of a woman with motion sickness suggests that balance training and habituation (reducing or modifying one’s response to a stimulus that causes motion sickness) may help diminish the symptoms of the condition. The use of habituation for the treatment of motion sickness is based on the theory that when an individual prone to motion sickness is repetitively exposed to the stimulus that causes motion sickness (such as driving in a car or riding on an elevator) in a controlled, supervised fashion, they will become used to (habituate) that stimulus. Over time, the stimulus will no longer evoke the motion sickness response, and symptoms will diminish.
Cranio-Sacral therapy may be helpful in treating acute motion sickness and diminishing oneâ€™s tendency towards motion sickness. Ask your health care provider about more information on this alternative treatment for motion sickness.
Few studies have examined the effectiveness of specific homeopathic remedies. A professional homeopath, however, may recommend one or more of the following treatments for motion sickness based on their knowledge and clinical experience. Before prescribing a remedy, homeopaths take into account a personâ€™s constitutional type — your physical, emotional, and intellectual makeup. An experienced homeopath assesses all of these factors when determining the most appropriate remedy for a particular individual.
- Borax — for nausea caused by downward motions, such as landing in an airplane
- Cocculus — the primary treatment for motion sickness, particularly if nausea and vertigo or other type of dizziness are present
- Nux vomica — for motion sickness accompanied by headache, nausea, and ringing in the ears
- Petroleum — for dizziness and nausea that occur when riding in a car or boat
- Sepia — for motion sickness brought on by reading while in a moving vehicle
- Tabacum — for motion sickness with severe nausea and vomiting
Biofeedback Training and Relaxation
In a study of 55 pilots who had to stop flying due to symptoms of motion sickness, 76% of them successfully overcame their motion sickness and were able to return to work after participating in a biofeedback training and relaxation program. Biofeedback instruments recorded skin temperature and changes in muscle tension while the pilots were exposed to a stimulus that caused motion sickness (sitting in a tilting, rotating chair). While in the chair, the pilots performed various relaxation techniques, such as deep muscle relaxation and mental imagery. Over time, the pilots became used to the rotating chair, and they no longer felt sick because they learned to relax.
Cognitive Behavioral Therapy
The goal of cognitive behavioral therapy is to alleviate the anxiety that some people experience simply thinking about movement or motion sickness. In a study of 50 pilots who occasionally experienced motion sickness, 86% of them successfully overcame their symptoms after cognitive behavioral therapy. During this therapy, individuals are exposed to a provocative stimulus (such as a tilting, rotating chair) in a slow and controlled fashion until they experience some symptoms of motion sickness, but not until the symptoms become overwhelming. As the individual performs better and better on the rotating chair, they build confidence, reducing their anxiety.
In a study of 46 people with motion sickness, those who were instructed to take slow, deep breaths had a significant reduction in symptoms of motion sickness compared to those who breathed normally or counted their breaths. Interestingly, involuntary rapid and shallow breathing often exacerbates symptoms of motion sickness. While it makes sense that slow, deliberate breathing would help reduce the anxiety associated with motion sickness, further studies are needed to determine whether breathing techniques effectively diminish the symptoms associated with the condition.
Prognosis and Complications:
While motion sickness has no long-term complications, the condition may be devastating for those in an occupation that involves constant movement, such as a flight attendant, pilot, astronaut, or ship crew member.
The symptoms of motion sickness generally disappear quickly once the journey is over. People who travel infrequently may also become accustomed to movement during a trip lasting several days. Even those who travel often may improve from repeated exposures to the same type of experience. However, people who become anxious before a journey often experience worsened symptoms of motion sickness and tend to require more formal interventions, such as biofeedback and relaxation training
Click to learn more:->How to stop travel sickness :
Disclaimer: This information is not meant to be a substitute for professional medical advise or help. It is always best to consult with a Physician about serious health concerns. This information is in no way intended to diagnose or prescribe remedies.This is purely for educational purpose.
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