Motion sickness is a disorder related to movement. Described as malaise accompanied by nausea and sometimes vomiting, it is a multifactorial neurodegenerative crisis involving the inner ear. Although its mechanisms remain poorly understood, motion sickness does not constitute a reason for medical consultation but is, more often than not, the subject of requests for advice from the pharmacy.
What is motion sickness ?
Motion sickness is defined by a set of symptoms caused by the perception of real or apparent movements. Apart from individuals with a non-functioning vestibular system, anyone can be sickened by an appropriate stimulus that is sufficiently long and intense. Four symptoms appear with great regularity: facial pallor, cold sweats, nausea and vomiting unrelated to gastric contents, and all the more painful when the stomach is empty.
How to explain it ?
Motion sickness is generally associated with the movement of physical or virtual vehicles. Under sensory conflict theory, motion sickness occurs when sensory inputs differ from those predicted by an internal model. The time constant of the vestibular responses is a marker of individual susceptibility to motion sickness. Individuals with a non-functioning vestibular system are immune to motion sickness.
The triggering of motion sickness from purely visual stimulation is a well-known phenomenon whose practical importance has increased with the development of driving simulators and, above all, of virtual reality systems.
However, even for purely visual stimulation, the presence of a functional vestibular system is essential for the onset of motion sickness. Thus, a usually nauseating optokinetic stimulation in healthy subjects is totally ineffective in subjects without vestibular function.
Vomiting results from a co-contraction of the inspiratory and expiratory muscles. Triggered by the excitement of a rather poorly limited area in the midbrain, this area corresponds to the “center of vomiting”. This center, formerly seen as an anatomic-functional unit in the dorsolateral part of the bulbar reticular formation, is now considered more as a functional or pharmacological entity in which different central groups participate. In addition to afferents from the digestive tract, the “vomiting center” can be activated by afferents in the pharyngeal, vestibular, cardiac, peritoneal, and higher nervous system centers such as the thalamus, hypothalamus and cerebral cortex. In turn, it causes vagal arousal which triggers the vomiting reflex.
Motion sickness from a historical perspective :
The earliest writings relating to motion sickness date back to ancient Greece. The term “nausea” is derived from the Greek word naus, which means vessel.
The most common remedy from the Middle Ages was wine, believed to provide resistance to seasickness. In a text which was apparently written for the Duke of Normandy, the monks of Salerno advocated drinking it mixed, but without specifying with what. The successive editors of this text (200 editions) each brought their own interpretation, but many were
I agree that you had to mix the wine with seawater.
Motion sickness has not always been considered a plague; until the beginning of the 19th century, it was believed to have healing properties.
Patients suffering from various ailments were sent on cruises for the sole purpose of being ill, vomiting being supposed to relieve these ailments.
A turning point was taken in the history of the etiology of motion sickness when, in 1881, Irwin and De Champeaux observed similarities between the symptoms of motion sickness and those of the disease.
de Ménière and when, in 1882, James found that the deaf-mute from birth were insensitive to motion sickness. This observation thus gave rise to vestibular theories of motion sickness, theories still relevant today in the deeply reworked form of “sensory conflict”
Some naturopathic tips to prevent motion sickness :
- Avoid large meals before travel, but do not leave on an empty stomach. Choose solid food rather than liquid
- Give up alcohol, tobacco and coffee, before and during the trip
- Keep your head straight, without making sudden movements during the trip
- In the car, sit in the front next to the driver, or in the rear in the middle, and look far ahead
- On the train or on the boat, sit facing the direction of travel. Some people feel bad when they are seated in the opposite direction
- In an airplane or in a boat, choose a seat located in the center of the device: the movements are of lower amplitude
- Pick a seat by the window and watch the scenery in the distance. As long as the eyes perceive the displacement, the disease manifests itself less quickly
- When on a boat, avoid staying indoors, confined spaces favor the onset of symptoms
- If you are prone to motion sickness, refrain from reading, writing, or engaging in any activity that requires your visual attention
- Controlled breathing is half the effectiveness of treatment with scopolamine without having any side effects. It is enough to have an abdominal breathing as regular as possible without increasing the amplitude
- Regular practice of an activity such as boating leads to a decrease in the occurrence of motion sickness. This is by far the most effective way to prevent them
Food side :
Dietary recommendations, such as eating a reasonable (not too much, not too little), alcohol-free meal before a nauseous situation seem sound. Nevertheless, a study suggests that a meal high in protein may prevent motion sickness.
Which medicinal plants to turn to in case of motion sickness ?
Lemon essential oil :
Taking a drop of lemon essential oil on a neutral tablet before leaving on a trip greatly reduces the inconvenience caused by motion sickness.
Peppermint leaves :
Chewing a few peppermint leaves during transport helps to significantly relieve the feeling of nausea.
Ginger root :
The ginger rhizome is used in the prevention and treatment of nausea due to motion sickness and seasickness. Several studies have shown its effectiveness in this situation.
Cocculin (homeopathic complex) :
This homeopathic medicine is a complex of several effective strains to fight against nausea and / or vomiting due to motion sickness.Sources :
- Reason JT, Brand JJ. Motion sickness. Londres: Academic Press, 1975:182-4
- Irwin JA. The literature of sea-sickness. Med Rec 1893:617-9
- Claremont CA. The psychology of sea-sickness. Psyche 1931;11:86-90