Fish in space The motion sickness on the trail

Fish in space should explain motion sickness

19.04.2013

Every year during the holiday season, it is again present: the motion sickness - tormenting many holidaymakers who have to fight while driving, on the ship, in the bus or plane among other things with nausea and vomiting. In many cases, fatigue, headaches, difficulty concentrating or mood swings occur, until then the actual motion sickness in addition to the nausea manifests itself through symptoms such as paleness, fatigue, palpitations, low blood pressure or dizziness. German scientists are now sending fish and snails into space to better explore the barely researched motion sickness.

Fish get sick as people do
The causes of the so-called „travel sickness“ (or even motion sickness, technical kinetosis) are still not fully understood - so researchers from the universities of Erlangen-Nuremberg and Hohenheim start this Friday a very special experiment: So the scientists want to send fish and snails into space, as these as well „car sick“ can be like humans. The extraordinary crew of the Soyuz rocket is to be supplemented by various algae to possibly get information about cell changes in the state of weightlessness, why astronauts are so heavily involved in the use of the material.

Causes of motion sickness have not yet been clarified
Even if there is still a need for research into the cause of motion sickness, researchers currently assume that "the symptoms are triggered by unfamiliar accelerations (for example, in waves on ships) that act on the balance organ in the inner ear via various stimuli". If these movements are not followed all the time by the eyes, the brain can no longer assign them and records them as an error message, which finally triggers the familiar symptoms of motion sickness, such as nausea or dizziness. This applies according to Peter Richter from the University of Erlangen for both humans and for fish, because „just the inner ear of the fish is very similar to the human ear.“

Weightlessness prevents balance by the brain
According to Richter, it has already been found in earlier investigations that it was the fishes that showed particularly strong symptoms, whose ear buds had different sizes in the ears. This is usually not a problem, because if humans or fish are in familiar surroundings, this difference would be compensated by the brain. However, leaving the familiar environment, this mechanism no longer works - just like in space, because then, according to Richter's explanation, the fish would try to correct the alleged misunderstanding by reflexes - just like people who try in case of dizziness, to avoid a fall by countermovements.

Closed ecosystem for four weeks into space
For their new experiment, the scientists have now set four weeks in which, among other things, they want to gain insights into how weightlessness affects the formation of auditory stones and the bones and muscles of fish. For this purpose, a self-contained ecosystem will be sent into space for the first time - with 40 cichlid larvae, post-horn snails, the algae species Euglena gracilis and the water plant Hornkraut.

Algae should also provide new insights
In addition to the fish, the algae are in the focus of observation, because according to Richter has been known for some time, „that after just a few seconds in weightlessness both the reading of the genes in the cell nucleus and the proteins in the cells change.“ Therefore, the next step is to investigate the underlying mechanisms“, so the expert, because these processes would have strong similarities to the physical reactions of astronauts: „As soon as humans are in space for a longer time, the immune system is weakened relatively quickly, the bones become weak, similar to osteoporosis, and muscle atrophy occurs.“

Unusual crew starts on Friday
Next Friday, the journey for the extraordinary crew of the Soyuz rocket from the Kazakh spaceport Baikonur will start - in preparation, the scientists had to accommodate fish, algae and all the technology in a box the size of a beer crate and protect against harmful influences such as space radiation , The fully automatic implementation of the experiment is obvious: If the aquarium unexpectedly lose water, according to project leader Michael Lebert, this would be very difficult to collect in weightlessness - and there is a risk that the on-board electronics on board would be severely damaged could be.

Nausea and vomiting as an essential survival reaction
In addition to the topic „travel sickness“ Researchers are also concerned with vomiting as a result of excessive alcohol consumption - because, according to scientists, the mechanism behind both phenomena could be the same. Thus it could be assumed that, historically, nausea and vomiting would be a survival-necessary reaction, since people used to get poisonous foods when trying out unknown plants. Therefore, vomiting according to project staff Ferdinand Haag "for all orally ingested poisons a very helpful reflex" - which would probably act in motion sickness in the same way - only that here not just the poisoning, but unfamiliar movements of the triggers would be.

Women more frequently affected by motion sickness than men
Even if, in principle, anyone with a healthy organ of equilibrium can travel sick, it is assumed that about 5 to 10 percent of the population here have a particularly high sensitivity - for example, women are affected more frequently than men, especially at the beginning of Menstruation or in pregnancy. Even in people who are afraid of flying or who from the outset have a nausea, for example. Traveling sickness actually occurs relatively often when driving, and migraine patients are very vulnerable.

Prevention possible with simple means
But even if the motion sickness is widespread - in the vast majority of cases disappear the symptoms such as nausea or dizziness on its own again, as soon as the person is no longer exposed to unfamiliar movements or when used on sea voyages usually after about two days of habituation. Nevertheless, there are various ways to prevent the motion sickness non-drug: So it is generally recommended to always sit in the direction of travel, drink alcohol before the trip, to avoid strong head movements and if possible, even take the wheel - because the Travel sickness affects mostly only front passenger. In addition, it is advisable when driving in cars or buses, to look straight ahead on the road, to pay attention to a controlled and regular breathing and reading and to look out of the side windows to avoid. On cruises, it is often helpful to fix the horizon or the coast firmly with the eyes and to stay in large vehicles in the middle of the ship and book a cabin with window. Traveling sickness can also be counteracted on the plane: it is often recommended to choose a seat near the wings. (No)

Picture: Gerd Altmann