Flat spinning rides affect me to now end. Ugh. Now, the way a sailor on a ship prevents sickness is relatively easy. I was in the Navy, so I do know this. First off, staying in your cabin, or a restroom is the worst thing for you, because your inner ear is shifting fluids around for balance, but your eyes see no change in the scenery i.e.your bed, or bathroom floor (toilet). The best thing is to go up topside where you can focus on the horizon. Two good things happen here. One, you can vomit over the side, and there is no smell to deal with or mess. Two, you slowly come back to normal. It can be a long process, but it does work. The reason most coasters don't affect most people is for that very reason. Usually coasters affect those people that shut their eyes on the ride, or have just eaten too much food, and yes...there certainly can be somewhat of a placebo effect.
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