If you set foot onto a boat or a cruise ship in rough waters, you'll want to bring your sea legs. This term originally only referred to the process of getting used to the constant pitching and rocking on the high seas. It's broadened over the years, and now getting your sea legs can also mean getting used to any new situation.
The movement of a boat on water can easily lead to motion sickness, or in this case, seasickness. This is a condition in which your inner ear and eyes, the parts of your body that detect motion, send conflicting messages to the brain. The system in your body that keeps you from falling over when you're walking down the street is called the vestibular system. Your eyes and a section of your inner ear called the semicircular canal are the main players here. Inside the canal are tiny hair cells that detect the movement of fluid. It's this movement that's sent as a message to the brain by way of some auditory nerves. Lean over to the left, the fluid sloshes in that direction and your brain understands that you're leaning to the left, even if your eyes are closed. Motion sickness throws a wrench in this process. If you see one thing with your eyes and your inner ear senses another, your brain won't understand which signal to process.
Let's say you're in a windowless cabin of a small cruise ship and you're being tossed to and fro. Your eyes tell the brain "I'm just sitting still here on the bed" while your inner ear screams "will somebody please steady this ship!" Your semicircular canal feels the motion of the boat without being able to see the horizon moving up and down. Sometimes seeing the horizon is enough to get seasickness in check. For others, it could mean using any or all of the following:
- Homeopathic remedies
- Acupressure bracelet
- Habituation therapy
- Homespun tricks
Seasickness means nausea, dizziness, vomiting, fatigue and headaches. The good news is that once you're back on land, the condition eventually goes away. It usually doesn't happen immediately though -- most people experience brief lingering effects. These effects can last a few hours or a day or two. In these cases there's really nothing to worry about. But what if your seasickness persisted for weeks, months or even years? And what if the only thing that made you feel better was being in motion? It turns out there's such a condition. It's called Mal de Debarquement syndrome.