From a long-awaited cruise, to just an afternoon on the water, nothing can put a crimp in your plans more effectively than a bout of seasickness. Seasickness, or more correctly motion sickness, has its root cause in your inner ear. When sitting in a boat and looking at your friends, watching TV or whatever, your eyes tell your brain that you are not moving. However, your sense of balance, which is located in your inner ear, is telling your brain a different story. These crossed signals start you down the road to seasickness.