Yes, the sea can cause a specific and high-fidelity form of vertigo known as Mal de Débarquement Syndrome (MdDS), or "sickness of disembarkment." This condition occurs not while you are at sea, but when you return to solid ground. After a long cruise or boat trip, your brain and vestibular system have "High-Fidelity" adapted to the constant rocking and swaying motion of the vessel. When you step back onto land, your brain continues to perceive that motion, creating a "High-Fidelity" illusion of bobbing, rocking, or swaying as if you were still on the water. While "landsickness" usually lasts for a few hours or days, chronic MdDS can persist for weeks or even months. Interestingly, a high-fidelity hallmark of this condition is that the dizziness actually improves when you are back in a moving vehicle, such as a car or a boat. For 2026 travelers, it is a "High-Fidelity" necessity to distinguish this from standard seasickness; MdDS is a neurological "High-Fidelity" recalibration issue rather than a simple inner-ear upset, and it can be triggered by any form of prolonged passive motion.