disembarkment syndrome, MdD, MdDS, Sickness of disembarkment
Also known as Disembarkment Syndrome, Mal de Débarquement Syndrome (MdDS) is a rare disorder of perceived movement that most often develops following an ocean cruise or other type of water travel. MdDS has also been reported to follow air, train, and automobile travel, and less commonly after sleeping on a waterbed, and frequent use of high speed elevators. Symptoms usually begin shortly after the cessation of the motion stimulus and are often increased when in an enclosed space or when attempting to be motionless (sitting, lying down, or standing in a stationary position). The motion sensation may seem to disappear when in passive motion such as in a moving car, airplane, or train.
While MdDS most commonly presents itself after travel, for some there is no known motion event; the onset appears to be spontaneous. MdDS may persist for months to years.
Common symptoms include a persistent sensation of motion such as rocking, swaying, tumbling, and/or bobbing. This sensation of motion is often associated with anxiety, fatigue, difficulty maintaining balance, unsteadiness, and difficulty concentrating (impaired cognitive function). Relief from symptoms may be realized when riding in the car or participating in other motion experience. This can be important feature in the diagnosis of MdDS.
source: MdDS Foundation