Some people experience nausea and even vomiting when riding in an airplane, automobile, or amusement park ride. One study, published in PloS one in 2013, suggested that 3-D movies can also cause nausea.
This condition is generally called motion sickness. When riding on a boat or ship, it is commonly referred to as sea sickness – but it is the same disorder.
Motion is sensed by the brain through different pathways of the nervous system including the inner ear, the eyes, and the tissues of the body surface.
When the body is moved intentionally, for example when walking, the input from all of the pathways are coordinated by our brain.
The symptoms of motion sickness appear when the central nervous system receives conflicting messages from the sensory systems: the inner ear, eyes, skin pressure receptors, and the muscle and joint sensory receptors.
As an example, if someone is sat on a boat or in a car (not looking out of a window), their inner ears sense movement up and down, left and right, but their eyes see a static view, as if they are not moving at all. It is hypothesized that the conflict among the inputs is responsible for motion sickness.
