Motion sickness is a condition where the inner ear is disturbed by externally produced motion such as traveling in a ship or a car or the motion of an airplane in turbulent atmosphere. The labyrinth, which in layman terms is the inner ear is affected and hence affects our sense of physical balance and positional equilibrium. This in turn, creates a condition of spatial disorientation.
What causes motion sickness?
Our brain senses motion through three routes:
Three signals from the ear i.e. gravitation, motion and acceleration. The eyes i.e. vision. Proprioceptors i.e. the deeper tissues of the body. When we move ourselves, the input feedback to our brain is coordinated. When the movement is not in our control, the feedback may clash as a result. For example, when we drive a car, our bodies are still but sudden jerks and motions are taken to be wrong inputs and hence, motion sickness.
Experts have brought forward the thesis that such difference in perception by the three senses is possible for the disorientation.
Try imagining that while playing a racing game on your play station, your eyes sense movement, mostly at high speeds but your inner ear tells your brain that you eye’s input is wrong and hence, the clash. Some people may suffer motion sickness and throw up even when they are not in motion such as in this case.
Motion sickness, although common has been a mystery to medical practitioners regarding its causes. The above is only a hypothesis that still has not been proved.
It has been seen that when the motion-sensing organs of the inner ear are absent, motion sickness does not appear in any case. This roughly shows that the inner ear is critical to causing motion sickness.
Even blind people suffer motion sickness, which means eyes don’t have much to do with motion sensing. Generally, it is seen that complex movements have a larger probability of inducing motion sickness. Most of them involve motion in both coordinate plains i.e. simultaneous motion in two directions.
The input clash within the brain seems to involve our neurotransmitters i.e. substances that transmit signals from spinal cord nerves to the brain.
What are the symptoms of motion sickness?
Symptoms of motion sickness are:
Nausea
Vomiting
Vertigo (Dizziness)
The symptoms are not limited to these and there are a variety of other conditions that are reported by patients.
Is there a difference between motion sickness and sea sickness?
Motion sickness and sea sickness although appear different, but are actually same fundamentally. Sea sickness is the same as after riding an airplane, or after a ride at the roller coasters at the amusement park. Many of the people may suffer something similar in a ship and this is referred to as sea sickness.
