Motion Sickness

motion sickness, waves of nausea and vomiting experienced by some people, resulting from the sudden changes in movement of a vehicle. The ailment is also known as seasickness, car sickness, train sickness, airsickness, and swing sickness. The principal cause of the disturbance is the effect of motion on the semicircular canals of the inner ear, although other factors such as inadequate ventilation and fumes or noxious odors may contribute. Drugs are available that, when taken beforehand, prevent the occurrence of motion sickness.

---

motion sickness

Sickness caused by contradiction between external data from the eyes and internal cues from the balance centre in the inner ear. For example, in seasickness the inner ear senses the ship's motion, but the eyes see the still cabin. This stimulates stress hormones and accelerates stomach muscle contraction, leading to dizziness, pallor, cold sweat, and nausea and vomiting. Minimizing changes of speed and direction may help, as may reclining, not turning the head, closing the eyes, or focusing on distant objects. Drugs can prevent or relieve motion sickness but may have side effects. Pressing an acupuncture point on the wrist helps some people.

---

motion sickness [′mō·shən ‚sik·nəs]

(medicine)

A complex of symptoms, including nausea, vertigo, and vomiting, occurring as the result of random multidirectional accelerations of a vehicle.

---

Motion Sickness 

a syndrome occurring in man and some animals as a result of rocking on the sea (seasickness), air turbulence and aerobatics (airsickness), or rapid driving over a winding, bumpy road. It is caused by prolonged stimulation of the vestibular apparatus of the inner ear and by the action of impulses that originate in the internal organs on the autonomic nervous system.

The symptoms of motion sickness include fatigue, dizziness, headache, copious salivation, nausea, vomiting (which causes temporary relief), and the appearance of cold perspiration. Prolonged motion may cause loss of consciousness. Aeron and diphenhydramine are used to prevent and treat motion sickness; persons with a highly sensitive vestibular apparatus may take the drugs before embarking on an airplane or ship. Vestibular training (special exercises that increase the stability of the vestibular apparatus) is also helpful in preventing the syndrome.

REFERENCE

Vozhzhova, A. I., and R. A. Okunev. Ukachivanie i bor’ba s nim. Leningrad, 1964.