Take comfort, summer travelers. Motion sickness is not in your head; it's in your brain, say MIT researchers who study "space sickness" in astronauts.
The good news is that besides popping pills, there are simple steps you can take to alleviate the symptoms as well as make yourself less susceptible over time.
In addition to helping people with car, sea and plane sickness, researchers Laurence R. Young and Charles M. Oman point out that addressing this problem is becoming a priority as space tourism moves closer to reality.
Professor Young, the Apollo Program Professor of Astronautics, is an internationally recognized researcher on the human aspects of space travel and director of the National Space Biomedical Research Institute (NSBRI). Dr. Oman is a senior research engineer in the Department of Aeronautics and Astronautics who leads the NSBRI neurovestibular program and is director of the Man-Vehicle Laboratory (MVL) at MIT. He is an expert on human inner-ear function, the sensory-motor conflict theory for motion sickness, and has written several practical articles on seasickness prevention.
CONFLICTING INFORMATION TO THE BRAIN
The past 25 years of the space program have uncovered more about the physical basis for motion sickness than has ever been known. The MVL does research on the visual and vestibular systems, visual-vestibular interaction, flight simulation, space motion sickness and manual controls and displays. The laboratory's work on how the balance mechanism in the inner ear is linked to space sickness led to models that are used to help humans adapt to space travel and to in-flight simulator motion control.
Professor Young and Dr. Oman, both seasoned offshore sailors, have helped dispel the fallacy that motion sickness is predominantly psychological. Motion sickness, they say, results from conflicting information reaching the brain from your eyes and your inner ear, and from different parts of the inner ear itself.
They point out that motion sickness has affected virtually every astronaut and that virtually everybody with normal inner-ear balance function can be made motion sick.
A TRIP TO MARS
Understanding and remedying motion sickness becomes particularly relevant when planning a manned space flight to Mars.
Scientists have proposed ways of creating artificial gravity during the flight to counter problems with bones, muscles, the cardiovascular system and the manufacture of red blood cells that result from extended time in a zero-gravity environment.
One method, popularized in the movie 2001: A Space Odyssey, involves using a huge centrifuge to create artificial gravity. Professor Young, who was principal investigator in experiments on four space shuttle missions and an alternate NASA payload specialist for the 1993 Space Life Sciences 2 Mission, supports smaller, more practical versions of this rotating environment. But they have the drawback of making users motion sick.
His research addresses ways to minimize discomfort. The good news is that most people seem to get less sick over time as they get used to the unusual movement.
Fighter pilots, for instance, are virtually free of motion sickness when they are in the midst of a training session, but after a break of a few weeks, they are more likely to experience motion sickness as their vestibular balance system returns to normal.
TIPS FOR THE MOTION SICK
��������� Recognize the symptoms of oncoming motion sickness, which range from yawning and drowsiness to increased salivation, cold sweats, headaches and nausea, before they get out of control. The worse motion sickness is allowed to get, the faster symptoms develop.
��������� Take anti-motion sickness medication, such as over-the-counter Dramamine and Bonine or see your doctor for advice on stronger prescription drugs. Be sure to take them at least an hour ahead of time.
��������� If you are on a boat, go on deck to eliminate visual conflict. Being belowdeck will make you feel ill more quickly. Try a method called wave riding, in which you sit upright and let your trunk and neck muscles keep your head and upper body balanced over your hips as the boat moves.
��������� If all else fails, try to wedge yourself into a secure place and go to sleep. Your susceptibility is reduced when you are asleep.
��������� Acupressure wristbands remain controversial. They help some people, although the MIT researchers see such devices as placebos. "Remember that even placebos can help some, if you believe they work," Professor Young says.
��������� If you have had several bad experiences while sailing and are so susceptible that you feel queasy merely at the sight of a boat, it may be that your problem isn't motion sickness but anticipatory nausea. Counter-conditioning yourself by spending time aboard at the dock and going out on calm days may help.
��������� Take heart from the fact that this research indicates that astronauts and regular folks become accustomed to unnatural or nauseating movements over time, with or without medication.
A version of this article appeared in MIT Tech Talk on August 23, 2000.
