Using unorthodox methods, a U of M professor is questioning everything we know about motion sickness.
Made of crude materials, the small chamber consists of three large textured walls, one with a map of the United States fixed to it. During his studies, Prof. Thomas Stoffregen, director of the U’s Affordance Perception-Action Laboratory, invites visitors to step onto a sensor inside the chamber. Suddenly, one of the walls zooms forward, forcing the test subject off balance.
Here, in this humble lab in the landlocked Midwest, Stoffregen has come up with a theory he hopes will turn what we know about motion sickness on its ear.
Scientists have long believed that the source of motion sickness lies inside the body — the inner ear, known as the organ of balance.
Stoffregen suggests otherwise.
He contends that when we enter a challenging environment — be it a boat, a roller coaster or the back seat of a car — it’s poor posture control that causes us to get sick.
Our bodies are constantly swaying, whether we’re conscious of it or not, he said. It’s when we sway too much and lose our balance that motion sickness sets in.
“The way that you sway is predictive of whether you’re susceptible to motion sickness,” Stoffregen said.
This approach to understanding motion sickness — affecting at least a third of the population — has won some support from fellow researchers, but it’s taken some time to gain acceptance.
“His theory is original. It’s innovative,” said Robert C. Kennedy, an adjunct psychology professor at the University of Central Florida. “It’s a different way of looking at motion sickness.”
Michael Waak, 24, says he’s “notorious” among his friends for getting queasy. A graduate student at the University of Minnesota, he says his stomach often turns when he walks up flights of stairs or when he’s on an elevator. He carries Dramamine in his backpack at all times. When he rides in a car, he makes sure to eat something beforehand, and he prefers to drive.
“It’s difficult,” he said. “People get impatient with me or think I’m making it up as some kind of excuse to avoid certain situations or activities.”
Waak said he’s convinced that his queasiness is tied to his inner ear. When he went to Europe for a month, he wore a motion sickness patch behind his ear that released medicine to numb the feeling of motion.
One of the reasons so many people buy into the traditional theories on motion sickness is because those ideas seem very intuitive, Stoffregen said. He doesn’t dispute the fact that people boarding a ship, for example, will experience changes in their inner ear.
“But that doesn’t mean those are the only things that can cause what’s going on there,” he said. Being on a ship forces people to control their body differently, he said. “You have to get your sea legs.”
The same is true for experiments conducted in his moving room, which has been around more than a decade.
Unlike the first moving room built in Scotland in 1972, which had walls that were moved by hand, the U’s version is mounted on wheels that travel back and forth on rails, which are controlled by a computer. The computer can be programmed to vary how far and how fast the walls move, allowing researchers to create unpredictable movement patterns, similar to, say, a ship bobbing in the waves.
In the chamber, people are tested for up to 40 minutes, while data about their “body sway” are collected. The results consistently show that body posture and movement strongly predict whether a person is prone to motion sickness, Stoffregen said. “If I look at your sway, I can make a better estimate of your susceptibility than you can,” he said.