Trouble balancing? A new spinning chair may provide answers

The University of Alabama's new invention, the first of its kind in the world, will help in the study of dizziness and inner ear structures.
Written by Melanie D.G. Kaplan, Inactive on

If anyone understands the problems of the inner ear, it’s University of Alabama professor Dr. Craig Formby, who has logged more than 25 years in the field. For the last decade, he has been working on an invention he unveiled in late 2009: the Roto-Tilt Chair, which can tilt, twirl, rotate and flip test subjects (no, thanks!) so researchers can gather data on how the inner ear contributes to balance—and why the system sometimes goes wrong.

The custom-designed chair was built to Formby’s specifications by Neuro Kinetics Inc. of Pittsburgh. Funding came from the National Institutes of Health and UA. I recently talked to Formby, the university’s director of research faculty development, who was not sitting (or spinning) in the chair during our conversation. (Scroll down to see it in action.)

Where did this idea come from?

It grew out of my career, seeing how vestibular testing was historically done. For the most part, it tests the horizontal semicircular canal, to the exclusion of the other structures in the inner ear. Our goal was to test each of the parts on both sides and to be able to isolate the structures. We hope that will allow us to learn what’s wrong with the inner ear in parts that are dysfunctional or diseased. It opens up some opportunity for us for treatments.

What are some of the areas you’ll be studying?

We were particularly interested for senior citizens, who are prone to falls. Falls are the leading cause of fatal and nonfatal injuries among seniors, and about half of the fall injuries of those over 65 are believed to have a vestibular component to it. But historically, we could only come up with a definitive diagnosis in about half of the cases So a chair like this could be very valuable in being able to diagnose, treat and rehabilitate. That was a large motivation for the chair.

It is anything like what Navy pilots and astronauts use to train for high G-forces?

Not directly. They have more centrifugal devices. Our device is much more clinical and limited to testing the five components—the three semicircular canals (which sense head tilts foreword, backward and on a horizontal plane), and the two otolith structures in each ear (the saccule, which is responsive to up/down, elevator-type accelerations; and the utricle, which is responsive to front/back accelerations like those in a moving car).
But the Navy has contacted us about using it for some of their studies. We’ve also visited NASCAR headquarters to discuss potential applications of the chair for improving safety of the driver.

So your chair spins every which way.

Basic spinning around is easy. My chair will do that, plus, you can take a person and tilt them back so the head’s in a supine position, legs out straight and spin them in a BBQ spit position. We have a full range of almost 360 degrees. We can even spin you like you’re in an upside down office chair. It will use all three planes of motion—yaw, roll and pitch, to use pilot’s terms.

Are you using spin dummies or real people right now?

We’ll do a lot of testing on dummies early on. We have two dummies—one that’s a head and torso and one that’s a full-fledged 150-pound emergency service dummy. We have a NASCAR-type harness, but it’s not particularly comfortable when you’re in some of the more provocative positions, so we want to make sure it’s secure and comfortable. It’s a steep learning curve because no one has anything like it.

Is it hard to get people to volunteer to sit in the chair?
Surprisingly there are a lot of people who want to ride in our chair. Or maybe not surprisingly. I won’t say it’s an amusement ride, but it’s similar to those motions, just in a very controlled way. We went through a process with our investigative review board here for all the safety measures.

This post was originally published on Smartplanet.com

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