Tongue piercings are now more than just an accessory for parents and teenagers to fight over. Engineers at the Georgia Institute of Technology have created a bionic wheelchair controlled by a tongue piercing that outperformed and was preferred over the standard guidance system for people with severe paralysis.

The Tongue Drive System is navigated by a magnetic stud placed on a person’s tongue. A special headset worn by the user tracks the motion of stud, allowing the tongue to serve as joystick for the wheelchair. Alternatively, the system could be linked to a computer’s mouse, so they could surf the web or type a letter.

"It's really easy to understand what the Tongue Drive System can do and what it is good for," said principal investigator Dr. Maysam Ghovanloo, an associate professor in the School of Electrical and Computer Engineering at Georgia Tech, whose findings were published in Science Translational Medicine. "Now, we have solid proof that people with disabilities can potentially benefit from it."

Nearly one in 50 people carries some form paralysis in the upper or lower extremities, with the most common causes being stroke, spinal cord injury, and multiple sclerosis. The Tongue Drive System is an assistive technology geared toward helping those with tetraplegia, where body control below the neck is partially or totally impaired in all four limbs.

In this study, 23 able-bodied and 11 tetraplegic participants were asked to test the Tongue Drive System along with the sip-and-puff wheelchair, which is the standard assistive tool for tetraplegia. With sip-and-puff, users draw and push air through a straw mounted on their wheelchair to execute four basic commands that drive the chair.

Even though most of the tetraplegic subject had years of experience with sip-and-puff, they were able to maneuver a wheelchair three times faster with tongue-guided system and with the same accuracay, according to the study's finding.

"Tongue piercing put to medical use — who would have thought it? It is needed and it works!" continued Dr. Anne Laumann, professor of dermatology at Northwestern University Feinberg School of Medicine in Chicago. Dr. Laumann came up with the idea of a piercing, after problems with an earlier model that used a glued-on tongue magnet. This magnet would fall off after a few hours, which presented a possible choking hazard.

Scientists from the Shepherd Center in Atlanta and the Rehabilitation Institute of Chicago also contributed to the project.

"By the end of the trials, everybody preferred the Tongue Drive System over their current assistive technology," said co-author Joy Bruce, manager of Shepherd Center's Spinal Cord Injury Lab. "It allows them to engage their environment in a way that is otherwise not possible for them."

Jason Disanto, who was paralyzed from the neck down after a diving accident in 2009, was one study participant who believes the Tongue Drive System could be transformative for his life.

"The Tongue Drive System will greatly increase my quality of life when I can start using it everywhere I go," Disanto said. "With the sip-and-puff system, there is always a straw in front of my face. With the Tongue Drive, people can see you, not just your adaptive equipment."

More trials with larger pools of subjects are needed before the system can be sold commercially, but Dr. Ghovanloo’s startup company, Bionic Sciences, is working toward that goal.

"All of my projects are related to helping people with disabilities using the latest and greatest technologies," Dr. Ghovanloo said. "That's my goal in my professional life."

 

Source: Kim J, Park H, Bruce J, et al. The Tongue Enables Computer and Wheelchair Control for People with Spinal Cord Injury. Science Translational Medicine. 2013.