Researchers funded by the National Institute of Biomedical Imaging and Bioengineering have demonstrated that their novel Tongue Drive System is superior to other assistive devices used by individuals with tetraplegia.
In a small clinical trial, the researchers showed for the first time that individuals with tetraplegia can maneuver a wheelchair three times faster using the Tongue Drive System and with the same accuracy as the currently used sip-and-puff system. The speed and accuracy of the Tongue Drive System was even more impressive given that the study participants had years of daily experience using the sip-and-puff technology, which requires inhaling and exhaling through a straw attached to a pneumatic switch that maneuvers the wheelchair.
The new technology offers a significant measure of increased independence for those reliant on assistive technologies to perform daily life tasks. The work was performed by a team led by Maysam Ghovanloo, Ph.D., Georgia Institute of Technology, and was published in the November 27 issue of Science Translational Medicine.
The Tongue Drive System takes advantage of the fact that virtually all paralyzed individuals remain able to move their tongue. The researchers have seized upon this phenomenon to turn the tongue of individuals with tetraplegia into a highly sensitive and accurate joystick. The system employs a magnetic tongue stud worn by the user to wirelessly relay the position of the tongue to the computerized wheelchair. The complete system allows an individual to use his tongue to steer the wheelchair much like a radio-controlled toy car is guided using a joystick.
Participants also tested the use of the Tongue Drive to operate a computer. Able-bodied individuals and individuals with tetraplegia tested moving a computer cursor to click on random targets on the screen, as well as navigating a maze with the cursor. Eleven individuals with tetraplegia compared the Tongue Drive System to the sip-and-puff system and 23 able-bodied individuals compared the Tongue Drive to the computer mouse and keypad. Both groups adapted to use of the Tongue Drive with just 30 minutes of training and improved rapidly with additional experience.
At the end of the trials the participants reported that, compared to their current assistive technology, they preferred the Tongue Drive System, which allows a more seamless, less cumbersome interaction with their environment. Unlike other assistive technologies that are mounted on the wheelchair or on a computer, they also liked the fact that the Tongue Drive System is worn on the body and remains usable even when they are transferred to bed or another wheelchair.
Grace Peng, Ph.D. Program Director at NIBIB adds “We have been thrilled to support and watch this revolutionary rehabilitation work of Dr. Ghovanloo’s team unfold. It is particularly rewarding that this work was supported by an American Recovery and Reinvestment Act (ARRA) NIH Challenge Grant. ARRA grants were special two-year grants to design innovative solutions to our most challenging biomedical research problems. This work is a significant step towards vastly improving the independence and quality of life of individuals with tetraplegia, and is a true ARRA Challenge Grant success story.”
Currently, testing of the Tongue Drive System has been confined to the lab or hospital. The research team is planning tests outside of the laboratory to see how patients function with the Tongue Drive System in their homes, workplaces, and a variety of other environments.
 The tongue enables computer and wheelchair control for people with spinal cord injury. Kim J, Park H, Bruce J, Sutton E, Rowles D, Pucci D, Holbrook J, Minocha J, Nardone B, West D, Laumann A, Roth E, Jones M, Veledar E, Ghovanloo M. Sci Transl Med. 2013 Nov 27;5(213) [Link]