PITTSBURGH — The human tongue is an extraordinary bit of flesh. It's alternately squishy and tense, at times delicate and others powerful. It helps us taste, talk and tie cherry stems, all the while avoiding two interlocking rows of sharpened enamel that know only how to gnash. Now, it seems the tongue may even serve as a gateway to the human brain, providing us with the opportunity to treat serious afflictions from multiple sclerosis to combat-induced brain injuries.
The tongue is a natural candidate for electrical stimulation, thanks in part to a high density of sensory receptors and the concentration of electrolytes found in saliva. This has allowed researchers at the Tactile Communication and Neurorehabilitation Laboratory at the University of Wisconsin-Madison to develop a pattern of electrodes that can be placed on the tongue and attached to a control box. All together, the system is called a Portable Neuromodulation Stimulator (PoNS).
Once hooked in, patients undergo 20-30 minutes of stimulation therapy, or CN-NiNM (cranial nerve non-invasive neuromodulation), matched to a regimen of physical, occupational and cognitive exercises specific to the ailment being treated. Each exercise corresponds with different patterns of tongue stimulation, which in turn coax the brain to form new neural pathways. These pathways remain active even after the stimulation has been removed, meaning the therapy can have lasting effects.
After treatment with CN-NiNM, patients with multiple sclerosis have been shown to have a 50 percent improvement in postural balance, 55 percent improvement in walking ability, a 30 percent reduction in fatigue and 48 percent reduction in M.S. impact scores (a measure of physical and psychological impact of M.S. from the patient's perspective). Extraordinary numbers by any standard, but if you really want to understand the project's impact, read about Kim Kozelichki ditching her hobbled limp for a healthy jog on the University of Nebraska's Medical Center blog.
Best of all, researchers have reason to believe CN-NiNM can not only slow functional loss, but also restore previously lost functions. It's this promise that has the U.S. Army Medical Research and Materiel Command (USAMRMC) interested. In collaboration with the University of Wisconsin at Milwaukee and NeuroHabilitation Corporation, the Army hopes to harness this emerging technology to "restore lost physical and mental function" for both service members and civilians suffering from traumatic brain injury, stroke Parkinson's and multiple sclerosis.