A little-known fact: the tongue is directly connected to the brain stem. This anatomical feature is now being harnessed by scientists to improve rehabilitation.
A team at the University of Wisconsin–Madison recently found that electrically stimulating the tongue can help patients with multiple sclerosis (MS) improve their gait. MS is an incurable disease in which the insulation around the nerves becomes damaged, disrupting the communication between body and brain. One symptom is loss of muscle control.
In a study published in the Journal of Neuro-Engineering and Rehabilitation, Wisconsin neuroscientist Yuri Danilov and his team applied painless electrical impulses to the tip of the tongue of MS patients during physical therapy. Over a 14-week trial, patients who got tongue stimulation improved twice as much on variables such as balance and fluidity as did a control group who did the same regimen without stimulation.
The tongue has extensive motor and sensory integration with the brain, Danilov explains. The nerves on the tip of the tongue are directly connected to the brain stem, a crucial hub that directs basic bodily processes. Previous research showed that sending electrical pulses through the tongue activated the neural network for balance; such activation may shore up the circuitry weakened by MS.
The team is also using tongue stimulation to treat patients with vision loss, stroke damage and Parkinson's. “We have probably discovered a new way for the neurorehabilitation of many neurological disorders,” Danilov says.