While we naturally think that we hear with our ears, it is really the brain that converts sound waves into what we perceive as sound. Our most distinctive organ also has a lot of plasticity, being able to adapt its regions to perform tasks normally not assigned to them. Blind people, for example, often have the part of the brain responsible for vision working to more precisely interpret audio and create a better mental picture of what’s around. This principle is what led researchers at Colorado State University to attempt to use the tongue as a medium for passing sound to the brain in deaf people.
The researchers developed a flat shaped neurostimulator with a bunch of electrodes in a grid at one end. It’s connected wirelessly via Bluetooth to an earpiece that captures sound. The system processes the audio signals received by the earpiece and converts them into electrical pulses that are delivered through the stimulator. The user simply presses his tongue against the electrodes on the mouthpiece and feels tingling or vibration. The idea is that this sensation, really sound interpreted another way, can be translated by the brain into perceived audio if given proper training.
There’s much work to be done to prove the technology and make it practical. Currently, the researchers are mapping out the tongue’s nerves and studying how volunteers respond to the electrical stimulation. They’re trying to figure out whether the device will work uniformly for all people or whether it will need to be individually customized. The researchers hope that this technology will become a new option competing with cochlear implants and that it may help overcome hearing loss for a wide variety of people.