From left: Professor of mechanical engineering Dr. John Williams, professor of neuroscience Dr. Leslie Stone-Roy and graduate student J.J. Moritz are developing a device to hear with the tongue. (Photograph: Colorado State University)

Jan 16, 2015 | News Americas

FORT COLLINS, Colo., USA: An estimated 36 million people in the U.S. alone suffer from hearing loss. Although surgically implanted hearing aid devices have been used effectively for many years, not all patients are eligible for this procedure. Researchers have now developed a new technology that could help deaf patients hear through a retainer in their mouth.

The new technology, which was developed at Colorado State University, relies on a Bluetooth-enabled earpiece that detects sounds and sends electrical impulses to an electrode-packed retainer. By pressing their tongue against the retainer, users feel a distinct pattern of electric impulses as a tingling or vibrating sensation.

The tongue contains thousands of nerves and the brain is able to decode complicated information from tongue sensations, according to the researchers. Therefore, the patient's brain will learn to interpret specific patterns as words through training, thus allowing him or her to "hear" through his or her mouth, they explained. 

After filing a provisional patent for the technology, the scientists launched a study that aims to determine which parts of the tongue detect electrical impulses and whether those areas differ from person to person. In the study, participants place an array of electrodes in their mouth and report where they feel electrical impulses and how strong they are. If nerve patterns are found to be consistent, the mouthpiece could be standardized for all patients; it not, it will have to be customized for every patient, which is likely to affect cost. 

The researchers believe that their invention could become a less invasive and cost-effective alternative to cochlear implants in the future. Today cochlear implants are considered the most successful medical prostheses worldwide to restore a sense of sound to deaf or hearing-impaired patients. However, not every patient is a candidate for the expensive surgical procedure, which has inherent risk and can cause additional damage to sensory cells in the inner ear. According to manufacturer Cochlear, over 40,000 adults and 30,000 children in the U.S. have received cochlear implants since they were approved by the Food and Drug Administration in 2000. The researchers at Colorado State University estimate that a cochlear patient pays at least $100,000 for prescreening, implants, surgery and follow-up therapy