Hearing thanks to light stimulation

People who are hard of hearing as they grow older can be helped by a conventional hearing aid. However, in the case of severe hearing loss or complete deafness, the environment remains mute even with the best device. Cochlear implants, hearing prostheses for the inner ear, provide a remedy: acoustic impulses picked up by a microphone are converted into electrical impulses. These stimulate the electrodes implanted in the cochlea, from which the auditory nerve then receives its impulses. However, the artificially generated signals only provide the affected person with a reduced hearing experience. Dr. Patrick Ruther, a physicist at the University of Freiburg, and his team at the Department of Microsystems Engineering would like to use a new type of cochlear implant to increase natural hearing for those affected. In collaboration with colleagues at the University Medical Center Göttingen, they are replacing the electrodes of the conventional electrical implant with a series of micro-LEDs. Instead of electrical stimulation, the hearing ability is produced with light stimulation on genetically modified cells in the cochlea. Before the implant can be tested on humans, however, it must pass long-term testing.