Device Uses Flashes of Light to Restore Hearing

The optogenetic cochlear implant translates sound into optical stimulation patterns via LEDs placed within the cochlea.
Image: University Medical Center Göttingen

Scientists in Germany have succeeded in restoring hearing sensations in gerbils using flashes of light. The technique, if it can be developed for humans, could offer a more refined, high-resolution auditory experience than what can be achieved with current hearing devices such as the cochlear implant.

The scientists, led by Tobias Moser, a professor of auditory neuroscience at University Medical Center Göttingen, achieved the effect using optogenetics. The technique involves genetically altering specific neurons so that they respond to light, and has become one of biotech’s hottest tools.

In this case, the researchers altered auditory neurons, and then controlled them with light delivered with implanted optical fibers. They described their experiments today in the journal Science Translational Medicine.

Moser and his colleagues are attempting to solve a problem that has stumped engineers for decades. The cochlear implant, invented half a century ago, does a decent job of sensing and converting speech in an otherwise quiet space. But move that conversation into a crowded room, and the wearer hears a jumbled mess.