A research team at the University Medical Center Gottingen has created a cochlear implant that uses light to restore auditory responses in deaf gerbils. The study provides a proof-of-concept that combining optical stimulation with genetic manipulation can successfully restore sound perception, and could lead to a new generation of more accurate cochlear implants.
Approximately 360 million people worldwide have hearing impairment. Traditional cochlear implants can partially restore the ability to hear in many of these patients by stimulating ear cells with electrical signals. In such devices, however, the generated current tends to spread around each point of contact, activation of a large population of neurons and limiting the resolution and clarity of sound signals.
Christian Wrobel and colleagues tackled this obstacle by designing a light-based cochlear implant. Optical stimulation promises spatially confined activation of neurons in the auditory nerve, potentially yielding spatially precise ear cell stimulation with limited spreading.