Jablonski L, Harczos T, Wolf B, Hoch G, Dieter A, Hessler R, Ayub S, Ruther P, Moser T
In case of deafness, cochlear implants bypass dysfunctional or lost hair cells by direct electrical stimulation (eCIs) of the auditory nerve. However, spectral selectivity of eCI sound coding is low as the wide current spread from each electrode activates large sets of neurons that align to a place-frequency (tonotopic) map in the cochlea. As light can be better confined in space, optical cochlear implants (oCIs) promise to overcome this shortcoming of eCIs. This requires fine-grained, fast, and power-efficient real-time sound analysis and control of multiple microscale emitters. Here, we describe the development, characterisation, and application for hearing restoration of a preclinical low-weight and wireless LED-based multichannel oCI system and its companion eCI system. The head-worn oCI system enabled deaf rats to perform a locomotion task in response to acoustic stimulation proofing of concept of multichannel optogenetic hearing restoration in rodents.