Hearing restoration by a low-weight power-efficient multichannel optogenetic cochlear implant system

Abstract

In case of deafness, electrical cochlear implants (eCIs) bypass dysfunctional or lost hair cells by direct stimulation 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 along the tonotopic axis. As light can be better confined in space, optical cochlear implants (oCIs) promise to overcome this shortcoming of eCIs. This requires appropriate sound processing and control of multiple microscale emitters. Here, we describe the development, characterisation, and application of a preclinical low-weight and wireless LED-based multichannel oCI system for hearing restoration and its companion to its sister eCI system. The head-worn oCI system enabled deafened rats to perform a locomotion task in response to acoustic stimulation proving the concept of multichannel optogenetic hearing restoration in rodents.