En route to sound coding strategy for optical cochlear implants


Khurana L, Harczos T, Moser T, Jablonski L




iScience (2023).


In 2019, disabling hearing loss affected 430 million people worldwide and will reach over 700 million by 2050. Severe-to-complete sensorineural hearing loss is often treated by electrical cochlear implants (eCIs) bypassing dysfunctional or lost hair cells by direct stimulation of the auditory nerve. The wide current spread from each intracochlear electrode array contact activates large sets of tonotopically organised neurons limiting spectral selectivity of sound coding. Despite many efforts, an increase in the number of independent eCI stimulation channels seems impossible to achieve. Light, which can be better confined in space than electrical current, may help optical cochlear implants (oCIs) to overcome eCI shortcomings. In this review, we present the current state of the optogenetic sound encoding. We highlight that optical sound coding strategy development capitalising on the optical stimulation that requires fine-grained, fast, and power-efficient real-time sound processing controlling dozens of microscale optical emitters. is an emerging research area.