title: Optogenetic stimulation of the auditory pathway.
abstract: Auditory prostheses can partially restore speech comprehension when hearing fails. Sound coding with current prostheses is based on electrical stimulation of auditory neurons and has limited frequency resolution due to broad current spread within the cochlea. In contrast, optical stimulation can be spatially confined, which may improve frequency resolution. Here, we used animal models to characterize optogenetic stimulation, which is the optical stimulation of neurons genetically engineered to express the light-gated ion channel channelrhodopsin-2 (ChR2). Optogenetic stimulation of spiral ganglion neurons (SGNs) activated the auditory pathway, as demonstrated by recordings of single neuron and neuronal population responses. Furthermore, optogenetic stimulation of SGNs restored auditory activity in deaf mice. Approximation of the spatial spread of cochlear excitation by recording local field potentials (LFPs) in the inferior colliculus in response to suprathreshold optical, acoustic, and electrical stimuli indicated that optogenetic stimulation achieves better frequency resolution than monopolar electrical stimulation. Virus-mediated expression of a ChR2 variant with greater light sensitivity in SGNs reduced the amount of light required for responses and allowed neuronal spiking following stimulation up to 60 Hz. Our study demonstrates a strategy for optogenetic stimulation of the auditory pathway in rodents and lays the groundwork for future applications of cochlear optogenetics in auditory research and prosthetics.
authors: Victor H
authors: VH
authors: Hernandez
authors: Anna
authors: A
authors: Gehrt
authors: Kirsten
authors: K
authors: Reuter
authors: Zhizi
authors: Z
authors: Jing
authors: Marcus
authors: M
authors: Jeschke
authors: Alejandro
authors: A
authors: Mendoza Schulz
authors: Gerhard
authors: G
authors: Hoch
authors: Matthias
authors: M
authors: Bartels
authors: Gerhard
authors: G
authors: Vogt
authors: Carolyn W
authors: CW
authors: Garnham
authors: Hiromu
authors: H
authors: Yawo
authors: Yugo
authors: Y
authors: Fukazawa
authors: George J
authors: GJ
authors: Augustine
authors: Ernst
authors: E
authors: Bamberg
authors: Sebastian
authors: S
authors: Kügler
authors: Tim
authors: T
authors: Salditt
authors: Livia
authors: L
authors: de Hoz
authors: Nicola
authors: N
authors: Strenzke
authors: Tobias
authors: T
authors: Moser
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D000075402:Channelrhodopsins; D003051:Cochlea / Q000503:physiopathology / Q000601:surgery; D019929:Cochlear Implantation; D003638:Deafness / Q000601:surgery*; D004558:Electric Stimulation; D005072:Evoked Potentials, Auditory; D008027:Light; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D062308:Optogenetics; D010775:Photic Stimulation; D051381:Rats; D055647:Rats, Transgenic; D017208:Rats, Wistar; D013136:Spiral Ganglion / Q000473:pathology / Q000503:physiopathology
chemical_list: D000075402:Channelrhodopsins