Speaker: Tobias Moser
Universitätsmedizin, Georg-August-Universität Göttingen
Title: Biophysics of hearing: from synaptic sound coding to optogenetic restoration
The sense of hearing is truly fascinating from a biophysical point of view. For example, neural mechanisms enable the processing of information in the ear and early auditory pathway at rates of hundreds per second over hours with submillisecond temporal precision. Downstream of sophisticated micromechanics and sensory transduction, inner hair cells of the ear need to pass on all information via their ribbon synapses. Here, each synapse drives a single auditory neuron to fire at high rates. Interestingly, the presynaptic active zones within a given hair cell vary in their Ca2+ signaling. This likely enables the inner hair cell to decompose auditory information into functionally distinct neuronal channels to the brain for wide dynamic range coding. So far, no causal treatment is available for such sensorineural hearing impairment. Therefore, we explore the use of optogenetics to stimulate the auditory nerve for future cochlear implants with improved frequency and intensity resolution of coding. Towards this end proof of principle for optogenetic restoration has been obtained in rodents.