Authors: Roman Stracke1,2, Daniel Kipping1,3, Franklin Alvarez1,3, Yixuan Zhang1,3, Waldo Nogueira1,2,3,4
1Hearing and Neuro Technology Group, Dept. of Microelectronics, Universitat Autònoma de Barcelona, 2Auditory Prostethic Group, Dept. of Otorhinolaryngology, Hannover Medical School, 3Cluster of Excellence “Hearing4All”, 4Catalan Institution for Research and Advanced Studies
Background: Electrocochleography (ECochG) refers to the recording of electrical potentials from the cochlea and auditory nerve, which enables valuable insights into the auditory periphery. We propose a modeling framework for estimating intracochlear ECochG recordings from hair cells and nerve fibers in response to acoustic and electric stimulation.
Method: The framework is constructed by integrating several existing phenomenological and biophysical models of key subsystems of the auditory periphery to individually estimate hair cell and nerve fiber contributions. We conducted two experiments for acoustic-only and electric-acoustic stimulation respectively, in which estimated responses and experimental data were compared in terms of waveform morphology, amplitude growth functions, and electric-acoustic interaction.
Results: Modeled responses for acoustic-only stimulation yielded waveforms and amplitude growth functions in good agreement with experimental data. Modeled waveforms show typical components as cochlear mirophonics, auditory nerve neurophonics, summating potentials, and N1 onset peaks. Electric-acoustic stimulation yielded electric masking, but with lower attenuation when compared to the experiment.
Conclusion: The results suggest a more in-depth examination of the phase relationships of individual ECochG components, particularly the outer hair cells. Further, this work provides a framework for ECochG responses from hair cells and nerve fibers in the context of electric-acoustic stimulation, facilitates the interpretation of ECochG responses, and adds to the discourse of underlying mechanisms in electric-acoustic interaction.
