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bioRxiv · 10.1101/2023.10.04.560827

Wireless electrocochleography in awake chinchillas: a model to study multimodal modulations at the peripheral level

Perez-Valenzuela, C.·Vicencio-Jimenez, S.·Memmel, M.·Delano, P. H.·Elgueda, D.
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Abstract

The discovery and development of electrocochleography (ECochG) in animal models has been fundamental for its implementation in clinical audiology and neurotology. In our laboratory, the use of round-window ECochG recordings in chinchillas has allowed a better understanding of auditory efferent functioning. In previous works, we gave evidence of the corticofugal modulation of auditory-nerve and cochlear responses during visual attention and working memory. However, whether these cognitive top-down mechanisms to the most peripheral structures of the auditory pathway are also active during audiovisual crossmodal stimulation is unknown. Here, we introduce a new technique, wireless ECochG to record compound-action potentials of the auditory nerve (CAP), cochlear microphonics (CM), and round-window noise (RWN) in awake chinchillas during a paradigm of crossmodal (visual and auditory) stimulation. A total of four chinchillas were successfully recorded during the experimental protocol. There were non-significant differences in CAP, CM, and RWN amplitudes in response to auditory stimulation alone (clicks and tones) as compared to audio-visual crossmodal stimulation. These results suggest that cognition, such as attention or working memory, is needed for the corticofugal modulation of auditory-nerve and cochlear responses. In addition, we introduce the use of wireless ECochG in animal models as a useful tool for translational research.

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Perez-Valenzuela, C., Vicencio-Jimenez, S., Memmel, M., Delano, P. H., Elgueda, D.. 2023-10-06. Wireless electrocochleography in awake chinchillas: a model to study multimodal modulations at the peripheral level. https://doi.org/10.1101/2023.10.04.560827

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