Evaluation of the Global Auditory Nerve Activity for Exploration of Hearing in Humans

To date, all the electrophysiological methods for auditory testing rely on the measure on synchronous evoked auditory nerve activity. This measure only takes into account the response of the first action potential in every auditory fibber, but provides no information about the neural response during a sustained activity. This can explain why in experimental models, a loss of more of 80% of auditory nerve fibbers cannot be detected by usual electrophysiological measurements. In this study we aim at investigating the global spontaneous and sound evoked auditory nerve activity by recording directly the electrical field by an electrode placed directly on the auditory nerve of subjects during a skull base surgical procedure. We expected to demonstrated differences in the electrical activity between subjects with or without hearing loss.