Optimization of a Non-invasive Electrophysiological Method for Studying the Functionality of Auditory Nerve Fibers

Acoustic overexposure can induced temporary or hearing loss. Usually hearing loss is associated with cochlear cell damages. Recently, a new pathological entity was described and called "hidden hearing loss". In animal model, the histopathology revealed a selective reduction in the number of auditory fibers, resulting in a decrease in the amplitude of wave I of the auditory brainstem response. Electrocochleography (Ecog) is a method for recording the electrical potentials of the cochlea (e.g. wave I). In clinical routine, Ecog is performed invasively with sedation or local anesthesia. Actually, a non invasive approach could be perform but it seems necessary to optimize this method and to define reference values in healthy volunteers.

Inclusion Criteria: * Between 18 and 55 years old * be affiliated to a social security system * understand (oral and written) of the French language * be a qualified hearing with normal tympanogram and audiogram Exclusion Criteria: * have a complaint of hearing * have a exposure to noise (professional and/or activities) * refusal to participate in the study * have ear infections and/or ENT medical history * have cardiovascular, metabolic, neurological and psychiatric desease * being a protected person * healthy volunteer who has received compensation equal to or greader than 4500€ in clinical study