The fine evaluation of the function of auditory neurons in silence and in noise in humans is difficult, if not impossible, to date with the conventional methods available. That is why in certain situations, the hearing aids of patient with hearing loss fail, especially in the presence of noise.
In this study the investigators aim at investigating the global spontaneous and sound evoked human auditory nerve activity from electrophysiological acquisitions performed directly on the cochlear nerve in patients requiring posterior fossa surgery.