Auditory fatigue: a new challenge in prevention

Aromatic solvents can provoke deafness. The diagnostic of occupational deafness is carried out by pure-tone audiometry, a technique which is capable of testing the perception of auditory messages at the central level. But this technique could not detect peripheral traumatisms hidden by central mechanisms. A up-regulation of the cochlear inputs at the level of the dorsal cochlear nucleus and a down-regulation at the level of the inferior colliculi are the main actions of the central plasticity. Today, other tools can assess cochlear dysfunction without any efferent loop effects. Otoemissions are objective measurements coming from the cochlea only and they can be associated with a contralateral stimulation triggering the stapedial and the olivocochlear reflexes. Such measurements could complete data obtained with the pure-tone audiometry to assess early cochlear sufferings. Moreover, these measurements will allow the plasticity mechanisms to be avoided.