Zonas mortas na cóclea: considerações teóricas

Abstract

When the auditive via is working normally, it largely enables the human being to have the use of different everyday life situation in which it is necessary a good oral communication. If an individual has hearing loss, the limitations generated in his/her life will depend on the type and degree of this loss. In cases of sensorineural hearing loss, there are generally difficulty in relation to speech identification. The lesion location (outer or inner hair cells the cochlea) will influence the individual auditive responses. Regions where inner hair cells or adjacent neurons do not work are named dead regions in the cochlea. Therefore, the information generated by the basilar membrane vibration in this region is not transmitted to the central nervous system. However, a tone with sufficient high intensity can be noticed in functional regions near this zone. This causes information excess in the same region. The dead regions in the cochlea presence or not brings implications to the adaptation of hearing aids and, consequently, to the individual performance mainly in relation to speech identification. It is the greatest objective of patients who look for auditive rehabilitation. The objective of this work is to show what literature mentions about cochlear working, sensorineural hearing loss, sound amplification in this cases; and finally, to discuss more specifically about dead region in the cochlea, diagnostic strategies and implications of dead region in the cochlea presence or not in the process of selection and adaptation of hearing aids.