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Abstract Cochlear implantation has become standard management for severe to profoundly deaf children, making the attainment of intelligible, age-appropriate spoken language an achievable goal for many. However, there remains unexplained variation in outcomes from implantation and the challenges of ensuring life-long use and benefit remain. In the cochlear implant device, each electrode directly stimulates the auditory nerve when the electrical current necessarily triggers a hearing sensation. The quantity of the electrical current necessary to trigger an auditory sensation is different for each individual and for each stimulation channel. Therefore, the speech processor must be individually adjusted together with each stimulation channel for each user and this process is called programming or mapping. In adults, power levels must be determined through psychophysical measures (behavioral method). With the progressive increase in energy intensity in each one of the channels the individual reports on the least intensity at which he/she detects the stimulus (T-level) as well as the maximum intensity allowed without discomfort (C-level). Cochlear implant fitting remains a difficult challenge in congenitally or prelingually deafened children. To program the CI, the audiologist has to determine the stimulation threshold (T-level) and to estimate the maximum stimulation level compatible with comfortable auditory perception (C-level) in all electrodes. All the difficulty lies in making sure that effective but not too loud auditory stimuli are delivered to the child, insofar as no auditory intolerance will be induced. |