This work consisted in studying perceptual and the underlying neuronal mechanisms involved during voice perception in postlingually deaf cochlear-implanted patients and normal-hearing controls stimulated through cochlear implant simulation. We have analyzed behavioral performance of implanted patients during a voice detection task and other protocols perception tasks of paralinguistic information, such as gender. Two groups of patients were tested using either a longitudinal follow-up or a transversal approach. We compared their performances to those of control normal-hearing subjects tested in cochlear implant simulation (vocoder). In addition, we have performed in normal-hearing subjects, a fMRI study, to reveal the effect of a cochlear implant simulation in the cortical activity of areas sensitive to human voice. Results agree to point out, following cochlear implantation, a deficit in voice perception, unlike speech comprehension. This deficit is not only due to the degradation of the signal by the vocoder, but probably results from cortical reorganization induced by deafness.
