Electrical Impulse Parameters and Neuronal Population in the Cochlear Implanted Patient-PULSE (PULSE)

PULSE - Paramètres de l'Impulsion électrique et Population Neuronale Chez le Patient implanté cochléaire - Etude en Ouvert, Non contrôlé, Non randomisée

The cochlear implant provides good auditory performance despite high inter-individual variability, but performance in noise remains limited. Modification of the coding strategies could improve these performances. A better characterization of the remaining neuronal population by looking for the charge integration efficiency (which depends on the duration and the amplitude of the electrical pulse) would allow an optimization of the settings by adapting either the duration or the amplitude of the pulse according to the quality of the remaining neuronal population.

The cochlear implant provides good auditory performance despite high inter-individual variability, but performance in noise remains limited. Modification of the coding strategies could improve these performances. Currently, the intensity perceived by the patient is coded by the duration and the amplitude of the electrical impulse but companies have different approaches and fix one of the two parameters for the setting of the processors. A better characterization of the remaining neuronal population by looking for the charge integration efficiency (which depends on the duration and the amplitude of the electrical pulse) would allow an optimization of the settings by adapting either the duration or the amplitude of the pulse according to the quality of the remaining neuronal population.

Post-lingually cochlear implant users with 12 months of auditory experience Modifications of pulse parameters to determine the charge integration efficiency which is related with neuron survival population

The pulse amplitude and/or the pulse phase duration will be optimize to improve the intensity resolution of the cochlear implant which may benefit speech perception

Charge integration efficiency will be determined for each electrode by noting the minimum and maximum loudness perceived by the patient as function of pulse phase duration and amplitude

3 electrodes that span the range of charge integration efficiency values will be selected as test electrodes. Three intensities will be presented to the patient through the implant and it will be asked to the patient to determine which intensity is higher than the others.

Inclusion Criteria: post-lingually deaf adults with at least one year of cochlear implant experience unilateral and bilateral cochlear implant recipients Oticon device with Neuro Zti array Patient affiliated to french social security Consent signed Exclusion Criteria: Patients under court protection, guardianship or curatorship