ELEPHANT

INTERVENTION: Two interventions will be implemented during the study. 1. During the intensive CI‐rehabilitation phase, mapping of the electrical input will be based on an individualized natural frequency alignment as estimated with imaging methods. This natural fitting will be compared to the standard frequency alignment. A daily randomization scheme will be applied whereby the subject acts as his own control, followed by a period of free choice between both maps. Outcome measures will be assessed at several single points, to address the difference between both CI maps, as well as over time, to address the learning curve with both CI maps. 2. In a second stage, after a stable outcome with CI is reached and if a contralateral hearing aid is used, the fitting of the acoustic hearing aid will be optimised and compared to the standard fitting. Outcome measures will be assessed acutely and at the end of a take‐home period. CONDITION: Deafness, Cochlear implant, Tonotopy ; ; PRIMARY OUTCOME: To evaluate the effect of natural place‐pitched electric mapping, the following outcome measures will be compared between the new fitting strategy under investigation (Test) and the standard clinical fitting (Control):; ; ‐ Objective primary outcome: degree of speech understanding (words in quiet, sentences in quiet, sentences in noise) with CI during the first 6 months of rehabilitation.; ; ‐ Subjective primary outcome: patient preference in daily life for either the natural fitting or clinical fitting during the first 6 months of rehabilitation.; ; with CI SECONDARY OUTCOME: Secondary outcomes include objective and subjective measures to reflect biological response, performance, preference and sound quality: ; ; ‐ Telemetric data on the function of the implant and the response of the auditory nerve. ; ; ‐ Speech understanding with the contralateral HA (acoustic input) and bimodally (CI+HA) ; ; ‐ Extended dimensions of sound perception (spatial masking, listening effort, sound quality, spectral resolution, loudness scaling). ; ; ‐ Quality of life in relation to hearing ability. INCLUSION CRITERIA: • Adult (18y or older) and meeting the conventional Dutch CI criteria; • Proficient speaker of Dutch language; • Post‐lingual onset of profound deafness (> 4 years of age); • Subject receives an Advanced Bionics implant with Midscala electrode and an Advanced Bionics sound processor; • Prepared to use a study specific hearing aid (Phonak) for the duration of the study; • Rehabilitation at MUMC+ for the first year after surgery regarding CI as well as HA; • Active participation in trial related procedures such as daily randomization and regular testing.