Contribution of a contralateral hearing aid to perception of consonant voicing, intonation, and emotional state in adult cochlear implantees

Binaural hearing in cochlear implant (CI) users can be achieved either by bilateral implantation or bimodally with a contralateral hearing aid (HA). Binaural-bimodal hearing has the advantage of complementing the high-frequency electric information from the CI by low-frequency acoustic information from the HA. We examined the contribution of a contralateral HA in 25 adult implantees to their perception of fundamental frequency-cued speech characteristics (initial consonant voicing, intonation, and emotions). Testing with CI alone, HA alone, and bimodal hearing showed that all three characteristics were best perceived under the bimodal condition. Significant differences were recorded between bimodal and HA conditions in the initial voicing test, between bimodal and CI conditions in the intonation test, and between both bimodal and CI conditions and between bimodal and HA conditions in the emotion-in-speech test. These findings confirmed that such binaural-bimodal hearing enhances perception of these speech characteristics and suggest that implantees with residual hearing in the contralateral ear may benefit from a HA in that ear.