Bimodal neglect: When electrically- and acoustically stimulated ears do not play nice with each other

This study describes speech perception in quiet, before and after implantation, in 54 adult cochlear implant (CI) patients with usable hearing in the ear contralateral to the CI. Patients had preoperative aided CNC word scores of at least 8% as well as stable unaided hearing in the unimplanted ear throughout the analysis period. Word identification scores in quiet were analyzed for the implanted ear only (CI), acoustic hearing ear only (HA), and the bimodal condition (CI + HA) to determine changes in performance over time and to characterize bimodal benefit (difference between bimodal score and best single-ear score). On average, patients experienced 6% bimodal benefit in quiet after implantation. Not surprisingly, speech scores in the implanted ear and in the binaural condition significantly improved post-implantation. However, scores in the HA decreased unexpectedly after implantation in almost one third of the patients despite unchanged PTA. Although simple explanations like hearing aid malfunction or ...