Bimodal Cochlear Implant Processing based on Assisted Hearing algorithms with CCi-MOBILE: an open-source research platform

While speech understanding for cochlear implant (CI) and Hearing aid (HA) users in quiet is relatively effective, listeners experience difficulty in identification of speakers and sound location. Previous studies have reported improved localization and better speech perception when the unilateral CI is coupled with a HA in the contralateral ear. This is referred to as bimodal presentation of speech or electric and acoustic stimulation (EAS). Various CI research interfaces developed by either academic or industry sponsored research teams support proposed signal processing and psychoacoustic investigations but have limited ability to efficiently validate bimodal algorithms. Platforms that support bimodal testing (CI and HA) are either not portable or only provide limited features due to proprietary parameters/routines. CCi-MOBILE, an open-source, portable signal processing research device, developed by UT-Dallas, enables electric and acoustic stimulations simultaneously, thus providing researchers the opportunity to explore new technology and scientific paradigms for the hearing impaired. In the present work, we provide verification and implementation of synchronized bimodal (electric-acoustic) output in an authenticated and efficient manner to support sound and acoustic localization algorithms for experimental investigations.