Adaptation of cochlear implant fitting to various telecommunication systems: a proposal for a 'telephone map'

Despite the innovations in cochlear implant (CI) technology in recent years, some auditory tasks remain difficult for CI recipients. This work proposes the creation of specific maps for telephone communication (via conventional phone and via Internet protocol, VoIP). In light of our preliminary results, we believe that our experimental maps might improve conventional telephone and Internet communications for CI recipients.

This study aimed to: (1) analyze the spectro-temporal characteristics of the signals; (2) evaluate speech recognition scores using two different types of telephone communication; and (3) change some map parameters on the basis of the previous signal analysis, to obtain a specific map for telephone use.

Eleven Cochlear™ Nucleus® CI recipients were tested for bisyllabic word recognition in quiet using reproduced voice and transmitted voice via conventional telephone and Skype® using the habitual-ACE (SLB) map, and two experimental maps (F- and V-Map).

The results showed a worsening of word recognition scores with SLB-Map via telephone (30.5%) and VoIP (18.6%) compared with those achieved with the same map in an anechoic booth. In the experimental listening conditions, 65% and 54% of patients performed better with F- and V-Map, respectively, up to a maximum of performance improvement by 35% via telephone and 25% via VoIP.