Perception of Intonation by Bimodal and Bilateral Cochlear Implant Users

Bilateral hearing which is a fundamental characteristic of normal auditory system provides significant advantages in adverse listening conditions. In cochlear implant users, binaural hearing can be achieved via bilateral cochlear implant (CI/CI) or binaural-bimodal stimulation, i.e. a cochlear implant in one ear and a hearing aid in the other (CI/HA). It is assumed that CI/CI hearing and CI/HA hearing differ with respect to their physiological sources and functional benefit. Although both hearing prosthesis (CI/CI or CI/HA) lack several of the features needed to allow listeners to experience the full binaural advantage conferred by a normal-hearing auditory system it can, however, provide significant advantages over the use of a unilateral hearing prosthesis. Most of the accepted assessment clinical materials are not sensitive enough to evaluate the contribution of binaural hearing rehabilitation via CI/CI or CI/HA hearing for the perception of intonation. In a previous study the perception of intonation was evaluated in 29 adults CI/HA users via a closed-set format design with the same target talker. The results of the study showed small bimodal benefit. The test paradigm was apparently an easy task for the adult listeners and not sensitive enough to show the expected CI/HA bimodal benefit over cochlear implant alone.

The perception of correct intonation identification will be computed for each listener in each of the listening conditions. The amount of change in the fundamental frequency that was required in order to identify a question will be computed for each listener in each of the conditions. ANOVA with repeated measures will be used to assess the differences among the conditions for each group as well as the differences among the groups.