Binaural advantages in users of bimodal and bilateral cochlear implant devices

Abstract

This paper investigates to what extent users of bilateral and bimodal fittings should expect to benefit from all three different binaural advantages found to be present in normal-hearing listeners. Head-shadow and binaural squelch are advantages occurring under spatially separated speech and noise, while summation emerges when speech and noise coincide in space. For 14 bilateral or bimodal listeners, speech reception thresholds in the presence of four-talker babble were measured in sound-field under various speech and noise configurations. Statistical analysis revealed significant advantages of head-shadow and summation for both bilateral and bimodal listeners. Squelch was significant only for bimodal listeners.

Figures

Figure 1

Mean values of HS, SQ, and SU effects measured in seven bilateral (CI + CI) and seven bimodal (CI + HA) users. Error bars indicate standard errors of the mean.