Abstract:

The Completely-In-The-Canal (CIC) hearing aid, due to its placement in the ear canal, has acoustic advantages that are not offered by traditional amplification. Among these advantages are increased high-frequency gain, reduction of the occlusion effect, and subjective reports of improved localization ability over other types of aids. Quantitative data are readily available to verify the frequency response and occlusion effect; however, data on localization ability have been primarily anecdotal. A series of experiments has been designed to document the effect of CIC hearing aid use on auditory localization performance. A normal-hearing subject group, fit with low-gain CICs, was used in this phase; later studies will utilize hearing-impaired listeners and a variety of devices. The use of normal hearing subjects allowed an assessment of localization ability independent of the effects of hearing loss. Localization accuracy was measured using the God's eye localization pointing (GELP) technique [Gilkey et al., Behav. Res. Methods, Instrum. Comput. 27(1), 1--11 (1995)]. Results showed that subjects wearing the CICs were able to localize over the entire spatial presentation range of the stimulus ((plus or minus)180(degrees) azimuth, -74(degrees) to +90(degrees) elevation). Localization accuracy data will be presented.