Auditory localization in realistic environments by normal-hearing and hearing-impaired listeners
Jörg M. Buchholz, Virginia Best, Gitte Keidser · The Journal of the Acoustical Society of America · 2012
The ability to correctly localize sounds is important for general awareness of the auditory scene and communication in adverse acoustic conditions. However, most localization studies are performed in rather simple and artificial conditions. In particular, very few studies have considered localization in reverberant environments or in the presence of complex interferers, and no studies have systematically investigated the effect of distance. In the present study, localization performance was therefore measured as a function of source-receiver distance using a virtual auditory environment. With increasing source-receiver distance the direct-to-reverberation energy ratio decreases and the auditory system increasingly relies on mechanisms related to the precedence effect. Both aspects may be particularly problematic for hearing-impaired listeners. The acoustics of a cafeteria was simulated with the room acoustic software ODEON for a large number of source-receiver locations. Signals were generated for a 3D array of 41 loudspeakers using the loudspeaker-based room auralization (LoRA) toolbox. Localization performance was measured in normal-hearing and hearing-impaired listeners with a bilateral hearing loss in the simulated cafeteria with and without a multi-talker speech background. The experimental results were correlated with a number of acoustic measures derived from dummy head recordings of the different acoustic conditions.