Assessment of individual head-related transfer function and undirected head movements of normal listeners in a moving speech-in-noise task using virtual acoustics
* Presenting author
Spatial release from masking (SRM) is the improvement in speech intelligibility of the target when a distractor noise is spatially separated. Two factors improve accuracy in sound localization during testing: (a) listener head movement and (b) use of individual head-related transfer functions (HRTFs). Little is yet known about their roles in SRM tasks when conducted in the acoustic virtual environment (VAE). In the present study, individual HRTF and undirected head movements are assessed in a SRM task. A speech-in-noise test is performed with normal-hearing adults using binaural reproduction. Listeners are asked to identify target digit-triplets always positioned in front at 0°azimuth, under the presence of a stationary or moving distractor noise. The SRM is calculated, by subtracting the speech reception threshold (SRT) measured when the target and distractor are spatially separated from the SRT measured for collocated target-distractor. The distractor is in several spatial configurations: (1) stationary at 0° azimuth, (2) stationary at 90°, and (3) moving away to the target from 0°to 90°. The three spatial configurations are assessed in four test conditions from 2 binaural reproduction methods (dynamic vs. static; with or without free head movement) X 2 HRFT sets (individually measured vs. dummy-head HRTFs).